[HN Gopher] How to build homes with virtually no heating (2020)
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How to build homes with virtually no heating (2020)
Author : whereistimbo
Score : 331 points
Date : 2022-01-18 05:38 UTC (17 hours ago)
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| beAbU wrote:
| Location and climate are very big factors when it comes to home
| insulation.
|
| The South African Highveld for example has an extremely mild
| climate.
|
| My house has no insulation in the ceilings, single pane windows,
| double brick walls with no insulation and air vents all over the
| place to the outside.
|
| The house was built in the 70s I think, using construction
| methods appropriate for that time. So ot very modern.
|
| I have no climate control in my house. And I don't need any. At
| the moment I'm considering some ceiling insulation, because in
| the middle of summer things can get toasty in the evening when
| the hot roof radiates back into the cool house.
| mattlondon wrote:
| I wonder how these "no heating"/"no cooling" homes work in
| situations like mine: my wife is permanently freezing cold,
| sitting around inside with multiple layers on, sometimes a
| blanket, and the heating on full-blast while I am walking around
| in shorts and t-shirt sweating?
|
| I.e. people have different ideas about what a comfortable
| temperature is. In my wife's example it seems like unless she can
| actually "feel the heat" as it were, she is not comfortable.
| dx034 wrote:
| From experience I can say that it works. Simply by using
| different clothes (as you described, t-shirt vs multiple
| layers). The only people who really struggle with no heating
| homes are those who need colder temperatures to sleep. I had
| several guests who complained that they'd like it cooler at
| night than during the day. However, that's not really possible
| if the house isn't really heated anyway and thus won't lose
| heat during the night.
| jsiaajdsdaa wrote:
| Sounds like one of you might have a health condition. She could
| be underweight or anemic, you could be overweight or etc.
| mellavora wrote:
| Maybe not a health condition, might just be the body's set
| point.
|
| There are three biological states: body is cold and needs to
| warm itself, body temp is right (no effort required), body is
| hot and needs to cool itself.
|
| I was born in hot southern climate, my wife in a cold norther
| climate. For me, "body is cold" is rather unnatural and
| uncomfortable. For my wife, "body is hot" is the same. Her
| internal furnace is always on, my internal cooling system is
| always on.
|
| She is happiest at 18C ambient, I am happiest at 22C.
|
| If you want a biological mechanism to explain this, it's
| called epigenetics, and the key factor would be the
| environment your mother was in while you were in the womb and
| she was forming your body.
| darkwater wrote:
| I'm not 100% sure of this. Totally anecdotal but... I was
| born and raised in a continental climate, where during
| winters most day you would stay between -2C and 1C and
| sometimes you can get -10C during nights. I remember
| feeling cold but it wasn't that extreme.
|
| Then in my twenties I moved to a warmer, near the sea place
| where a cold winter is when you get 2/3 Celsius degrees in
| the coldest night and after a few years of that life, now
| when I go back the place where I was born in winter, I feel
| fucking cold (and I have special winter jackets for that).
| eesmith wrote:
| My anecdote is the other way around. I was born in the
| subtropics, grew up w/o A/C. It never got below freezing.
|
| I moved to a colder climate. The first few years I
| complained that the summers were never hot enough. I
| expected and wanted to walk out of an A/C'ed building
| into a wall of heat and humidity.
|
| Now I'm used the colder weather, and find 15C/60F to be a
| wonderfully comfortable temperature.
|
| And nowadays I find winter is the only season to visit
| where I grew up, if I want to feel comfortable.
|
| I figured it wasn't epigenetics or some such, but rather
| that your body could adapt to it. I remember once when it
| was -23C/-10F for a week then warmed up to -10C/14F. I
| rolled the windows down on the car because I felt so warm
| ... and then I noticed the bank thermometer and was
| surprised.
| guythedudebro wrote:
| I think one of them is a woman.
| fullstop wrote:
| Not OP, but my wife and I are both quite thin and have no
| health issues. She is always colder than I am.
| rsynnott wrote:
| It's fairly normal for different people to prefer different
| temperatures, and to a large extent it's probably a learned
| thing. In particular, the idea of what normal room
| temperature is varies quite widely around the world.
| newaccount74 wrote:
| I'm pretty sure that totally healthy people also prefer
| different temperatures.
|
| And it's common that women prefer it slightly warmer; men do
| have a slightly higher metabolic rate on average even when
| they have the same height/weight, and those extra calories
| that the body uses end up as heat.
| Markoff wrote:
| It's common, but I find it strange considering women have
| overal much more fat, so you would expect the roles will be
| reversed.
| wcoenen wrote:
| It's the opposite for us; I'm the one feeling cold, while my
| wife is comfortable. I started wearing a layer of thermal
| underwear in the cold seasons to compensate.
| bee_rider wrote:
| You must embrace the cold. Any attempt to warm yourself will
| just make your body expect warmth. Never turn on the heat,
| and you'll slowly adapt along with the seasons. Maybe set the
| thermostat to 33F so that the pipes don't freeze...
| wcoenen wrote:
| The human body doesn't "expect" anything, it simply must
| maintain its core temperature. If the temperature of the
| environment goes lower, the body responds by
|
| 1) increasing thermogenesis, i.e. convert chemical energy
| to heat through metabolism
|
| 2) reducing heat loss through the extremities by reducing
| blood flow there. In other words, you get cold feet and
| hands etc.
|
| For people not bothered by cold, presumably it's mostly
| (1). For me, being skinny and not having a big appetite, it
| seems to be mostly (2). I suppose I could get used to
| having cold extremities half the year. But why suffer if I
| can simply put on an extra layer of clothing? I don't see
| the point.
| em-bee wrote:
| but you can change what temperature you are comfortable
| with. i have experienced that myself. coming from an area
| with cold winters and heating, moving to an area without
| heating, i found winters absolutely horrible because
| despite mild temperatures outside, having those same
| temperatures inside was unbearable. until i got used to
| it. more or less.
|
| recently i visited a friend in the north who had heating.
| but he complained that their heating was not good enough,
| and i saw him wearing a jacket inside. i, on the other
| hand, felt very comfortable because his weak heating was
| warmer than my no heating.
|
| likewise in milder climates people start to put on winter
| coats when the temperature drops a few degrees outside,
| while i, used to much colder temperatures am still
| running around in a t-shirt much longer than everyone
| else.
|
| the primary problem with it being cold inside is that you
| are not moving enough. while i am fine to have no heating
| in most of the house, i am heating my office because
| there i am sitting for many hours without moving much.
| dx034 wrote:
| For me, socks did the trick. I never had cold feet but always
| felt colder than colleagues in the office. An additional
| layer of socks made me feel warm enough to agree with the
| others on a thermostat setting. Still amazes me how much of
| an effect this had.
| mdp2021 wrote:
| > _about what a comfortable temperature is ... it seems like
| unless she can actually "feel the heat" as it were, she is not
| comfortable_
|
| You wrote it yourself... Comfort is not with the temperature
| (scalar quantity for C implemented roleplaying1), it is with
| the "warmth", with the effect obtained in the internal
| environment, a quality you feel. This is why heat exchange
| feels ineffective compared to radiators. Sheer temperature is
| only partially indicative even outdoors.
|
| Spend time in a car under the sun, in general, but even when
| paradoxically heated by the sun to a good internal temperature
| in cold winter, and see the reaction of the body.
|
| (1A memory cell with a scalar for "health", one for "strength",
| one for "agility"...)
| pqs wrote:
| To feel warm, radiation is more effective than temperature.
| mdp2021 wrote:
| And it has to be the right radiation (hence the example of
| the (bad) environmental quality of a car under full sun).
| lbriner wrote:
| Sometimes this is down to "micro" draughts rather than the
| temperature. Currently, I am sitting in about 19 degrees C
| inside and that should be plenty warm but in my T-shirt, I can
| feel very low level cold draughts caused by windows, small gaps
| etc. and some people are definitely more sensitive to these.
|
| As others have said though, you can hopefully find a suitable
| temperature that both of you accept and it won't cost as much
| to keep it there.
| newaccount74 wrote:
| You can still control the temperature in a Passivhaus, the
| difference is just that you need much less energy to heat it.
|
| It won't solve the problem that people prefer different
| temperatures, though.
| Mromson wrote:
| It saddens me that construction quality is almost irrelevant when
| building a new building nowadays. The profit difference between a
| well-isolated passive building and one that merely meets the
| minimal standards, is often very small, so why bother building a
| passive building?
|
| My personal interest in passive buildings generally revolve
| around maintenance. Passive houses seem to require far less
| maintenance.
| sb057 wrote:
| >The profit difference between a well-isolated passive building
| and one that merely meets the minimal standards, is often very
| small, so why bother building a passive building?
|
| People making decisions about which contractor to use (both for
| public and private projects) are often mandated to choose the
| absolute cheapest bidder, sometimes with the ability of
| choosing a different one if they file mountains of paperwork
| explaining why.
| pjerem wrote:
| That's what norms are for.
|
| If minimal thermal requirements are written in the law, even
| the cheapest builder must build a highly insulated home. In
| my country, it's mandatory to have well insulated home, to
| prove (with tests) that you respect the norms, and it's also
| mandatory to have renewable heat source (mainly heat pumps).
| Sure, it costs a little more, but with the rise of real
| estate prices, it's still way cheaper to build well insulated
| houses.
|
| The building cost since those new norms increased about maybe
| dozens of thousands euros. It's not even a lot given the
| exceptional thermal comfort you get from your money.
| Cthulhu_ wrote:
| > It saddens me that construction quality is almost irrelevant
| when building a new building nowadays.
|
| Depends on where you live; houses in the Netherlands are built
| to high standards when it comes to things like insulation,
| build quality, electrification, etc.
|
| Are houses in the US still built with 2x4's and drywall? You'd
| think they would move to what we have here in the Netherlands,
| mostly sturdy concrete blocks, insulation layer, and a pretty
| brickwork or brickwork-looking facade.
|
| I mean the amount of clips I see on the youtubes of people
| breaking walls make me cringe. A wall should break you, not the
| other way around, :D
| lotsofpulp wrote:
| > I mean the amount of clips I see on the youtubes of people
| breaking walls make me cringe. A wall should break you, not
| the other way around, :D
|
| Why? I think calculating heat loss, noise levels, wireless
| signals, fire resistance, ecological cost, etc would be
| decent metrics to judge the merits of a wall.
|
| But if you are living in civilization, I do not see why the
| wall withstanding the impact of a body is something I should
| care about. Also, there is almost always an external envelope
| of exterior siding plus plywood sheathing that I have never
| seen penetrated by an individual without tools.
| Mromson wrote:
| Some countries have comparatively high building standards,
| but none (that I'm aware of) come close to a Passive House
| standard.
|
| My gripe isn't as much what the minimum requirement is, and
| more the incentive to never go above it, because property
| prices are generally only going up with little regard to
| building standards.
| vinay427 wrote:
| > Are houses in the US still built with 2x4's and drywall?
| You'd think they would move to what we have here in the
| Netherlands, mostly sturdy concrete blocks
|
| Do you mind explaining why you feel this way? There are
| definitely benefits to reinforced concrete such as durability
| and resistance to certain natural elements, but as far as I
| can tell modern fire-treated wood construction tends to be
| nearly as safe in fires or superior in earthquakes, has
| better insulation, and is more ecological during the
| construction process. Overall, I would prefer reinforced
| concrete, but it's more for the "qualitative advantages" as
| it feels more reassuring to the touch.
|
| Speaking of electrification, one complaint I have of most
| construction in at least continental Europe is the consistent
| dearth of electrical outlets in residential settings. Living
| in Switzerland for years and visiting other countries, it
| seemed like an extension cord across the bedroom or living
| room was nearly always needed due to awkward and very limited
| outlet placement. The fire code in a state like California
| seems to have much stricter mandates to prevent this sort of
| thing.
| pierot wrote:
| > Speaking of electrification, ..
|
| Probably because the housing stock in continental Europe is
| older and therefor much more often retrofitted with modern
| electricity. Newly build houses won't have that problem.
| Although I'm not aware of fire regulations having an effect
| on the number of outlets in a room, in my region (Belgium).
| GuB-42 wrote:
| > the consistent dearth of electrical outlets
|
| In France, it was the case in old houses.
|
| On new constructions, a minimum number of outlets is
| required (3 per bedroom, 5 to 7 in the living room, 4 in
| the kitchen, 1 in every other room). This is in addition to
| dedicated circuits (washing machine, oven, dishwasher,
| heating, lighting...) which may have their own outlets.
| RJ-45 networking is also required (1 per room) but
| unfortunately, it is often designed poorly and barely
| usable except for a phone landline.
|
| These are minimums. And it is typically what you get in
| standard apartment buildings. But you can have more. I have
| about double. A friend of mine has an outlet every 50cm!
| adev_ wrote:
| > I mean the amount of clips I see on the youtubes of people
| breaking walls make me cringe. A wall should break you, not
| the other way around
|
| The external wall un old French house can easily reach
| 55/60cm of pure concrete mixed with stones in cold places.
|
| Trust me, it will break you and specially break your will to
| make any hole in them ^^
| dx034 wrote:
| I doubt the maintenance part. I lived in one and experienced
| more maintenance. You have the heat exchanger as an additional
| moving part which needs cleaning, new filters, etc.
|
| Also, you need a perfect seal between inside and outside. So
| any cables going outside (blinds, air conditioning which you'll
| still want if it's 40C outside, etc) needs to be sealed and is
| thus much harder to replace or repair.
| LunaSea wrote:
| > Passive houses seem to require far less maintenance.
|
| Interesting! Could you explain a bit more on how you came to
| this conclusion?
| Mromson wrote:
| In general, this conclusion comes from the notion that a
| passive house has fewer moving parts and requires less
| attention. A poorly insulated house demands that you take
| more active measures to ensure that it keeps a positive
| temperature (so water pipes don't freeze), this is extra
| pertinent should the power go out. A well-insulated house is
| also likely to have fewer points of failure (water getting
| into cracks and whatnot).
|
| A proper passive house generally only has one maintenance
| point, which is the ventilation / air filtration system, and
| temperature control is easy. You don't have to worry much
| about the insides being too hot or too cold, as it should
| keep whatever temperature you set regardless of the weather
| outside.
|
| With all that said, you should generally take everything I
| said with a grain of doubt, as I'm not an expert, and someone
| could well shoot down all my points in the comments. ;-)
|
| My prime goal with any house I buy is to make sure that I
| have to do as little as possible; never worry about water
| being in the wrong place, and never worry about the power
| bill, or temperature in general.
| LunaSea wrote:
| Ah I see, that makes sense.
