The brick arches generally employed in small buildings are flat, segmental, or full semi-circular (Figs. 25-29). The segmental and semi-circular arches are usually best built of rowlock courses, their number depending upon the width of the opening. Flat brick arches over two feet wide should be supported by steel, the brick being usually set soldier fashion. As these brick are slightly inclined from the vertical, their end edges should be clipped to make the joints on the face of the arch come in a horizontal line, as in Fig. 26. In Fig. 25, the appearance of the arch face is not so workmanlike and neat because the brick have not been clipped along the line of the middle joints. For either type of arch, the brickwork both sides of the opening must be beveled in the form of skewbacks, to serve as beds for receiving the thrust of the arch as shown in the figures. If these arches are properly handled both as to design and execution, they add greatly to the appearance of the entire wall surface.
Various Methods of Furring
The inside of all exterior brick walls should be furred, except in climatic conditions where it has proved unnecessary, in order to form an air space between the brickwork and the plaster. This furring may be of wood, hollow tile, or metal. WoodThe first, which is ordinarily used, consists of 1" × 2" wooden strips placed vertically on the wall and spaced 16 inches on center (Fig. 24). The strips are either nailed to the lath which have been placed in the joints of the brickwork by the mason, or attached by driving the nails into the mortar joints. The carpenter, in placing the strips, should wedge behind them where necessary to make them plumb. The grounds and lath are placed directly on these strips. Hollow Tile Hollow tile furring is formed by splitting 3-inch or 4-inch "split furring" tile, which have been scored in manufacturing for this purpose, placing the webs against the brick wall, and anchoring them by driving ten-penny nails into the mortar joints over every third tile in every second course. The tile should be laid without mortar so as not to make a solid connection which would transmit moisture. This tile furring makes a good surface for interior plastering. MetalMetal furring is only used with metal lath and consists of small steel rods or other stiffening members either placed separately on the wall or as part of the metal lath.
Cleaning and Pointing
Not until after the plasterer has left the job should the face brick be cleaned or washed down. This is done with a 5 per cent muriatic acid solution or about one pint of acid to four gallons of water. A stronger solution is likely to do injury. Apply with a good scrubbing brush to remove all dirt and spattered mortar, and then rinse with clean water. While washing the wall, defects in joints should be pointed up.
The Hollow Brick Wall
A variation of solid brick construction is the so-called hollow or vaulted wall in which the face and common brick are separated by a two-inch air space and bonded together by metal ties laid in the mortar joints at proper intervals. This type of wall has been extensively used for many years, especially in the East.
Its friends claim that it is stiffer than a solid wall of the same amount of brick; that it offers a better insulation, by reason of the air space, against cold and dampness; and that therefore it saves the necessity of furring and fire stops on the interior wall surface. On the other hand, admitting the value of the air space and the consequent saving of furring, objection is made that the air space is apt to get filled with mortar and brick chips during construction; that the metal ties, unless heavily galvanized or dipped in asphaltum, rust out in a comparatively short time; and that it is not as strong a bearing wall as the solid wall of the same brick content. Mr. Arthur W. Joslin, a contractor and builder of Boston, whose extensive practice gives his judgment weight, says in summing up the pros and cons: "The 10-inch vaulted wall is strong enough for ordinary dwellings, even though the ties do rust out, unless it is built out of the poorest kind of brick with very poor mortar. In my opinion, a vaulted wall, if properly built, the vault not filled up with droppings, and provisions made for ventilating from the inside, is an ideal wall for dwelling house construction, but I would not recommend it for buildings for other purposes where there would be more or less of a dead load coming on the floors." On the matter of comparative costs, Mr. Joslin adds: "It is cheaper to build an 8-inch solid than a 10-inch vaulted wall, and slightly cheaper to build a 10-inch vaulted than a 12-inch solid wall."
The accompanying drawing shows a cross section of this type of brick wall. Except in a few particulars, its construction does not differ essentially from that of the solid brick wall as already described.
A 12-inch brick foundation is wide enough for the 10-inch wall and a 16-inch foundation for the 14-inch wall. The metal ties, heavily galvanized or coated with asphaltum, should be placed about 18 inches apart at every fifth or sixth course and extend at least 2 inches into the mortar joints.
Fire stops are not needed, nor is furring, as the plaster may be laid directly on the brick. In order to preserve the chief merit of this type of brick wall, great care should be taken, during construction, that the 2-inch air space be not allowed to fill up with mortar and brick chips.
The local ordinances in some municipalities require thicker walls with hollow tile construction than where common brick backing is used, which affects the comparative cost of the buildings; but, where the total thickness may be kept the same as for solid brick, the cost is practically the same, with slight differences one way or the other in different communities. The tile used for backing may be either soft or hard burned, but never with an absorption of over 12 per cent, and are scored variously so that there may always be a good keying surface for plaster