|
| I've always found Passive Haus design interesting although
| the (expensive) single point of failure that lies in the
| air pumps scares me a bit.
| Mromson wrote:
| Personally I've addressed that concern with a CO2 alarm
| in every room (which you should have regardless, so I
| don't count that against passive houses). I suspect that
| there exist ventilation fallback solutions that can
| address a power failure scenario, but I've yet to find
| any viable ones.
|
| It should be possible to have a system that generates
| automatic airflow should power fail.
|
| Best ones I've found are solar panels, or geothermal
| power generator (geothermal is generally really amazing
| for everything), but that still leaves mechanical
| failure.
|
| That said, it takes quite a bit of time before
| ventilation failure leads to a dangerous CO2 buildup. And
| the addition of having a single entry point for air means
| that it's easy to filter my air through a HEPA filter,
| ensuring top quality air all year round.
| poseva wrote:
| First of all, if you build a PassivHaus in normal climate
| (not cold) you will be amazed to see that you do not need
| a heat pump, you can just use normal electric boiler for
| hot water and use electric underfloor heating mats for
| heating, or infrared panels mounted on the roof. On the
| other side, air-to-air heat pumps have gotten cheaper by
| the year, you can buy a decent heat pump (NIBE) with
| about 4500-5000 euros.
| Mromson wrote:
| Electric boilers are extremely energy inefficient
| compared with heat pumps. If you built a Passive House,
| not going the extra mile for a heat pump seems silly to
| me. Not to mention that heat pumps can easily protect you
| against heatwaves (should any happen).
| coryrc wrote:
| True Passivhaus needs less than 1000W of heating ever; at
| that point the expense of heat pump is unnecessary for
| something rarely used.
| poseva wrote:
| Exactly what coryrc said in his comment, for a PassivHaus
| you recover very slowly the cost of the heatpump and if
| it brakes once in 10-15 years while it takes to recover
| the investition... you will never recover it.
| lostlogin wrote:
| The houses in the article have a lot of wood and decking.
|
| New Zealand is savage on exposed timber. I have tried multiple
| products from expensive to cheap and have the same result on
| all.
|
| A deck which gets rain and faces north west needs re-coating
| every 6 months to 1 year. The combination of heat, UV and water
| is just savage.
| goldcd wrote:
| Have you looked at modified woods like Accoya? (50 year
| guarantee above ground, 25 in water)
| lostlogin wrote:
| Thanks - I hadn't.
|
| I haven't had any degrade to the stage where it needs
| replacement, I just have to keep maintaining.
|
| I'll look into it further, the product looks impressive.
| alkonaut wrote:
| > Our designs combine generous ventilation with high insulation
| (140mm-thick wall framing combined with R4 wall insulation in the
| North Island - far above the Building Code requirements)
|
| NZ North Island is pretty extreme in its non-extremeness. It's
| near perfect for building homes that don't need excessive heating
| and cooling. From a global perspective, 140mm insulated framing
| is nothing. In any colder climate (such as the nordics) or hotter
| climate (such as the south US or southern Europe) a comfortable
| well-insulated wooden frame home needs at least 300mm insulation.
| That's also the code in e.g. Sweden.
| hourislate wrote:
| I've been touting the benefits of Spray Foam Insulation for
| years. It is actually incredible how much money you can save on
| HVAC every year. Your Heating and Cooling equipment can be halved
| in size and your living space is draft free and incredibly
| comfortable. Mate this with geothermal and your utility bills to
| heat and cool are equivalent to someones Starbucks habit (maybe
| less). If the North American building code was upgraded to a
| decent performance level (spray foam, triple pane windows, etc),
| we could probably get away with not having to build another power
| plant for decades.
| turtlebits wrote:
| Spray foam is very expensive and is not sustainable. Mineral
| wool/rockwool is also fairly popular but pricey as well.
|
| Also, it's not just adding insulation. Air tightness is hard
| problem to address for existing houses.
| hourislate wrote:
| Spray foam pays for itself, so it's basically free in the
| long run. Interesting enough people don't bat an eye when
| someone quotes them 20-30 k for a new Kitchen but if you
| quote someone 20-30 k to insulate their entire house they
| look at you like you killed their mother and sister.
|
| The average home has 2000 ft of linear cracks. Everything
| from poorly sealed doors, windows, and envelope. It's like
| the equivalent of keeping your front and back door open all
| year around. So even after spray foaming there is some
| leakage (blown door test).
|
| Really, Spray foam isn't that expensive, you should be paying
| about $3 -$4 a sq/ft at around a R-21 which is cheaper than
| most tile or carpet installations.
|
| https://huntsmanbuildingsolutions.com/en-US/
|
| If I were building a house I would probably go with ICF forms
| all the way up and Spray Foam the attic and basement floor
| (under the concrete floor). If I were renovating, I would
| Spray Foam and try to make the job large enough to cover the
| contractors minimum charge. Even a couple of rooms can really
| help the utility bills.
| turtlebits wrote:
| Double stud construction with blown in cellulose is much
| cheaper than spray foam, and way better for the
| environment.
|
| Also, if you want close to passive house, you'll need way
| more than R-21. I would say only use spray foam if your
| wall cavity is limited and you need the maximum R value.
| hourislate wrote:
| Double stud construction cheaper? Maybe a while back...
|
| Spray Foam although rated at R-21 preforms much higher
| since it seals. Blown in Cellulose settles, attracts
| dust, rodent nesting, and doesn't seal and isn't a vapor
| barrier or water proof. You get what you pay for I guess.
|
| We have a house in Northern Ontario that is around 4000
| Sq/Ft (entirely spray foamed). The costs to heat and cool
| it are 1/3 compared to the house 2800 sq/ft house in
| Toronto (insulated with Fiber Glass, Attic Cellulose).
|
| The biggest hurdle is folks just don't give a fuck about
| the mechanical part of the house. Dry wall covers it all
| up. What's important is the finish that you see everyday.
| mcot2 wrote:
| I wish more municipalities would mandate tighter homes with good
| ventilation. Recently when searching for a new home it was so
| dishearting to see brand new developments where the homes had
| standard insulation, bad orientation for things like solar and
| passive heating and giant fossil fuel based heating systems
| instead of heat pumps. I decided to instead go the oppostie
| direction and buy a 1960's split level that I am modernizing.
|
| It's been quite a challenge to retrofit, we really need to be
| building to a higher standard for new stock. While renewable
| energy is all the rage this rarely gets a mention.
| jsiaajdsdaa wrote:
| In America the latest building craze seems to be a veneer of
| beauty over bad functional design, and a _strong_ mentality of
| "fuck you pay me" from the seller.
| gambiting wrote:
| What do you mean "latest"? Hasn't it (almost) always been
| like this?
| jsiaajdsdaa wrote:
| Some houses used to be built on nice plots of land with
| non-shoe-box design, but I would argue that paying 1.5M for
| a "new" home depot material house on a postage stamp of
| land that will literally collapse when the particle board
| that supports the drywall gets wet... is not very good
| value for money.
|
| It happens, youtube has the proof of it sadly!
| gambiting wrote:
| >>Some houses used to be built on nice plots of land with
| non-shoe-box design,
|
| Yes, but I feel like even "back then" that was an
| exception rather than the norm. There is a LOT of very
| poorly built houses around, and it's not just the problem
| with modern construction. Modern house prices and
| scarcity has made it worse, sure, but it feels like
| "built to the cheapest possible standard" was always a
| thing.
| theshrike79 wrote:
| Also: It's illegal to build multi-storey housing in large
| parts of America. You know, the kind where you have stores on
| the ground floor and apartments above. Illegal and actively
| NIMBYed against.
|
| A grocery store for a neighbourhood, within walking/biking
| distance? Illegal, against zoning laws.
| uoaei wrote:
| Yep, the flippers and the cash-hungry are riding this high as
| long as they can. It's bred quite a bit of entitlement but
| with the bonus that their poor attitudes are rewarded with
| large sums. This will happen (and has been happening) as long
| as housing is an investment vehicle with profit potential.
| jsiaajdsdaa wrote:
| I can live with flippers and the cash hungry, since they
| mostly just do cosmetic repairs and they take some
| considerable financial risk.
|
| But I absolutely despise big corporate builders who hire
| junkies as laborers and conmen as project managers. They
| will cut every corner, deliver late, charge a gigantic
| premium, and not answer your calls after you've taken
| delivery.
| mdp2021 wrote:
| > _with good ventilation_
|
| Mandate windows?!
|
| > _heat pumps_
|
| That means (if I understand you correctly), fans. That is noise
| pollution - some will not have it, and some will not bear it.
| And (after experience), heat pumps can be inadequate for
| heating: they can raise a temperature, not warm the
| environment.
| dx034 wrote:
| If you ventilate purely via windows, you'll need to always
| pay attention to avoid any mould. With a ventilation system
| hooked up to a heat exchanger, there's basically zero chance
| you'll ever experience mold.
| adev_ wrote:
| > That means (if I understand you correctly), fans.
|
| It does not _always_ means fans.
|
| Geothermal or aquathermal heat pumps are fan-less, very
| silent and performs amazingly in cold climate. I have one
| home.
| mcot2 wrote:
| A heat pump can be air source or geothermal and you can use
| them to create hot water for a hydronic system or forced air
| (ducted or non-ducted). So not all of those will create the
| same noise levels. As they can be virtually any size and now
| work well at very low temps, I don't see how they can be
| inadequate for heating. I'd have to hear of an example.
|
| Up in the Northeast U.S. they are still putting oil fired
| boilers in new homes since gas isn't super common outside of
| larger cities. I'd like to see more new homes have solar,
| heat pumps and possibly even stationary batteries in the
| future. These are going to be essential if we want to get off
| fossil fuels.
| perceptronas wrote:
| Windows>
|
| Heat exchangers can be up to 90% effective at saving heat,
| while window ventilation will be 0%.
|
| Noise pollution>
|
| In my cold climate, whoever goes with heat pumps - they
| usually go with "air-water" systems. Meaning only outside you
| have fans and inside you have your typical floor heating.
| dx034 wrote:
| Much higher than 90%. The one I had in the passive house I
| lived in was specified to 98% at most temperature ranges. I
| guess most of the time the temperature difference isn't
| that large anyway (<20C) so they will lose next to no heat.
| patrickk wrote:
| Modern air or ground source heat pumps tend to be quiet, even
| silent, at least according to some deep dives down the
| Youtube rabbit hole on passive houses. Check out the
| "Moonstone house" on Youtube for example.
|
| https://youtu.be/sSE8PurhfQs
| dx034 wrote:
| My neighbour has a air heat pump for a ~200m2 house with
| good insulation, but not a passive house. It's at the edge
| of his property so I regularly pass it. I'd say you need to
| be less than a meter away to hear it at all, and even then
| it sounds like a fan. There's absolutely no vibration or
| so.
|
| However, the house is new, let's see how it the unit sounds
| in 5-10 years.
| tpxl wrote:
| We have a heat pump from ~2008 about a meter away from
| the outer wall of the house and I don't recall ever
| hearing it from the inside. You'll hear it from a few
| meters on the outside, but it has never been a problem.
| It's able to heat a ~250m2 house in -10degC weather.
|
| That being said, do yourself a favor and do not get a
| heat pump connected to 'the cloud'. Our heat pump can't
| be fully controlled locally (some functionality is web
| only) otherwise I'd put it offline. They unnecessarily
| performed repairs on the heat pump to the tune of 500EUR
| because their servers had issues.
| [deleted]
| elric wrote:
| You're wrong on both counts.
|
| Windows don't make for very good ventilation. They are prone
| to letting in either too much or too little air, which means
| you're either wasting a lot of heat, or are not getting
| enough fresh air. Mechanical ventilation with energy recovery
| is _far_ superior. Windows, of course, are great for letting
| in natural light and for creating a sense of spaciousness
| etc.
|
| Heat pumps don't always need big fans, only air source heat
| pumps do, and even those can be made to be pretty quiet. Not
| much louder than a gas furnace.
|
| They definitely can warm an entire house (in fact, they do so
| on a regular basis in many houses in many parts of the
| world), even in the coldest of climates. Heating a Passivhaus
| requires only a tiny unit (except for hot water, but let's
| ignore that for a minute).
| mdp2021 wrote:
| > _Windows don 't make for very good ventilation_
|
| The point was not with ventilation quality, but with the
| feasibility and compromises of alternatives. (The strict
| point was with defining "mandating good ventilation".)
| Mechanical ventilation with energy recovery may be far
| superior, but if that means constant noise it will be an
| issue - to some, a radical issue.
|
| > _They definitely can warm an entire house_
|
| And I have stated that they can be perfectly inadequate and
| ineffective (explicitly: which is not contradicted by your
| statement). Evidently, it will depend on implementation,
| and again on the expected effect (where temperature is only
| a partial factor).
|
| Speaking of implementation, I have been in hotels where the
| heating pumps were unbearable in that _they made the room
| tremble and clearly vibrate_.
|
| So, when one speaks of mandating technologies, there are
| critical implementational issues to be remembered, and the
| "embrace" drive is to be immediately criticized (just
| applying one's usual duly Reflection). It is relevant that
| I have seen in the past legislation mandating some
| technologies only halfway trough (e.g. mandating valves
| without mandating pressure control systems), creating
| immense damages on large territories.
|
| Edit: also:
|
| > _Heat pumps don 't always need big fans ... Not much
| louder than a gas furnace_
|
| You have not stated they are perfectly silent, 0db - in
| fact, you seem to suggest the opposite. As said, some do
| not tolerate background noise.
|
| I do not see where you read anything wrong.
| empiricus wrote:
| "Mechanical ventilation with energy recovery may be far
| superior, but if that means constant noise it will be an
| issue - to some, a radical issue." I've installed this in
| my house, it is virtually silent. This is for ~200m3 of
| clean air/hour. If I turn it on higher you can hear it a
| little.
| mdp2021 wrote:
| > _virtually silent_
|
| Decibels?
|
| I have seen air purifiers publicized as exemplary silent,
| and people unable to bear the noise of the minimum fan
| speed.
|
| There may also be a matter of the exact sound - maybe
| some are less disturbed by (say) a hum instead of a hiss;
| it probably has to be tried.
| rsynnott wrote:
| While I don't have mechanical heat recovery ventilation,
| I've been in lots of apartments and houses that do (it's
| virtually mandatory for new builds here). You won't know
| it's there unless you're in the room that the device
| lives in, and even then it's not loud.
| jaclaz wrote:
| A well insulated house needs some sort of mechanical
| ventilationm otherwise you will have problems with humidity
| and - in worst cases - mould.
|
| The ventilating units are usually placed in the basement and
| are not noisy (but need some maintenance and cleaning).
|
| There are heat pumps that simply heat water and are suitable
| for underfloor heating, no fans.
|
| Underfloor heating is usually "slower" (compared to air
| heating) but works just fine, actually better.
| londons_explore wrote:
| I think a key issue is that generally the person designing a
| house isn't the same person who will be paying the energy bills
| in 30 years time.
|
| Few people will pay a lot extra for a better insulated house.
|
| The end result is that the cheapest insulation allowed by law is
| used rather than something that costs more today but saves a lot
| in the long run.
|
| I wonder if a solution to this problem might take the form of
| "We'll sell you the house, _and_ promise to pay half the energy
| bill for the next 50 years ". Obviously there are issues with
| that... is there a better way to align incentives?
| alkonaut wrote:
| > I think a key issue is that generally the person designing a
| house isn't the same person who will be paying the energy bills
| in 30 years time.
|
| Those who build homes must typically be planning on staying at
| least a few years in them though, say 10? Insulation is pretty
| cheap compared to running an AC in a poorly insulated home.
| Also it's not just a cost issue, it's more about comfort.
| Sleeping in a cool space without an AC blasting is worth
| something too.
|
| The person designing the building codes though is the person
| responsible for the energy use and supply of the country, it's
| CO2 emissions and so on. So slowly getting more efficient
| building codes seems like it should be universal.
| lbriner wrote:
| I think the assumption is that with regulations, the government
| can force builders and buyers to accept the higher standards
| and the associated higher cost in return for the common-good.
| stakkur wrote:
| You mean like Earthships, a modern idea decades old?
| https://www.earthshipglobal.com/
|
| What I like about Earthships is they attempt a wholistic answer
| to the gnarly nexus of housing access, resource use, and self-
| sufficiency, and do it in a simple, beautiful way.
|
| The ideas and methods already exist; we don't need architect-
| designed glass/steel boxes or exotic manufacturing techniques and
| materials.
| sgt wrote:
| South Africa here, it's not common to build energy efficient
| houses although it's gradually getting slightly better.
|
| I'm busy changing all my windows to double glazed (single glazed
| is the norm, believe it or not) and proper insulation in above
| the ceiling.
|
| Instead of freezing my ass off every winter it's now super
| pleasant, and it's cooler in summer. Such a non-brainer - I just
| don't understand why people don't do this more.
| poseva wrote:
| I've also built a simple and small (99sqm) PassivHaus in Romania,
| 5 years ago. Everybody, and I mean everybody from family to
| friends called me nuts, but I've got my payback this winter when
| the energy prices went trough the roof and I'm just slightly
| affected.
|
| The house is elevated from the ground on 12 concrete columns so
| that I can insulate under the foundation beams using glass foam,
| insulation on walls is 30 cm of EPS graphite, underfloor 45 cm
| EPS and on the roof, 50 cm and the orientation is full on south.
| For heating it consumes about 1500-2000 kWh per year (December,
| January, February and a maybe a small part of March)
|
| What is the big difference between houses built in North America
| and Europe is that the European houses are built using concrete
| and masonry which give them a lot of thermal mass which is
| crucial to this kind of builds.
|
| Have a look here [0], this is the first PassivHaus in my area and
| is nicely documented. The cost of building a PassivHaus in my
| country typically goes about 20-25% more than a traditional one.
|
| [0]: http://www.sdac.ro/site/archives/category/passivehouse
| goodpoint wrote:
| > small (99sqm)
|
| Is that correct? 99 is not small at all.
| poseva wrote:
| Small in comparison with a typical single family homes that
| goes >150 sqm in my area. I completely agree with you, 99 sqm
| is more than enough for a 4 people family.
| em-bee wrote:
| it depends on how you can use the space. 4 people can mean
| three bedrooms. in some parts of asia the average 3-bedroom
| flat is 150m2. a few years ago i did a search in a european
| city and likewise was unable to find 3-bedroom apartments
| with less than 120m2. 4 was 150m2 minimum.
|
| the problem is huge living rooms that can't be divided up
| and repurposed to make living space for more people.
|
| work from home doesn't need a lot of space, but with young
| kids i absolutely need a lockable room. my current office
| room is 5m2. plenty of space. but finding an apartment with
| that kind of room is rare.
| kwhitefoot wrote:
| The average size of homes in the UK is under 80 m2. See
| https://shrinkthatfootprint.com/how-big-is-a-house
| rsynnott wrote:
| > I did a search in a european city and likewise was
| unable to find 3-bedroom apartments with less than 120m2.
| 4 was 150m2 minimum.
|
| You simply chose the wrong European city :) Try Dublin,
| the city of 70sqm 3 bed apartments (in fairness, these
| aren't allowed under current planning regs, but there are
| quite a lot of old ones).
| [deleted]
| jmrm wrote:
| People doesn't give the massive importance the isolation has.
| Some years ago we remodelled our home and added XPS (Extruded
| Polystyrene) to insulate the roof of the house. After that we
| use the AC only three or four days in the year, and before that
| we had to use it at least a complete summer month. That house
| is in the south-interior of Spain, so heat is no joke here.
|
| If somebody are constructing or remodelling any house I
| recommend it to add any insulation they can in any shape, in
| less than five years you'll recover what you spend, and if you
| add PV panels for electricity or a thermosiphonic system to
| heat water, you'll recover the investment in about 10 years,
| with a healthy amount of available health in the devices to
| continue saving money with a proper maintenance.
| fullstop wrote:
| > That house is in the south-interior of Spain, so heat is no
| joke here.
|
| I looked up a few areas (Ciudad Real) to see what you meant
| by heat, but it seems quite similar to a good portion of the
| northern USA. This makes sense, I suppose, given the similar
| latitude.
| SOLAR_FIELDS wrote:
| Insulation is so, so important. I work out of my garage
| currently and Texas winters get reasonably chilly and of
| course summers are hot. I'm lucky enough that my garage is
| actually under a room in my house such that it's insulated
| (as you imply, roof insulation is one of the most important
| places to insulate). Even simply adding padded insulation and
| trim to the exterior door and garage door made it viable
| enough to stay cool in the summer with zero extra cooling and
| warm in the winter with a small infrared heater.
| madaxe_again wrote:
| We've just built a 45m2 log cabin to passive standards here in
| Portugal - heavily insulated in walls, floor, roof, lifted off
| the ground on concrete columns, double glazed, only heat source
| is a 2.5kw log stove. Everyone here (who all live in
| uninsulated concrete houses heated by open fireplaces) said we
| will freeze in the winter, roast in the summer. We situated the
| house on a north facing slope, to minimise sun exposure in the
| summer. Means little direct light in the winter, but we think
| (have yet to experience a summer in it) the balance will be
| good.
|
| As I write this, the stove is out, having burned out overnight,
| it's -11 outside, and 25 inside. We are getting through a
| ridiculously tiny volume of firewood compared to when we were
| living in a more traditional house for here - less than 1/8
| the volume.
|
| Insulation works. It's also cheap. I don't understand why
| people would build new structures without it.
| mschuster91 wrote:
| > Insulation works. It's also cheap. I don't understand why
| people would build new structures without it.
|
| People are a bit sceptical about many insulation forms...
| plastic-based stuff is either a fire hazard (see Grenfell
| Tower) or extremely toxic waste (if it has been treated with
| fire suppressants), asbestos is completely banned for good
| reasons, and rock/glass wool can also spread nasty ultra-fine
| dust.
| madaxe_again wrote:
| We've purely used rockwool. It's enclosed within a
| semipermeable membrane, so no possibility of dust escaping.
| phillc73 wrote:
| It would be very interesting to learn more about this build.
| Was it something pre-fabricated (I've seen "kit" log homes
| advertised) or something completely custom?
| madaxe_again wrote:
| Pre-fab, although loosely so - about 1000 me-hours to make
| it into a functional home. I unfortunately can't recommend
| the outfit I bought it from, as they screwed up and shipped
| only part of the order, sent me defective parts (bad and/or
| incorrectly machined timbers), and had the worst post-sales
| service I've encountered in anything - but there are plenty
| of companies out there that make decent kit cabins.
| kitd wrote:
| It is interesting that you insulate under the house.
|
| One of the more intriguing passive house designs I saw was one
| where the insulation went down 2-3m _into_ the ground all
| around the house footprint. This trapped the natural ground
| heat within that area and fed it upwards into the house. It
| took about 18 months for the ground to warm up, but once it was
| there, the ground /house warmed itself with virtually no input.
|
| This was in the UK. Colder climates may vary ofc.
| alksjdalkj wrote:
| > It is interesting that you insulate under the house.
|
| I think anyone who's gone camping will appreciate the need
| for insulation between the ground and whatever you're trying
| to keep warm - a good sleeping pad is crucial for keeping
| warm.
| aaron695 wrote:
| Gravityloss wrote:
| How would that work? Average temperature in the UK is about
| 15 C. If your house is at 24 C, this would mean you are
| constantly leaking heat into the ground from the bottom...
|
| I guess one can consider the cube of earth an insulator, it's
| got a lousy insulation value per meter but it makes it up in
| thickness.
| arethuza wrote:
| Don't think 15C is correct - looks more like 8.5C to 11C in
| England and 7C to 9C in Scotland.
|
| http://projectbritain.com/weather/average.htm
| Gravityloss wrote:
| Sorry, I was wrong indeed, thanks for the correction
| a_square_peg wrote:
| You can look up ground temperature for your location here
| - https://weatherdownloader.oikolab.com/downloader.
|
| Layer 4 is between 1m to 3m depth beneath the surface.
| arethuza wrote:
| Apologies, I didn't appreciate you meant average
| temperature underground - that is definitely _much_
| warmer. We have a ventilation shaft for an old limestone
| mine near our house and on a cold day the warm air rising
| from it is very noticeable.
| a_square_peg wrote:
| I wasn't the commenter so no worries about apologies...
| just wanted to point out where you can find this
| information. :)
| whirlwin wrote:
| We have an old house from 1988 located in Norway. Walking on
| the non-insulated wooden floor is very unpleasant. We will
| refurbish, and insulate under the floor, but it will not be
| anything near a passive house because of other construction
| shortcomings
| ricardobayes wrote:
| well try non-insulated tiles here in Spain haha. I don't
| know why houses are built to such a low standard in Spain.
| Even the UK had better quality constructions when I was
| there, and that says a lot (single glazed windows, poor
| insulation, weak plumbing)
| joking wrote:
| no harsh climate overall so much less insulation is
| needed?
| ricardobayes wrote:
| Mainland Spain falls into the single digits at night at
| winter so definitely would need insulation, because there
| is also no central heating. People resort to heating with
| their aircons and portable heaters. I'm sad because I
| expected better infrastructure from 45% income tax at the
| highest bracket.
| jakub_g wrote:
| I come from Poland (sub-zero in winter; can be anywhere
| from -20C to +10C but typically 0-5C), but the winter I
| lived on the Spanish eastern coast was the coldest in my
| life: thin walls and windows, stone floor, no heating
| apart from little portable heaters, 5 degrees and rain
| outside.
|
| Now I live in French southern coast, the buildings are
| slightly better but still poor. In my place even with all
| heaters I have on max, I'm nowhere near as comfortable as
| in properly built and heated apartments in my home place
| (actually when visiting friends in Poland in winter I'm
| almost overheating!).
|
| Basically half of the year it's quite uncomfortable to
| stay at home for prolonged time: for ~4 months a year at
| winter; then again for ~2-3 months at summer (+26C at
| home with blinds down unless you put aircon on max for
| hours). Kinda suboptimal for WFH to be honest :)
| inglor_cz wrote:
| I have an acquaintance in Madrid. Visiting her, I never
| know what to prepare for.
|
| An Easter visit was miserable, because the condo building
| did not even have central heating. With night
| temperatures around 5 degree Celsius, I could barely
| sleep.
|
| Then comes the summer and 40+ Celsius is at least as
| unbearable...
|
| Spanish construction standards are pretty ascetic.
| madaxe_again wrote:
| Portugal manage to be even worse. You'll be stood there
| in someone's kitchen wearing a coat and gloves, watching
| your breath condense, and they'll be like "oh but we
| don't get cold winters like you do in the northern
| countries". That's the rationale. The reason is actually
| more likely financial.
| [deleted]
| throw0101a wrote:
| > _It is interesting that you insulate under the house._
|
| This is part of the building code in many areas: do a search
| for [under] "slab insulation".
|
| * https://www.buildingscience.com/documents/information-
| sheets...
|
| * https://www.finehomebuilding.com/project-
| guides/insulation/i...
|
| It should be at least R-10 (RSI 1.8):
|
| * https://www.youtube.com/watch?v=O2dNp9bicSk
|
| * https://www.youtube.com/watch?v=XKp0wRzvR-g
| leobg wrote:
| Exactly. Talking about thermal mass!
|
| There's also the movement of underground houses. They use the
| ground for cooling in summer and for insulation in winter.
| Also it apparently makes for great noise reduction, in spite
| of having lots of windows, light and views.
|
| See the book "Recovering America: A More Gentle Way to
| Build".
| swader999 wrote:
| Underground houses can be a nightmare dealing with water
| infiltration, codes and the power of soil.
| poseva wrote:
| Really interesting. I've read about also "foundation
| insulation skirt" that allows you to create a warmer earth
| mass under the house.
|
| To be honest this was the biggest "complaint" that others had
| in regards of how a built the house, the general knowledge
| says that the earth is warm and you don't need to insulate
| against it... but the earth is maybe 5-10 degree, of course
| warmer than outside -5..-10 but still a lot colder than what
| we want inside the house, 20,21 degree C.
| tejohnso wrote:
| Insulation under the home, and skirted around it. You may
| be thinking of a Frost Protected Shallow Foundation[1]. A
| nice alternative to excavating in order to get below the
| frost line. I dream of doing this as part of a self built
| small passive house project.
|
| [1]: https://www.greenbuildingsolutions.org/blog/frost-
| protected-...
| swader999 wrote:
| ICF construction where the foundation form is Styrofoam
| Lego like blocks that concrete is poured into achieves
| this shallow and in full basement hooded. A lot more
| homes in Canada use this approach now.
| jaclaz wrote:
| That depends on how deep you dig, but of course going deep
| enough has a cost that may be far greater than the kind of
| insulation you used.
|
| The 20-25% of increase in cost is a good proxi (from my
| personal experience I would have said 25-30%), but, from an
| economical standpoint it should be compared with savings
| over time (in the same region).
|
| To give you an example in Italy, last time I calculated it,
| this 25-30% increase of costs corresponds - loosely - to
| the costs of heating for 20 years or so (bar the crazy
| increases in prices of energy that just happened), so it
| becomes more a "philosophical" choice than anything else to
| go for passive or almost passive.
| Sankozi wrote:
| 5% return per year (or more in case of price changes or
| regulations forcing you to change heating source) does
| not seem that "philosophical".
| jaclaz wrote:
| I don't understand fully your way of reasoning.
|
| A normal house costs - say - 200,000 "units" (dollars,
| euro, whatever).
|
| Making it "energy saving" costs an additional 60,000
| units.
|
| In 20 years time you will be spending 60,000 units (3,000
| per year) less for energy costs (and here we are assuming
| that ventilation and heating/cooling machines in the
| "better" house have the same maintenance costs than the
| ones in "normal" house, whilst usually, since they are
| more complex systems they tend to be more expensive).
|
| You essentially have a "break even" point 20 years in the
| future, from there onwards you start saving money.
|
| First thing, you need, now, 260,000 units instead of
| 200,000 (and not all people may be able to afford this).
|
| Then, if, for whatever reasons, you don't use the house
| at all times in these 20 years, or you need to sell it
| before that time you are unlikely to fully get the
| savings.
|
| Additionally, in less than 20 years time it is possible
| that someone comes out with a mega-para-hyper-ultra
| climatization device that makes yearly energy costs go
| down by (say) 90%.
|
| So, if you want to do the "right thing" from a
| climate/energy savings point of view, by any means choose
| to invest in a passive house, but it remains essentially
| a "philosophical" decision, not an economical one.
| ClumsyPilot wrote:
| "You essentially have a "break even" point 20 years in
| the future, from there onwards you start saving money."
|
| That's exactly how a 5% roi investment works. There is
| nothing unusual here.
|
| "in less than 20 years time it is possible that someone
| comes out with a mega-para-hyper-ultra climatization
| device that makes yearly energy costs go down by (say)
| 90%"
|
| And it's possible second coming of Christ will happen, or
| an asteroid will fall, and you'd be better off soending
| money on hookers and cocaine.
|
| A plan that relies on some unrelated events to solve your
| problems is not a plan. Why bother planning at all then?
| renewiltord wrote:
| This was a problem that hit the first solar adopters.
| Their break-even was so far in the future because the
| technology really ramped up later. Of course, one could
| argue perhaps that wouldn't have happened without the
| adoption. And perhaps argue against that again that it
| was gov subsidies that really pushed solar to primetime.
| empiricus wrote:
| Not only "philosophical", better insulated houses are
| also more comfortable.
| jaclaz wrote:
| Sure, but not all houses are built for "you" to live in
| perpetually.
|
| You build a house according to the minimal requirements
| of your local codes/norms.
|
| If you next year go to another city you may either sell
| the house or rent it (at average market value).
|
| You build a "passive house".
|
| If you next year go to another city you may either sell
| the house or rent it.
|
| Do you believe you can easily get 30% more rent or sale
| price because it is passive?
| Retric wrote:
| It's rather pointless to go through the effort of
| building a house if you don't expect to live in it for
| very long. So, the minimum standards should only be
| relevant to people building homes for sale.
|
| As to insulation, it's very cheap to add some form of
| solar heating outside of the arctic but cooling always
| takes energy.
| jaclaz wrote:
| What you expect may be different from what will
| eventually happen, and since the vast majority of houses
| are actually built by people that intend to sell them
| (builders), those make the market price, and - at least
| now - a passive house valued 30% more than average market
| is not easy to sell or rent, maybe this will change,
| maybe not.
| Retric wrote:
| You can very much rent a passive house for significantly
| more by including heating and cooling costs into the
| rental price. People can't see what your heating bills
| are but they can compare with other properties that
| include heating.
|
| Actual price differences at time of sale should be
| nowhere close to 30% not only because that's an insane
| difference in construction costs but also because land
| isn't free. A 200k house on 200k of land vs a 260k house
| on 200k of land isn't a 30% difference in final price.
| jaclaz wrote:
| Still it remains 60K difference, or 20 years at 3K.
| Retric wrote:
| Assuming it is actually 60k, where in reality insulation
| is cheap. Having giant windows is useful for passive heat
| gain, but their mostly installed for aesthetics not
| practicality. Which means aesthetics are also increasing
| home values.
|
| In terms of pure economics an extra 15k in insulation and
| 15k for a solar hot water system gets you further at much
| lower costs by actually providing hot water for showers
| not just lowering heating bills.
| jaclaz wrote:
| I think you are downsizing the project, from investing
| 60K to save 3K/year to investing 30K to save 1.5K/year.
| Retric wrote:
| No, I am saying you would save that much money more
| cheaply via other methods.
|
| Sure, saving 3k/year on heating costs for a single family
| home is extremely high. An average 1,800sf house in
| Massachusetts on $1.87/therm natural gas is only
| projected at $1,243 / year in heating bills for
| 2021/2022. That said you can always build a larger house,
| so saving 3k/year isn't impossible it's just much easier
| when you include better methods to collect sunlight than
| covering a side of your house in giant windows which have
| low R factors because their giant windows.
| maxerickson wrote:
| If you step back a bit, it makes sense for society to
| push for the construction techniques that minimize the
| lifetime cost of the building. Here, buildings typically
| last for much longer than 20 years.
|
| And then there's the whole thing where energy costs may
| not be fully priced into the use.
| jaclaz wrote:
| Sure, but then that is a "political" decision at
| government level, not your "free" choice.
|
| It is clear that the (good) trend is towards mandating
| "better" insulation (and thus less energy consumption)
| but it is not like a government can say "ok, starting
| tomorrow all new houses must be passive", as that
| translates to "ok, starting from tomorrow price of all
| new houses will increase by 30%".
|
| They are introducing - little by little - minimal
| requirements, and introducing in parallel some (BTW badly
| implemented at least here in Italy) economic incentives
| to better existing houses but it will take many years
| before they can impose "only passive" houses, and in any
| case, "new houses" are such a trifling percentage of
| existing buildings that they won't make a dent in the
| overall energy consumption, it is much more effective,
| given the amount to slightly better the much larger
| amount of existing buildings.
|
| Also it is not as easy as it seems, for the last 10-20
| years a number of houses have been built in the (at the
| time) energy classes A-B-C without mechanical
| ventilation/heat exchangers, with - let's call them "not
| fully tested" - construction methods and now that they
| are aging they show the problems emerging
| (humidity/mould, maintenance of windows, decay of
| insulation packets/facades, etc.), as often happens with
| new technologies.
| beerandt wrote:
| >construction techniques that minimize the lifetime cost
| of the building. Here, buildings typically last for much
| longer than 20 years. And then there's the whole thing
| where energy costs may not be fully priced into the use.
|
| It goes both ways. Investing in capex has to be balanced
| against potential capex and opex market changes, not just
| today's market.
|
| Unless that 0% rate gets passed onto you, there's a
| fairly rigid payback wall at 30 yrs where no amount of
| investment is going to make financial sense. (It's why
| despite loan terms growing for everything else, mortgages
| are still capped at 30 yrs.
|
| What happens when the market is flooded with cheap
| renewable electricity, as is promised? Suddenly your
| payback period is extended beyond what makes sense.
|
| Or advances in technology result in a cheaper, better
| insulation material?
|
| And then there's the potential external costs of not just
| energy, but material and construction. It wasn't that
| long ago that asbestos singles covered nearly every new
| house because of its fire resistance and insulating
| properties.
|
| The cost there also seemed to pay for itself, until we
| discovered the true cost of asbestos mitigation and
| removal.
| baq wrote:
| did you include heating costs rate of change growing?
| (i.e. prices rise more % yoy with each year?)
| markvdb wrote:
| > It is interesting that you insulate under the house.
|
| Near our place in the countryside, required foundation depth
| is 1.4m to protect from frost heave. Use an insulated slab
| and that requirement goes away. The insulation keeps the heat
| in the ground. It protects the ground under the house from
| freezing.
|
| Nobody cares about regulations here, but they do about
| getting proper foundations...
| lelanthran wrote:
| > The insulation keeps the heat in the ground. It protects
| the ground under the house from freezing.
|
| If it is preventing the ground under the house from
| freezing, then it is supplying heat to that ground. That's
| a energy-negative process - some of the heat you generate
| is used to maintain the warmth of the ground.
| markvdb wrote:
| Au contraire, my dear Watson.
|
| Without under-slab insulation, the heat emanating from
| the ground below the house escapes very quickly. This
| heat we don't generate. It occurs naturally. This is
| about using the naturally escaping heat to keep the
| ground under the house from freezing, about raising the
| frost depth.
|
| This technique is especially interesting for holiday
| homes not permanently heated in northern climates. It's
| fairly standard in Scandinavia, up and coming in the
| Baltics, but less known in the US.
|
| In the US, it's usually called FPFS or frost protected
| shallow foundations. [0]
|
| [0] https://www.ncei.noaa.gov/products/land-based-
| station/frost-...
| jounker wrote:
| Some of your heat is always going into the ground. The
| insulation prevents it from dissipating into the
| environment.
| mrweasel wrote:
| > It is interesting that you insulate under the house.
|
| Isn't that pretty normal, I mean maybe not three meters down,
| but modern foundations are required to be isolated in many
| places. The legal requirement in Denmark is at least 300mm of
| isolation under the house.
| 8fingerlouie wrote:
| And that's not a new thing either.
|
| In my 1970's house we have 150mm insulation under the house
| from the original build, 150mm in the walls and 200mm on
| the roof.
|
| We added another part to the house a few years ago, and
| that was 300mm insulation in floor/walls/roof. Since the
| walls are made of brick with a depth of 7cm, it means the
| walls are 7+7+30= 44cm thick (plus some "slack")
|
| Even my 1980's summerhouse has 100mm insulation in
| floor/walls/roof.
| jmrm wrote:
| That depends of the the place where you live. In middle to
| the south of Spain, the floor of houses are normally made
| of marble (or other ceramic material) slabs on top of a
| little layer of some glue cement, on top of the armoured
| concrete slab foundation, but on the north is a lot common
| to have wooden floors with air chamber of a similar size.
| kitd wrote:
| It is indeed normal. I mentioned it by way of an intro to
| the unusual alternative I saw.
| AtlasBarfed wrote:
| So with home solar panels and storage getting cheaper and
| cheaper and better and better, where is the optimization point
| of investing in better insulation vs just buying more solar
| panels?
|
| Especially if the solar panels may produce profit on sunny mild
| days about 40-50% of the year if there is reverse metering and
| the like?
| throw0101a wrote:
| > _What is the big difference between houses built in North
| America and Europe is that the European houses are built using
| concrete and masonry which give them a lot of thermal mass
| which is crucial to this kind of builds._
|
| Here's a 500 sq. m. (5000 sq. ft.) house built with heating
| equipment that uses 1800W (the equivalent of a hair drier):
|
| * https://www.youtube.com/watch?v=_vul4vMFdkA
|
| The same person building his own personal home up to Passive
| House standards:
|
| * https://www.youtube.com/watch?v=mBOvflXoWlw
|
| You do not need concrete+ and masonry to make homes efficient.
| Switching from using 2x4s @16" off centre (OC), to 2x6 @24" OC
| ("advanced framing") would allow for less wood use, less
| thermal bridging, and more cavity space for insulation.
|
| + It should be noted that concrete creates a lot of CO2
| emissions, as does baking bricks. Growing wood on the other
| hand is a way to sequester carbon.
| poseva wrote:
| I agree, you do not need concrete and brick but you also need
| to take into account the local traditions. For ex. building a
| wood house (framing or CLT) would have cost much more than
| concrete and bricks and was also much more prone to errors
| because of the builders lack of experience, at least in my
| area and country.
|
| Recently in Romania it really took of building houses using
| CLT (cross-laminated-timber) but it costs so much more than a
| regular brick and mortar house that few people afford it.
|
| When -15 outside and 20 degrees inside, my house requires
| 2000W to keep the balance. This kind of simulations are done
| using PHPP package from PassivHaus Institut.
|
| L.E. What I wanted to point out, thermal mass can have a huge
| impact on the house energy footprint.. to give you an
| example, today and tomorrow will be sunny days and this will
| drive my interior temp to about 23-24 degrees, this heat will
| heat-up the masonry and slabs and then give me back the heat
| in the next days when there will be no sun.
| throw0101a wrote:
| Wood is fairly inexpensive in North America because there
| are still many forests (especially in Canada).
|
| There is nothing "inherently better" with one material over
| another for most applications. A good structure mostly
| depends on proper drainage and cladding to protect against
| UV rays and bulk water (precipitation), good air tightness
| (with mechanical ventilation for filtered, tempered fresh
| air), and high insulation.
|
| * https://www.buildingscience.com/documents/insights/bsi-00
| 1-t...
| bluGill wrote:
| Modern codes have moved back to 2x4, then they put continuous
| foam on the outside of that to make the total the width of
| a.2x6 wall. Wood is not a great insulator and you have to
| have some
| throw0101a wrote:
| > _Modern codes have moved back to 2x4, then they put
| continuous foam on the outside_
|
| Codes do allow for only external insulation, but it it also
| possible to have some exterior "continuous insulation" with
| the remainder being in the wall cavity.
|
| The thicker the exterior insulation, the trickier it can be
| to attach it to the wall and then also have mechanical
| fasteners for your external cladding.
|
| * https://www.buildingscience.com/documents/insights/bsi-00
| 1-t...
|
| * https://www.buildingscience.com/documents/building-
| science-i...
|
| However, AIUI, using 2x6s reduces the number of studs
| needed and so would generally reduce the cost on average
| from both a material and labour perspective (even if 2x6s
| are slightly higher each).
|
| * https://www.buildingscience.com/documents/insights/bsi-03
| 0-a...
|
| * https://buildability.ca/wp-
| content/uploads/2017/05/M400-Adva...
|
| * https://www.energystar.gov/ia/home_improvement/home_solut
| ion...
|
| * https://www.protradecraft.com/article/advanced-framing-
| dos-a...
|
| And it's not like it's a new technique: it's been around
| for (at least) forty years.
| bluGill wrote:
| I should have said modern building and not codes. there
| are a lot of ways to satisfy good codes, 2x4 tends to be
| cheapest for single family houses, but others are not far
| behind and may be worth it in the long run. Consult a
| proper engineer if you are building a house of course.
| Mvandenbergh wrote:
| Moving insulation outside the frame also helps reduce the
| effect of thermal bridging although with timber that's not so
| important as it is with steel.
| oldsecondhand wrote:
| High thermal mass is definitely more energy efficient in the
| summer, when you can "store the cold" from the night into the
| next day.
| bserge wrote:
| k__ wrote:
| A friend of mine, who is an architect, told me the technology
| is ripe to build houses that produce even more energy than they
| consume, but people simply don't want to live in them.
|
| The article talks about "using the best windows", the problem
| my friend saw in many of such houses was simply that the
| dwellers would either open the windows too often, losing all
| the heat, or feel miserable because they weren't allowed to
| open the windows. A pure psychological effect of course, even
| with the best ventilation people still had the urge to open a
| window and felt bad if they couldn't.
| driverdan wrote:
| > the technology is ripe to build houses that produce even
| more energy than they consume, but people simply don't want
| to live in them
|
| It's called solar. Unless the house has a small footprint
| most can fit enough solar panels to more than cover their
| energy use.
| changoplatanero wrote:
| how do you ventilate without losing all the heat?
| thatguy0900 wrote:
| https://www.energy.gov/energysaver/whole-house-ventilation
|
| Energy recovery ventilation systems gives a good
| description
| jhgb wrote:
| Recuperator ventilation, presumably?
| CrazyStat wrote:
| Heat recovery ventilation [1] can bring in fresh air and
| output old air while recovering the vast majority of the
| heat.
|
| [1] https://en.wikipedia.org/wiki/Heat_recovery_ventilation
| throwaway984393 wrote:
| I recently lived in a house with no external ventilation in
| one big room. Huuuge windows looking out onto a huge backyard
| full of trees and flowers. Yeah I missed being able to open
| the window and hear the birds. But then when lawnmowers
| started buzzing and dogs started barking, and later when
| winter hit, I was quite glad for the peace and quiet and no
| need to open them!
| pnutjam wrote:
| I never open my windows unless I'm trying to air out
| something.
| spookthesunset wrote:
| > A pure psychological effect of course, even with the best
| ventilation people still had the urge to open a window and
| felt bad if they couldn't.
|
| I wouldn't want to live in a house where I couldn't open the
| windows all the way. Near-perfect energy efficiency is
| something to strive for but there is something to be said for
| being able to open the window and get a nice breeze blowing
| through the house. Even if it isn't the most energy efficient
| it's okay with me.
| spookthesunset wrote:
| > A pure psychological effect of course, even with the best
| ventilation people still had the urge to open a window and
| felt bad if they couldn't.
|
| I wouldn't want to live in a house where I couldn't open the
| windows all the way. Near-perfect energy efficiency is
| something to strive for but there is something to be said for
| being able to open the window and get a nice breeze blowing
| through the house.
|
| Even if it isn't the most energy efficient it's okay with me.
| I mean if we really wanted to get good energy efficiency we'd
| just remove all the windows completely. But we don't because
| we design building for the enjoyment of humans, not just for
| energy efficiency.
| bawolff wrote:
| I'm kind of curious what weather range they are talking about.
|
| As someone from Canada, i somehow don't think this would work
| over here in the -40 winter.
| dx034 wrote:
| I lived in a PassivHouse in Germany. Didn't need to heat if it
| was more than 4C outside (less if more people were at home). I
| never experienced -40C, but at -20C it worked fine. Probably
| the only time all heating had to run to some degree 24/7. I'm
| sure that -40C would've been fine as well.
|
| In the end it all doesn't matter. You build the house to some
| standard and then design the heating system to be able to cover
| thermal loss for the expected temperature range. In Canada
| you'd probably just add twice as much heating as you would in
| most of Europe. But especially at those temperatures, very well
| insulated homes will save a ton of money.
|
| The only part that kind of worked less well at very low
| temperatures was the heat exchanger for the ventilation system.
| It didn't run at full capacity if it was well below freezing.
| But I guess there are other systems out there which are
| designed for -40C as well.
| timonoko wrote:
| Does not work at all. In Finland we have disastrous situation
| with pre-90's "Bottle"-houses with air-tight insulation. Not
| enough circulation and dangerous mildew blooms.
|
| All this lower 50's German crap about heat pumps and heat
| exchanges does not make much sense. Once again. Not a surprise.
| masklinn wrote:
| Canada was actually one of the early study and proving grounds
| for passive houses, due to the oil shock (look up the
| Saskatchewan Conservation House).
|
| Sadly much like most other such actions, they were quickly
| discarded once the shock receded, but the german Passivhaus
| Institut was actually founded on the basis of that study and
| model house.
| [deleted]
| dakna wrote:
| While I certainly dream of building a true passive house, it is
| much more reasonable to follow the Pretty Good House approach, in
| it's current 2.0 version described here:
| https://www.prettygoodhouse.org/pgh-20
|
| As with most engineering efforts, the last 20% of optimization
| tend to be costly. But covering the basics (mainly around
| insulation and air-sealing) has a huge impact already without
| increasing upfront costs by the same ratio.
|
| Also the wall/roof assembly needs to match the climate for the
| region, mainly because of the dew point and how it relates to
| temperature and moisture differences between inside/outside.
| https://en.wikipedia.org/wiki/Dew_point
| meerita wrote:
| Last year I rented a reformed old fabric and I cannot be more
| happy with. The building is really well done now and it's energy
| efficent. I usually turn on the heat for a couple of minutes and
| the flat stays warn for hours. The windows are really good not
| only to keep the heat but also letting light in and blocking 95%
| of the sounds.
| dt3ft wrote:
| I'd love to see them try this in Sweden :)
| Moru wrote:
| First one was built 20 years ago but getting more popular after
| 2010. You can order them, it's a building standard so does not
| require anything from you except money. But they say it's not
| that much more expensive than a normal swedish house since we
| already have a lot of isolation and 3 glass windows as standard
| for the climate.
| 2rsf wrote:
| So what is the difference and why does my modern Swedish
| house, with heat recovery ventilation and east-south facing
| windows consumes more energy to heat?
| Moru wrote:
| More than what?
| dredmorbius wrote:
| Fairbanks, AK:
|
| https://yewtu.be/watch?v=Xen_VWyDezY
| bjoli wrote:
| Two years ago I spent a week in a passive house near Pitea. The
| outside temperature was -25c and heating the house was done
| exclusively using an accumulation tank of solar heated water
| (yes. It worked just fine in -25 if the sun was shining for
| more than 2 hour a day).
|
| The only problem was that it got too hot when we were making
| food or running the tumble dryer.
|
| Heating for that house was between 500 and 2000 kwh/yr
| depending on how much the sun was shining.
| m_eiman wrote:
| There are plenty of passive houses in Sweden.
| alkonaut wrote:
| They are quite different in construction though. The
| insulation on this house corresponds to a garage in the
| nordics today, or how the building code looked in the 1970s
| and 1980s. Today the code requires twice this much insulation
| for a _normal_ home (around 300mm), and it 's still nowhere
| near a passive one.
| fy20 wrote:
| Come to Lithuania (we have winters of -25C and summers of 35C).
| All new homes have to be build to a building code that actually
| exceeds Passive House in some cases. In our apartment (built
| 2016) we don't even turn on the heating until it gets close to
| 0c outside.
| locallost wrote:
| One well known example of modern efficient houses is the one
| Amory Lovins built in the Rocky Mountains in the US. It gets
| quite cold there, yet he likes to point out he grows bananas in
| the house.
| dredmorbius wrote:
| Can confirm, I visited RMI in the early 2000s.
|
| The entire structure is built with the climate and site in
| mind. Large south-facing windows, thermal mass in the floor
| and walls. At the time, the major energy draw was
| laserprinters, given that the xerographic process used relies
| on a heating element kept at about 400F. Switching to inkjet
| printers was a major energy gain (though ink costs might make
| this a financial wash).
| _Microft wrote:
| Note that the sun is towards north in NZ.
| dghughes wrote:
| I really think many people don't pay enough attention to
| insulating homes they think solar panels, heat pumps etc.. But
| don't think of why the house is too hot or too cold. It's all
| just moving energy around cold is absence of heat but you hear of
| people say "cold is coming in" really it's heat escaping.
|
| I'm going to try my hand at insulation my parent's home. Dad died
| last year he built the house and everything in it and on it. He
| was sick for 15 years so maintenance was difficult.
|
| I'm looking at Rockwool for the attic most heat is lost through
| the roof. The pull down stairs are terrible for heat loss. Heat
| bridging is also what I want to tackle too I'll cover joists
| perpendicularly.
|
| Stuffing the attic with insulation is easier than solar or a heat
| pump. For now.
| elliottkember wrote:
| If you are interested in this, you may like The Zen Of Passive
| Solar Heating: http://www.iedu.com/Solar/Panels/ which is one of
| my favourite online project logs.
| markvdb wrote:
| If you have a large enough plot, consider building a home out of
| jumbo straw bales. Super insulating, easy and fast to build,
| cheap and eco.
| Terry_Roll wrote:
| Its all very well using environmental energy sources to heat and
| cool a building, but very little attention is given over to
| clearing the air. Besides the pollutants from cleaning products
| and product breakdown, CO2 levels inside a building can have a
| stimulating effect on the body, which kind of destroys the
| purpose of a relaxation of a home.
| surfmike wrote:
| The passive house standard requires mechnical ventilation using
| heat exchangers to minimize energy loss.
| http://tepperarchitects.com/?p=522
| Terry_Roll wrote:
| Yeah but what is a healthy Air Changes per Hour (ACH)?
|
| The building regs here in the UK are a bit all over the
| place, I had to direct some questions to the local authority
| planning dept because their legislation was like a poorly
| written computer program and they couldnt answer the
| questions.
|
| The legislation doesnt quantify the risks properly imo, at
| least here in the UK.
| grey-area wrote:
| This article is about passive houses, which have very good
| ventilation (they have to, because the building is
| hermetically sealed apart from the HVAC). So the air
| quality is much better than normal homes without a
| dedicated ventilation system.
| jakewins wrote:
| The houses I've seen control the exchange rate with air
| quality sensors - so, if you are having a party, the
| ventilation speeds up, and when the house is empty it slows
| down.
|
| That said, in the US the ACH rate is recommended at 0.35 by
| ASHRAE, see https://www.epa.gov/indoor-air-quality-iaq/how-
| much-ventilat...
| Terry_Roll wrote:
| Yeah but its not measuring the quality of the air. Houses
| are just passive particulate collecting devices, ie
| particulates travelling on the air outside, move into the
| house, meet a stationary or slower moving body of air,
| lose momentum and velocity and thus succumbs to the
| effects of gravity and hits a surface.
|
| Considering woman have traditionally been the one's
| cleaning the house for the living abode for hundreds of
| years, why havent they come up with something better to
| filter the air inside a property seeing as there is this
| push to get females into STEM?
| Cthulhu_ wrote:
| There was a big Thing in the neighbourhood I live in (built
| ~15 years ago) where this kind of two-way ventilation system
| did not work correctly; it did not have the right capacity on
| the one hand, and was too loud on the other (meaning people
| shut it off). But they're so well insulated that that was not
| an option.
|
| My house has a one-way ventilation system, air is sucked in
| through vents in the windows. We keep it at the lowest
| setting though, again because of noise, but that seems to be
| all right for us.
| goodpoint wrote:
| > CO2 levels inside a building can have a stimulating effect on
| the body, which kind of destroys the purpose of a relaxation of
| a home
|
| Citation really needed.
| Terry_Roll wrote:
| You know where google scholar, pubmed and wiki is? Or do you
| want to get into a discussion about under-carboxylation and
| dietary intake of nutrients, and CO2 blood saturation levels?
|
| https://en.wikipedia.org/wiki/Hypercapnia#Tolerance
| goodpoint wrote:
| > You know where google scholar, pubmed and wiki is?
|
| I know them quite well but this is a conversation on HN and
| people should back their claims here.
| Terry_Roll wrote:
| Well you can see that breathing is stimulated with rising
| CO2 levels, everyone knows this whether they have
| exercised or held a non-permeable bag over their head.
|
| Its interesting because Climate Change aka rising CO2
| levels will stimulate the population globally which then
| presents a new area of concern for authorities who like
| to keep control of a population. Hadnt thought of that
| until now!
| shalmanese wrote:
| People fail to appreciate how much leveraged financing affects
| the design of houses. If you pay 100% for a house and you decide
| to build something only you appreciate using 10% of your budget,
| you will lose 10% of your investment when selling the house. If
| you put down 20% and have the bank finance 80%, then the same
| decision will wipe out 50% of your investment. This means for
| financed houses, "resale value" becomes the preeminent decision
| affecting the design of a house.
|
| In Economics, this is known as a "Keynesian Beauty Contest" [1]
| where your job is to predict what everyone else predicts will be
| the most popular option and Keynesian Beauty Contests can get
| _weird_.
|
| eg: It's quite possible that you might personally hate granite
| countertops but still feel the need to put a granite countertop
| in your home because you believe it will help the resale value of
| your home. It's quite possible for _everyone_ in a community to
| all hate granite countertops but for everyone to still put
| granite countertops in their home because they believe everyone
| else loves granite countertops. It 's quite possible for
| _everyone_ in a community to hate granite countertops and to
| _know_ that everyone else hates granite countertops and _still_
| make the economically rational decision to put a granite
| countertop in their house to help with the resale value.
|
| A lot of "economically irrational" housing decisions are driven
| by this core transformation via Mortgage Backed Securities of a
| house from a consumption based purchase of a place to enjoy
| living into an investment asset that dominates most people's
| finances.
|
| It's only in houses built for the independently wealthy that
| don't really care about the future resale value of their houses
| that a lot of the good building science expertise still lies.
| That's why, paradoxically, in countries much poorer than the
| US/UK/Aus/NZ, you see much better building quality because their
| finance systems are also less developed.
|
| [1] https://en.wikipedia.org/wiki/Keynesian_beauty_contest
| gruez wrote:
| >That's why, paradoxically, in countries much poorer than the
| US/UK/Aus/NZ, you see much better building quality because
| their finance systems are also less developed.
|
| source? China isn't well known for their well built buildings
| for example.
| oldsecondhand wrote:
| I can't give you hard stats, but in Hungary in the 80s (i.e.
| socialist times) people were building their own houses in the
| villages (i.e. with the help from extended family only hiring
| tradesman when you don't have that trade in family) so there
| was little reason to cut corners. It also avoided the cookie
| cutter look of American suburbs. These are brick houses, so
| they're quite sturdy, and could be modernized by adding
| external insulation. Most of these houses were built with
| double glazed windows to begin with, so I was pretty
| surprised that in Britain or Spain it isn't default.
| netjiro wrote:
| Some guidelines for better, healthier, low energy, low cost house
| construction:
|
| Understand basic physics.
|
| Avoid the architecture-of-the-week construction trends.
|
| Set your targets: Size vs cost? How long do you expect to live
| there? Price of energy vs better insulation? Maintenance: type,
| frequency, amount, cost? How important is it for you to reduce
| the environmental impact? Start small and expand later, or start
| big and later rent out part of the house?
|
| Stay open minded about the solutions and designs. This makes a
| huge difference. The building codes and municipal restrictions
| are often the most limiting factors on how "good" a house you can
| build. Don't add _unnecessary_ restrictions on top of that. Look
| around at different solutions, not just what the local
| construction companies offer. Travel and see how things are
| solved in other countries.
|
| Use simple construction methods and design. Reduce the number of
| construction tasks necessary, and make each task simple. A
| significant real world problem with normal passivhaus
| construction is that while designed well, they are often very
| complex to actually build, and small mistakes by the construction
| crew can have a large impact on the energy requirements as well
| as cause health hazards.
|
| Well insulated windows, walls, floor and ceiling also drastically
| improve the comfort feeling of the house, not just the energy
| bill. When done right and coupled with properly designed
| ventilation they also improve the health aspects of the indoor
| environment.
|
| Many low energy houses built today require that the indoor air is
| kept very dry when the temperature difference between inside and
| outside increases. This has a lot of negative health effects. By
| choosing different insulation and interior materials they can be
| made to allow high indoor humidity. Your lungs, throat, nose,
| eyes and skin will thank you. Internal humidity around 50-60%
| also reduces air transmission of many viruses.
|
| Thermal mass is mentioned in some other posts here. Make sure to
| place it inside the insulation layer, not on the outside. Water
| and stone have similar high volumetric specific heat capacity. By
| using water circuits and storage, the mass can be moved out of
| the way, and often coupled to very efficient heating/cooling
| systems.
|
| We have developed a construction toolbox for houses and
| industrial buildings with very low total life cycle CO2
| footprint, suitable for climates down to around 0C annual average
| temperature (northern Scandinavia, around the polar circle). They
| are fast and cheap to build and provide superb internal
| environment. If you're interested in more info I'm happy to
| share. You can ping us at StoneWoodGreyBeard at gmail.
| morsch wrote:
| The article shows off snazzy housing for wealthy people, but as
| far as I know all new housing finished in the EU as of 2021 is
| supposed to be built to these standards. So it's not restricted
| to architecture magazine, it's just regular houses.
|
| See e.g. https://www.igbc.ie/nzeb/
| rsynnott wrote:
| nZEB isn't quite the same thing as a passive house; a well-
| built passive house would qualify as an nZEB, but you could for
| instance, build an nZEB that had reasonably high thermal losses
| (thus not a passive house) which it compensates for with loads
| of solar panels.
|
| That said, in practice most nZEBs probably will be passive
| houses or close; it's probably the most practical way to meet
| the requirements in most cases.
| jve wrote:
| Actually, article complains that Building Code is pretty low
| standard in NZ and that non-wealthy suffers as they live in
| not-so-well insulated houses.
|
| But speaking from northern EU country - yeah, I don't see
| anyone here building non-insulated houses.
| naikrovek wrote:
| In 1989 my grandparents built a home with 12" thick walls (6" was
| normal at the time, in the area) and carefully vapor-sealed the
| entire house, taking _extra_ special care to avoid holes which
| would let air move through the house in an unplanned way.
|
| They paid extra (a lot extra) for the highest insulation value
| available for the fiberglass rolls they installed in the outside
| walls. They double-stacked the insulation, as well, which is why
| they built the walls so thick.
|
| They poured the basement foundation on top of layers of foam
| insulation, and used piers (I don't know what they're called)
| down to the bedrock for structural integrity; the majority of the
| outside of basement floor was in contact only with insulation.
| Only 16-20 8" columns went through the insulation down to bedrock
| and could be good conduits for heat to the earth. All of the
| walls in the basement were double insulated from the earth they
| held back.
|
| That house was heated entirely by the heat that the water heater
| released through its insulation. Once or twice a year they would
| light a candle on the dining room table, to bring the heat back
| up if it ever got below what they felt was comfortable. Most days
| they had windows cracked open on opposite sides of the house in
| the middle of winter because it got too hot even with the furnace
| turned off entirely. It was never less than 75F in that house,
| even when it was -15F outside. I spent months on end in that
| house, just wondering when the furnace would come on. It never
| did. Not once while they lived there was the furnace ever needed.
| They lived in Missouri, US.
|
| Years later my grandfather realized that he had left the petcock
| which allowed hot water to circulate to the radiator over which
| air was blown and heated to circulate heat throughout the house
| _closed_ for over a decade -- since the house was built. "I knew
| I wouldn't need this damn furnace. Building code requires it, and
| I fought that but lost."
|
| If you're careful, thoughtful, and determined, you can make a
| little bit of heat go a very long way. They were tired of paying
| heating bills. They paid to get rid of them, but they were rid of
| them.
| WkndTriathlete wrote:
| > In 1989 my grandparents built a home ... and carefully vapor-
| sealed the entire house
|
| In the upper Midwest there were a number of homes built this
| way in the 80s/90s. 10-15 years later they all had black mold
| (nasty health hazard) growing in the walls because moisture
| couldn't escape from the house. All homes are now required to
| have air-to-air heat exchangers for this reason.
| Reichhardt wrote:
| Its not moisture, its general ventilation. All houses should
| have formal ventilation systems to exhaust CO2 and control
| humidity secondarily.
| tigerlily wrote:
| > there is no excuse for New Zealand homes to be damp, cold or
| drafty
|
| Yet we build them this way over and over and over and over and
| over and over and over and over...
| bogle wrote:
| Lack of building regs?
| pdamoc wrote:
| My favorite approach remains the Dome of Visions -
| https://www.youtube.com/watch?v=1Bn2o-xyS6M
| pkdpic wrote:
| Cool project and name. Ive always been curious if domes like
| this become problematic in hot weather though or if they have
| some dynamic that makes them beneficial then too. Not sure how
| to google that but maybe someone knows.
| SenHeng wrote:
| I'm in the middle of building a PassivHaus. The building itself
| is mostly done and we're working on the interior. There are still
| a few gaps that haven't been plugged and the heat exchangers have
| not yet been installed. I'm above 800m elevation, snowstorms
| every weekend. It's cold here. My house also actually faces West
| instead of South, so I'm not getting much heat from the sun. This
| was a surprise to use because the previous house on the same site
| had the same orientation and was scorching during the evenings,
| it's amazing what a pair of Low-E triple paned windows can do.
|
| Despite all that, the builders manage to work inside the building
| with a single kerosene stove[0]. And the building stays
| comfortable for several hours even after the stove has been
| turned off.
|
| [0]: https://nimmi.jp/kurashi-stove/
| spiffistan wrote:
| How is the ventilation and air quality? I work in a passive
| house in and we're experiencing significant issues with the
| indoor air quality when the building HVAC turns low.
| yboris wrote:
| For heating a home efficiently, one approach is a _rocket mass
| heater_. It does require burning firewood, but if that 's an
| acceptable/desirable quality, this technology seems far more
| efficient than standard fireplaces.
|
| https://en.wikipedia.org/wiki/Rocket_mass_heater
| sambeau wrote:
| Is a stove like that not really dangerous in an air-tight
| house? Where do the fumes go?
| signaturefish wrote:
| Most air-tight houses have an integrated MVHR (mechanical
| ventilation with heat recovery) system, which is kind of the
| inverse of an HVAC setup. There's a constant small air
| current being moved through the house, and when it exhausts
| to the outside world a heat-exchanger captures as much heat
| as possible from the exiting air and uses it to heat the
| entering air. Airtightness means you can control where the
| air enters and exits, which means this trick is possible.
|
| All that being said, I'd expect a permanently-installed stove
| to have a flue (which results in the stove technically being
| a leak, but that's solvable). I assume the kerosene stove
| mentioned above is in use while the house is incomplete, so
| not yet airtight.
| inovica wrote:
| Sounds great. Do you have a blog or anything online about your
| project?
| osobo wrote:
| I'm looking into making a house sustainable right now and the
| windows are actually a point of contention. One side thinks
| super-high insulated (triple pane) windows are a waste of
| money, the other swears by them. Assuming the frame doesn't
| leak, does triple really make that much of a difference?
| [deleted]
| a_square_peg wrote:
| This depends on your house - heat tends to leak out through
| the lowest path of resistance so if you have a well-insulated
| house with leaky window, it would certainly be the case but
| without considering what the rest of the house is like, it
| would be impossible to tell how much they would help.
| andi999 wrote:
| Heat leaks out through all path of resistance not just the
| lowest. (The lowest might dominate though if it is orders
| of magnitude lower than the second lowest)
| jeffreygoesto wrote:
| For us it did. Estimated 2 degree Celsius on the inside
| during winter already make a big difference in comfort and
| how you will use the space in front of the windows.
|
| Windows, walls, ceilings and so on have to match of course,
| our house is overall well insulated.
| supermatt wrote:
| Depends on your climate and the heat differential between
| inside and outside. Triple glazing is effectively double the
| R-value of double glazing, so in a cold climate yeah..
| poseva wrote:
| You must also be careful on how you mount the windows. Have a
| look at the german standard called "RAL montage" to see that
| you need an inner and outer membrane and then have a look on
| where to mount the window inside the wall.. the best solution
| is to mount it outside the wall in the insulation, the second
| best solution is to align it at the face of the wall.
| mcot2 wrote:
| Get yourself a FLIR (the phone attached ones are not that
| expensive) and check for yourself. It is a great tool.
| liveoneggs wrote:
| they are worth it in cold climates if you use fixed or very
| fancy casement windows with maintained seals. Double-hung
| will just leak around frames and sides.
|
| Also ensure you use a good brand which will be around when
| you need a replacement and hope to get an actual match.
| dredmorbius wrote:
| As others have said, solutions depend on your climate, and
| especially on whether you principally have heating or cooling
| loads.
|
| For cold climates, designers such as Thorstein Chlupp (Rienna
| LLC, in Fairbanks, AK) rely on triple-paned _high emissivity_
| windows for solar _gain_ , and _external_ thermal shutters at
| night to reduce radiative loss.
|
| For warm climates, you'll want _low emissivity_ glazing, as
| well as awnings or landscaping which block direct summer sun
| while admitting light. For winter time, you can probably get
| by with internal thermal curtains in winter, though an
| external storm glazing or shutter may also be helpful.
|
| Having windows face the equator (that is, south-facing in the
| northern hemisphere, north-facing south of the equator) will
| increase light and decrease heat loss. Glazing on the pole-
| side of your home is generally reduced, and in sufficiently
| cold climates, eliminated.
|
| More than you'd ever want to know (2h26m video) here:
|
| https://yewtu.be/watch?v=Xen_VWyDezY
| olau wrote:
| In the house I'm living in, which was built in a transition
| point between making sure houses don't leak and the
| realization that you then need active ventilation, I have the
| problem that the windows are not insulating enough, so I end
| up with water condense on the inside when it's freezing
| outside. If you are going to replace the windows, I would
| definitely buy triple-paned, unless you only have a small
| temperature difference.
| atoav wrote:
| They can be a dream in terms of noise blocking as well.
| pomian wrote:
| Yes. Makes measurable difference. Especially big picture
| windows. Other things to consider: is the type of glass. In
| places like Arizona you may not want sunlight to get through,
| but further north, the sun can provide a great deal of heat.
| So you want transmissivity. To stop that in the summer, you
| have a overhang roof, far enough out, to block sun in summer
| but not winter. Also, be smart installing the window, to
| prevent leakage around the frame, lots of good tricks there.
| For example- Avoid tightness of frame.
| jaclaz wrote:
| Generaly speaking, yes, BUT the design needs to be taken into
| account.
|
| A window (good as it might be) is "worse" than walls (besides
| being much more costly), the modern design trends are for
| extremely huge windows, that (whilst they give much more
| light, which expecially in northern climates is a wanted
| feature) are a problem, from a thermal viewpoint.
|
| The typical size of windows in "normal" houses varies
| (depending on countries) like 1/8 to 1/12 of area of the
| floor of the room they are in, modern designs can be often
| 1/5 or 1/6, it is clear that the less amount of window
| surface you have the less relevant are its characteristics,
| and you have to consider also the effect of shutters or
| similar.
| fy20 wrote:
| Windows have a U or R value like insulation, so you can use
| that to compare.
|
| We are currently building a house and the triple glazed
| windows we chose have a U value of 0.9. The same manufacturer
| also makes double glazed windows which have a U value of 1.3.
| yoyopa wrote:
| yes, it's like wearing a sweater vs. wearing two sweaters
| ricardo81 wrote:
| I'm in the UK which has one of the oldest/energy inefficient
| housing stocks in Europe.
|
| After buying a house built in 1890 I've been made more aware how
| poor they can be. After replacing the old secondary glazed
| windows and replacing the old inefficient gas boiler, I'm moving
| onto replacing the front and back door, and insulating the
| suspended floor, walls and room in roof. The walls are solid
| whinstone about 600mm thick which I'd have expected to be a good
| insulator but in reality they're a thermal bridge.
|
| For generation, I've reserved a spot in Rippleenergy's next co-op
| turbine [0]. I've been looking into PV/solar thermal/solar
| battery combinations as well as heat batteries. Sunamp's looks
| interesting [1] and phase change materials in general. Living in
| a high latitude (Scotland) the benefit in Winter is more marginal
| but I'd be happy with simply covering the cost and having peace
| of mind where the energy came from. PVT panels look interesting
| if not well-known/scarce.
|
| There's so many parts to the answer it seems like energy advisors
| could be more of a thing in the same way financial advisors are
| plentiful.
|
| [0] https://rippleenergy.com/
|
| [1] https://sunamp.com/thermino-thermal-storage-for-domestic-
| hot...
| Mvandenbergh wrote:
| I work on energy systems modelling and how domestic thermal
| performance interfaces with that - the UK has not just "one of
| the oldest in Europe" it actually has the oldest in the world.
| Many European countries had a lot more post WWII construction
| so at least have cavity walls (even if in many cases not filled
| until later).
| cjrp wrote:
| My understanding was that cavities should actually not be
| filled, since they allow water to drain out. Is that
| incorrect?
| Mvandenbergh wrote:
| The issue is will the cavity system allow water to
| penetrate to the inner leaf which is bad and will cause
| internal dampness.
|
| Cavities can be carefully partially filled with some type
| of insulation which allows the water soaking through the
| brick to evaporate and drain back out.
|
| The standard technique is to use blown in EPS beads which
| allow for drainage downwards, reducing the chance that any
| water loading will make it through the insulation layer and
| to the inner leaf of the wall.
|
| Problems with cavity insulation are often caused by:
|
| -Treating walls which have a large amount of debris in the
| cavity, leading to water bridging
|
| -Over-filling cavities which also leads to water bridging
|
| -Treating walls with very large amounts of rain exposure,
| especially to driving rain for extended periods of time
| since this will lead to saturation of the cavity insulation
| system which may be unable to dry for months at a time.
| These walls should be externally insulated and clad
| instead.
|
| In the UK context for example, houses in Wales and parts of
| the English South coast, the whole Southwest, the East of
| Scotland, and most of NI are in zones 3 and 4 in terms of
| wind driven rain exposure.
|
| In zone 3 and 4, installers are required to carry out an
| assessment of site conditions and of cavity thickness as
| well as exterior wall finish. Older houses might have 50mm
| cavities, new properties often have 100mm or 150mm
| cavities. Obviously that reduces the changes of water
| soaking through.
|
| Approved Document C allows a full fill of insulation for a
| 75mm cavity on a fully rendered wall and on a 50mm cavity
| if clad with rain impervious material but requires 150mm
| for bare masonry.
| cjrp wrote:
| Thanks for the detail! I have a 1930s house with, I
| think, unfilled cavities. I've always been put off
| looking into insulating because it seemed potentially
| harmful.
| KaiserPro wrote:
| The next most effective thing to do is External wall
| insulation. However that'll mean that you'll loose the
| whinstone look. (unless you pay a _lot_ to get whinstone like
| shims put on after)
|
| The alternative is to have internal wall insulation:
| https://www.insulationsuperstore.co.uk/product/vacutherm-vac...
|
| This is as effective as ~150mm of rockwool, but only 20mm
| thick. So this can be stuck behind plaster/plasterboard.
|
| but its not easy to work with, or widespread yet.
| ricardo81 wrote:
| Yes, it's one of the top recommendations (internal wall
| insulation) on my EPC and have had a survey. 60mm PIR boards
| would be used. Turns out I wouldn't have to sacrifice much
| space but would have to pay a bit extra replacing the
| cornices.
|
| There are some regional grants in the UK that can cover a
| large portion of the amount. For me, it is PS7.5K, with the
| quote I received at PS9K. This would not have covered the
| kitchen or bathroom.
|
| Going by EPC recommendations and numbers alone, I can reduce
| my energy requirement by about 40%.
| rogalian wrote:
| Had to sign up for this. Take extra care to use appropriate
| materials for a house this age or you'll create more
| problems than you solve. Solid stone walls need to breathe!
|
| Make sure you've spoken with a surveyor specialising in
| heritage property too.
|
| PIR boards are almost certainly unsuitable.
|
| https://www.victorian-house.co.uk/ (be sure to pick up a
| copy of the Haynes Victorian House manual, it's a gem)
|
| https://www.lime.org.uk/community/boards-insulation.html
|
| I'm currently having to undo poor choices of modernisation
| on a building of the same age, which caused tremendous
| problems with damp.
| Dylanfm wrote:
| Another good resource is
| https://www.neighbourhoodconstruction.org e.g their page
| on Thermal Envelope > Bio aggregate
| https://www.neighbourhoodconstruction.org/bio-aggregate/
| ricardo81 wrote:
| Thanks for taking the time to sign up.
|
| I intend to use rockwool for the floor and roof crawl
| space.
|
| Luckily I have a relative in the field who can share
| advice. I am conscientious of the condensation issue.
| There's a company local to me who use hemp boards which
| are porous. What you say is definitely something to
| consider given the extent of work involved, and to
| possibly undo.
| markvdb wrote:
| Be super careful internally insulating an old house. This
| can cause _a lot_ of humidity problems if not done
| _exactly_ right. Very often, there is no way to do it
| exactly right!
|
| I would recommend you to consider breathable internal
| insulation materials, combined with breathable finish
| layers of course! Some hints.
|
| Roof (or attic floor) insulation is the most important. I
| imagine those have been done properly already.
|
| Walls. There's industrial products for walls, like Xella
| Multipor. You may also want to have a look at eco products,
| especially if working on the place yourself. Hempcrete is a
| fairly forgiving material that works rather well for this
| purpose. Rather expensive to have it installed, but easy to
| do yourself.
|
| Ground floors. Have a look at foam glass [0] insulation. It
| both stabilises and insulates, is moisture and fire proof,
| not horribly expensive and saves you from having to put in
| a layer of concrete. Not super well known yet, but growing
| in popularity. A wonderful material and super easy and
| forgiving to work with. A no-brainer really in many
| cases...
|
| [0] https://en.wikipedia.org/wiki/Foam_glass
| mnw21cam wrote:
| The one key rule that you should always follow is to have
| your water-impermeable layer on the warm side of the
| insulation.
|
| So, I'd recommend against breathable _internal_
| insulation, because that will make your solid wall
| (water-impermeable layer) colder, but still exposed to
| the humid inside air, and this could cause condensation
| on that cold wall. As an example of this, I have rubbish
| double glazing, and when the temperature drops outside,
| if I have just the curtains drawn (which don 't really
| provide any insulation) then I'm fine, but if I lower the
| thermal blackout blinds, then I get loads of condensation
| on the inside of the windows, which I remove with a
| window vac in the morning.
|
| Breathable _external_ insulation is less of a problem,
| because it warms up the wall, while exposing it to the
| comparatively dry air from outside, so you shouldn 't get
| any condensation.
| markvdb wrote:
| > The one key rule that you should always follow is to
| have your water-impermeable layer on the warm side of the
| insulation.
|
| This very much holds true in 99% of modern homes.. except
| if you build your entire wall breathable. That is how we
| did our walls. From inside to out:
|
| - breathable paint. Lots of conventional options
| available. We made a really nice casein paint with low
| fat cottage cheese and lime paint as the main ingredients
| :-)
|
| - lime plaster. 1/3 slaked lime powder, 2/3 sand.
|
| - 1.2m of straw
|
| - lime plaster
| HPsquared wrote:
| Agreed, houses with insulation have a vapour barrier
| behind the plasterboard for this reason:
| counterintuitively, the warm internal air carries a lot
| more moisture than the cold air outside. The partial
| pressure of water vapour is higher inside the house than
| outside, so the dew point of the internal air is higher
| than the outside temperature (dew point depends on water
| content).
|
| If there's a way for that moisture to diffuse through the
| wall from inside, through the insulation, to the cold
| structure (which would be colder than before due to the
| internal insulation), the conditions are right for
| condensation to form. Those conditions are: surface
| temperature <= dew point.
|
| Condensation can be prevented by a combination of:
|
| 1. Reduce the rate of moisture diffusion from the
| interior (seal the rooms and use a vapour barrier)
|
| 2. Lower the dew point of the air in the "cold"
| structural areas by ventilating the cold space to
| outside, so the moisture can exit (this is why houses
| have air bricks, vents in the roof, etc.)
|
| 3. Prevent the building structure from being colder than
| the internal dew point (i.e. use external insulation)
| lbriner wrote:
| An easier solution is plasterboard already bonded to PIR or
| XPS. The XPS is cheaper and I don't think it will make a
| massive difference depending on all the other challenges like
| windows and doors. You can simply stick this to existing
| walls with adhesive foam and then dry-line or skim the boards
| afterwards.
|
| To do it well, though, you will often need to cut out/remove
| any laminate flooring so the boards can meet the floor and
| they won't do anything about leakage between floors, which
| can be significant.
| KaiserPro wrote:
| > plasterboard already bonded to PIR
|
| As you point out they are normally ~25mm or so of EPS/XPS.
| which doesn't do _much_, especially compared to 600mm of
| stone. Plus XPS is pretty flammable, so with electricity
| cables sandwiched between it, its not a great thing to have
| inside the house.
| bainsfather wrote:
| I followed your link, but am confused and/or doubtful:
|
| how do you replace 150mm of rockwool with 20mm of anything
| other than a good vacuum? It says that they are 'very low
| internal pressure' - but if it contains any kind of gas
| (which i presume it must do - air if nothing else) then the
| conductivity does not depend on pressure until the mean-free-
| path has increased to be > the width of the container.
|
| Is this product real? What is it about the physics that I am
| not understanding?
|
| And how do you maintain the 'very low internal pressure' over
| the decades that you will need it for?
|
| Thanks.
| londons_explore wrote:
| > conductivity does not depend on pressure
|
| I think it might be fumed silica aerogel at about 0.1 bar.
|
| This paper describes the use of the same material for
| building insulation:
|
| https://www.researchgate.net/figure/a-The-thermal-
| conductivi...
|
| I suspect the key issue will be maintaining that low
| pressure for the ~100 year lifespan of the building.
| Perhaps future versions will come with micro pumps so that
| once per year the pressure can be pumped back down to 0.1
| bar. Looks like for about a dollar you can buy a little 3
| volt vacuum pump. One per panel out to do a decent job.
| coryrc wrote:
| It is a good vacuum. They work but are expensive and a
| single nail destroys the whole panel, but maybe cheaper
| than the loss of floor space.
| KaiserPro wrote:
| From what I've seen, its basically a honeycomb with a thick
| plastic coated foil to act as an atmospheric barrier. I
| came across it from a number of sites, but I've not managed
| to get any samples yet.
|
| > And how do you maintain the 'very low internal pressure'
| over the decades that you will need it for?
|
| now thats a million dollar question. I don't know.
| chipsa wrote:
| https://en.wikipedia.org/wiki/Vacuum_insulated_panel Looks
| like the thing. So, yeah, very good vacuum. It's apparently
| decades for the lifespan, but much of it boils down to the
| materials being used.
| dave333 wrote:
| They should also look at the Skytherm Roof which can both heat
| and cool a building passively. See
|
| https://www.architectmagazine.com/technology/harold-hay-skyt...
| CorrectHorseBat wrote:
| I don't see anything about heating a building?
| codefreakxff wrote:
| It's vaguely in the article. Says in the winter the process
| is reversed
| dhruval wrote:
| Reminds me of 'Earthship Houses' that are completely off grid,
| recycle their waste water to grow crops, are built using
| repurposed car tires and grow their own food.
|
| There is a community in New Mexico
| https://www.youtube.com/watch?v=wgUkjbMhF18
|
| And even some in Canada
| https://www.youtube.com/watch?v=EAvY5JeMz9w&t=62s
| goodpoint wrote:
| Earthship are very low density unfortunately.
|
| Good at reducing the environmental and economical impact of the
| house itself but now you have to drive a car instead of living
| car-free in a walkable city.
| dhruval wrote:
| Good point. I wonder what the environmental impact is of high
| density housing in cities vs low density (earth houses).
|
| I think it probably does make sense for rural communities.
| 35mm wrote:
| Yes! Any they typically make good use of passive + solar
| thermal management. For example automated window openings to
| draw heat through etc
| Cd00d wrote:
| Ha, I volunteered to build Earthships in New Mexico in 1995
| during my orientation week at college. Fascinating community.
|
| Thanks for the reminder.
| shlant wrote:
| that Earthship in Canada is owned by my best friends parents!
| It still get's pretty cold in the winter (Lethbridge winters
| are incredibly cold and windy) so it took some acclimatizing
| when they first moved in. I think they have improved it
| somewhat since then.
| masklinn wrote:
| Also reminiscent of a Canadian (?) advocate from the late 20th
| century, can't remember his name. Actually built a huge passive
| house with a large internal greenhouse and a small stream for
| air quality.
| johndhi wrote:
| Any tips for me? I live in Northern California in a house that
| (1) has an empty space below it, (2) single-pane windows, (3) an
| inefficient fireplace with no steel stove, (4) a big, cavernous
| room with high, un-insulated ceilings on one half of the house.
|
| Obviously we could spend a zillion dollars to insulate everything
| and fix all of the problems I identified above (and probably
| more), but what is critical?
|
| One thing we started with is putting a thermal curtain between
| the big, drafty room and the rest of the house so that the
| thermometer doesn't get triggered by the big room sucking the hot
| air out of the rest of the house.
| poseva wrote:
| 1. I would start by lowering the ceiling and insulating it. For
| ceiling if you insulate it using mineral wool, or glass wool...
| the vapor barrier [0] is critical and must be placed
| continuously on the warm part. Also this membrane (preferably
| containing aluminum so that you get back some of the heat) must
| be glued to the walls using special glue [1]
|
| 2. I would change the windows, with at least triple pane. The
| windows must be mounted correctly (see RAL montage) and also
| must be placed aligned with the outside face of the wall.
|
| 3. I would take out the floor, and do hydronic underfloor
| heating with EPS150 or XPS as insulation substrate.
|
| [0] https://www.rothoblaas.com/products/airtightness-and-
| waterpr...
|
| [1] https://www.rothoblaas.com/products/airtightness-and-
| waterpr...
| johndhi wrote:
| Thank you!
|
| what price do you think we're looking at for each of these?
| lowering the ceiling is a bit of a bummer from a looks
| perspective. underfloor heating sounds wonderful.
| poseva wrote:
| You're welcome! I live in Europe (Romania) and to be honest
| I would not know what to expect in terms of costs. You lose
| at least 25% of your energy trough the roof, this can even
| go up to 30-35% if the ceiling is cracked or air is able to
| circulate freely trough it.
| poseva wrote:
| I want to also to highlight the importance of the building
| airtightness (Air Changes per Hour) on the energy consumption
| needed for heating.
|
| I saw an example at some point in one of PassivHaus presentation
| and it was like this:
|
| 0.3 ACH -> 1.74 kWh/m2 _year (for a 100 sqm house means, 174 kwh
| per year for heating)
|
| 0.6 ACH -> 3.49 kWh/m2_year (PassivHaus limit)
|
| 1.0 ACH -> 5.81 kWh/m2 _year
|
| 1.5 ACH -> 8.72 kWh/m2_year (Low energy house limit)
|
| 4.5 ACH -> 26.5 kWh/m2*year (typical house)
|
| This is for the same house with the same insulation. Of course
| you cannot achieve this kind of airtightness without careful
| planning and using a lot of self-adhesive tape (SIGA, ROTHOBLASS
| and other manufactures that can guarantee its effectiveness up to
| 50 years)
| bythreads wrote:
| Checkout poroton, as a building material it is near impossible to
| beat - high insulation, low total cost, humidity seeps slowly
| thorugh the walls and termal mass is massive
| PinguTS wrote:
| In Austria an architect build an office building completely
| without any heating at all [1]. And now after the first
| experiences he is doing it for clients as well [2]. It works.
|
| [1] https://www.detail-online.com/article/house-without-
| heating-...
|
| [2] https://www.world-architects.com/en/baumschlager-eberle-
| arch...
| KaiserPro wrote:
| TLDR:
|
| point one:
|
| you need insulation _everywhere_, along with some thermal mass to
| make sure there is some inertia to keep temperature even. This
| means that putting a jacket around the outside of a brick/cement
| structure is generally better than putting it inside. You need to
| insulate under the floor.
|
| External wall insulation is not overly expensive. Its about 50%
| more expensive than a standard silicon render (in the UK)
|
| Point Two:
|
| Windows and doors are normally the weak spot. Standard double
| glazing has a U value of about 2. Depending on the coating and
| the position, they can also let in up to 2kw/m2 of heat through
| solar gain.
|
| You need ideally coated triple glazing, which if paired with the
| correct frames has a U value of about 0.8-1.1 The coating is to
| reflect solar gain. You will need sun shading so that in winter
| the sun comes streaming in, but in summer its shaded out by the
| small shades.
|
| In the UK its possible to get triple glazing at about the same
| price as double. For us, the big companies quoted >15k for shitty
| double glazing, local company was ~10k, eventual installation
| price was 8k for triple. This included custom arched door/window,
| and a french door.
| masklinn wrote:
| > Windows and doors are normally the weak spot. Standard double
| glazing has a U value of about 2. Depending on the coating and
| the position, they can also let in up to 2kw/m2 of heat through
| solar gain.
|
| Also do be careful of thermal bridges and missing seals at and
| around the frame.
|
| My current rental is relatively well insulated all in all,
| _but_ one of the huge weakpoints is the stone sill of one of
| the east-facing windows, I don't know what the builders fucked
| up but in winter it can literally serve as a fridge.
| alkonaut wrote:
| > Standard double glazing
|
| How is the code still allowing new construction with windows
| having U of 2 (such as double glazing)? A more restrictive code
| would reduce a country's CO2 footprint, companies would sell
| more expensive products like windows, and no one except the few
| constructing new homes would be economically impacted - and
| obviously only short term, while the economic gains are reaped
| by everyone. So how is this not politically easy to just...do?
| Mvandenbergh wrote:
| Effectively it isn't allowed since the whole building has to
| meet a minimum efficiency standard which would be impossible
| to meet with U=2 windows throughout.
|
| My double glazed windows have a U value of 1.2 and typical
| for triple is 0.8 so the improvement isn't that big between
| good new double glazed and triple.
| KaiserPro wrote:
| > How is the code still allowing new construction with
| windows having U of 2 (such as double glazing)
|
| its complex. but as I'm retrofitting the rules are different.
| The standards are here: https://great-home.co.uk/building-
| regulations-current-u-valu...
|
| But the real kicker is that glazing should have bleeder vents
| in them, in some circumstances. Which is a pain in the arse.
| Most of my windows don't have them, but the two in the loft
| extension do.
| alkonaut wrote:
| Yeah having different rules for retrofitting is
| understandable (Although it would be good if those who
| retrofit were at least required to improve the status quo
| of the building, if not required to bring up to the
| standard of new building).
|
| But what blocks the code from saying e.g. U=1.2 for new
| construction which is a normal (and honestly pretty cheap)
| triple glass window?
| locallost wrote:
| I watched a report on a block of "passive houses" in Germany and
| the people liked it, but had a complaint that the air is too dry,
| so they dried their laundry indoors. I'm a fan of the idea, so
| not really critical, but I wonder what it's really like to live
| in one.
| orthoxerox wrote:
| Yes, the ventilation system inside a passive house needs not
| only a heat exchanger, but a humidifier as well. Actually, I'd
| rather dry my laundry to humidify the room than rely on a
| humidifier that can grow bacteria and mold inside.
| Cthulhu_ wrote:
| > [...] than rely on a humidifier that can grow bacteria and
| mold inside.
|
| That's down to maintenance and care; change the filters and
| clean it regularly. Like everything else in your house. You
| need to change and maintain filters in a heat exchanger as
| well.
| gambiting wrote:
| >>than rely on a humidifier that can grow bacteria and mold
| inside.
|
| There are humidifiers with UV-C lamps inside that sterilize
| themselves as they run. Dyson makes some, but I've seen them
| from other brands too.
| dredmorbius wrote:
| Indoor plants are also useful in this regard, as the plants
| (and their containers) will return humidity to the air.
| poseva wrote:
| Instead of a heat recovery ventilation you can use energy
| recovery ventilation which gets back some of the humidity,
| otherwise just buy a cheap electric boiling humidifier and it
| you get the job done. What is important that in the coldest
| part of the winter you can turn down the ventilation to a
| minimal, something like 0.3 hourly exchanges per hour.
| KaiserPro wrote:
| > winter you can turn down the ventilation to a minimal
|
| The problem is that the Heat exchanger actively draws
| moisture out, as it has a huge cold surface area that forces
| water out of the air. If you don't change the air it feels
| stuffy.
| netjiro wrote:
| You can buy heat exchangers with very high efficiency and
| good moisture reclamation or suppression for a slightly
| higher cost. The problem is usually that the customer does
| not look into the details and the construction company can
| increase profits by buying cheaper versions.
|
| A good modern ventilation energy exchange unit for a 300m2
| house can be <30dB, >90% efficiency, and return a lot of
| humidity.
| chippytea wrote:
| Modern heat exchangers allow you to set the air humidity.
| dahfizz wrote:
| > Even in places known for their extreme weather conditions -
| such as 'hot 'n' cold' Otago, wind-prone Wellington and sweaty
| Auckland - high-performance homes will stay comfortable and fresh
| all the year round.
|
| All these places stay above 45F and below 80F. This is anything
| but extreme weather. You don't need any sort of special "high
| performance" house for this kind of temperate climate.
| blackearl wrote:
| Living in a true hot n cold New England USA makes me jealous
| that anyone would consider this extreme. It's sweater n t-shirt
| weather. I consider hot n cold being 100F in the summer and 0F
| in the winter.
| roamerz wrote:
| In Oregon the new building code mandates that all air ducts and
| air handlers be located in conditioned space. Really good common
| sense regulation imho.
| lbriner wrote:
| I think this is one of those things where people generally agree
| that better insulation and lower energy costs is a good thing but
| who pays for it?
|
| In the UK, there is a constant demand for "affordable housing",
| which is caused by governments not controlling the housing market
| from either foreign investors or also people using the housing
| bubble to buy up loads of properties over time forcing others to
| rent.
|
| Bearing in mind how much profit a lot of home builders make,
| increasing the regulations is likely to add at least PS20K to a
| basic house, significantly more if you include mechanical
| ventilation, triple-glazed windows and heat pumps (perhaps
| +PS50K), which is some cases will be 50%+ of the original cost!
|
| Another major problem is the quality of building in the UK,
| mainly driven by a lack of tradespeople, and simply not having
| the skills to install to the quality levels required by thermally
| efficient houses like installing a membrane with zero holes in
| it, using the correct tapes, designing, installing and
| maintaining heat pumpes and various other things.
|
| I think these challenges will get better over time but that is
| probably why governments aren't keen to make large improvements
| in energy-efficiency regulations.
| thebiss wrote:
| > Another major problem is the quality of building in the UK,
| mainly driven by a lack of tradespeople, and simply not having
| the skills to install to the quality levels required by
| thermally efficient houses like installing a membrane with zero
| holes in it, using the correct tapes, designing, installing and
| maintaining heat pumpes and various other things.
|
| It's an incentive and delegation problem. I'm in the US, and
| have been through three large renovations to family homes, and
| the trades I've worked were (nearly) all HIGHLY skilled, but
| had zero incentive to exceed energy efficiency goals required
| by code. The small business contractor needs to complete your
| project, get paid, and move on to the next. The best ones don't
| have any extra time - they're prospecting clients and building
| estimates for the next big project.
| jayflux wrote:
| > Another major problem is the quality of building in the UK,
| mainly driven by a lack of tradespeople, and simply not having
| the skills to install to the quality levels required by
| thermally efficient houses like installing a membrane with zero
| holes in it, using the correct tapes, designing, installing and
| maintaining heat pumpes and various other things.
|
| I agree with the sibling comment this is an incentive problem
| rather than a skill problem. If house builders can cut corners
| they will. If they can sell a house for the same cost without
| the fancy new insulation gear they will.
|
| This is why your bit about regulation is needed because
| otherwise the things you list won't happen. Home chargers are a
| good example which the govt deemed necessary for new builds,
| the skill will be there for that and without the regulation I'm
| not sure most builders would have bothered, leaving people to
| retrofit one further down the line paying a higher cost. The
| skills for heat pumps will organically grow as regulation kicks
| in too.
|
| > why governments aren't keen to make large improvements in
| energy-efficiency regulations.
|
| The govt have been consulting with various business and
| institutions on future building standards you can view their
| response here: https://www.gov.uk/government/consultations/the-
| future-build.... But from it we've already had EV charging
| point requirements, ban on gas boilers, new homes in England
| will have to produce around 30% less carbon emissions, plus
| raising the standard for insulation.
| bogle wrote:
| > I think these challenges will get better over time but that
| is probably why governments aren't keen to make large
| improvements in energy-efficiency regulations.
|
| This is probably true but it's still backwards. The state
| should want to improve the affordability of housing and should
| consult with industry on which measures can be introduced but
| ultimately the state must introduce the new regulations to help
| drive the market in the direction of continuous improvements to
| the housing stock's long-term affordability. I think if they
| shirk this then they simply aren't doing the job properly.
| Mvandenbergh wrote:
| >Bearing in mind how much profit a lot of home builders make,
| increasing the regulations is likely to add at least PS20K to a
| basic house, significantly more if you include mechanical
| ventilation, triple-glazed windows and heat pumps (perhaps
| +PS50K), which is some cases will be 50%+ of the original cost!
|
| The sales price of houses in the UK (and elsewhere) is driven
| by the market and there is a low amount of released, buildable
| land and a lot of demand in the Southeast. The land value (a
| large component of the value) is not actually set in an
| independent market but is based on the expected sales price
| minus construction costs and development costs. Therefore
| increasing the built cost of properties will decrease the value
| of land likely to receive planning permission without affecting
| purchase price by much.
|
| The marginal cost of thicker walls is also very low (especially
| compared to retrofit costs) so the impact on construction cost
| is nothing like PS50k.
| nikanj wrote:
| The English have been building homes with virtually no heating
| since forever
| jwr wrote:
| While this is at the extreme end of the spectrum, there is a much
| easier way to save lots of energy: just build modern well-
| insulated homes.
|
| I lived in California and I was appalled at the monstrous energy
| waste: houses are generally made pretty much from cardboard. You
| need to cool them in summertime and heat them in wintertime, and
| the energy expenditure is enormous.
|
| I now live in Poland and have recently built small homes that are
| similar in structure to the ones in CA: wooden frame, drywall
| inside. But the ones here have walls that are 25cm thick because
| of insulation (mineral wool) and use advanced modern membranes as
| well. Together, these things do wonders, and maintaining warmth
| in wintertime using a heat pump (AC) is easy and doesn't cost an
| arm and a leg.
|
| In other words, you can get 80% of the benefits with 20% of the
| effort -- just design thicker walls with insulation and use
| modern materials.
| raxxorrax wrote:
| I even prefer this to a complete passive house. To be honest I
| don't like the air from ventilation, although that probably
| depends on the system.
| hansvm wrote:
| Echoing the sentiment, it cost significantly more for me to
| heat a studio to 65F in CA than to get a 2/1 up to 72F in ND
| (or rather, to maintain those temperatures).
|
| Both units had electric baseboard heat and were top floor
| apartments, but the CA unit didn't have double pane windows,
| had enormous gaps at the doors and windows, and for all intents
| and purposes didn't have any insulation. If it was warmer than
| 0F or so outside the ND unit would have more than enough heat
| just from cooking. If it was colder than 50F or so the CA unit
| needed the heaters to actually be on.
| danans wrote:
| >I lived in California and I was appalled at the monstrous
| energy waste: houses are generally made pretty much from
| cardboard. You need to cool them in summertime and heat them in
| wintertime,
|
| This is the legacy of historical low energy prices coupled with
| a historically mild climate.
|
| Now, both of those things are changing. Energy prices are
| rising because of global warming accelerated risks, and
| simultaneously the climate is getting hotter and dryer.
|
| The result is that it can start making sense to build to a
| higher standard like passive house in CA - I just did and my
| HVAC energy usage dropped 75% and is now more comfortable.
|
| However, there needs to be better code enforcement - i.e. air
| leakage for new homes should be closer to 2.0 ACH50, not the
| totally unenforced 5.0 ACH50 on the books today - and also
| better education of buyers so they can start demanding better
| built and more efficient homes.
| bogle wrote:
| "About the only part of a Californian house you can't put your
| foot through is the front door." 'The Big Sleep', Raymond
| Chandler (1939).
|
| Good to see nothing's changed!
| jwr wrote:
| Oh, this is so very true! In addition, said front door is
| protected by a flimsy deadbolt that sits in a dinky thin door
| frame. The whole thing breaks and opens with a kick and
| offers symbolic, rather than practical protection.
| [deleted]
| hyperbovine wrote:
| Of course nothing has changed, he's talking about the exact
| same housing stock.
| closeparen wrote:
| Coming from a decidedly unsexy post-industrial Midwestern city,
| I was very surprised to learn that for all the wealth and
| splendor of California, most of the buildings here seem
| horribly impoverished.
| jve wrote:
| Don't forget to mention that insulating roof is just as
| important. Otherwise, heat will happily escape over your head.
| jwr wrote:
| Yes, I wasn't stating the obvious: you need to insulate the
| floor and roof as well. For example, reinforced concrete
| foundation slabs are usually placed over XPS foam boards
| here. There are many ways to do this, my point was that you
| don't have to go to extremes to get impressive benefits of
| modern insulation.
| ZeroGravitas wrote:
| They mention that they avoid over sealing, for local climate
| reasons but an interesting technique/gadget for sealing the air
| barrier is to vapourize some caulk type stuff in the air and
| force air in through a fan. As the air escapes through small
| holes it fills them.
|
| Apparently without this you need to be very careful while
| building, while this lets you go a little faster and sort it out
| after.
|
| https://www.finehomebuilding.com/2013/05/15/a-shortcut-for-a...
|
| There's also a recent development where just slapping on some
| solar panels can sometimes make more sense than extra insulation,
| in terms of cost and return.
| squigg wrote:
| I met the founder(s) of ArchiPro at a cloud event in Wellington
| in either 2013 or 2014 - it is wonderful to see their idea not
| only be sustained but thrive, bravo!
| Acen wrote:
| Milot and Britt's vision for having an impact on the building
| industry is going to take a lot of work, but they're one of the
| few people that seem to have unlimited drive for it. - I worked
| as a dev for ArchiPro from March 20 - December 21
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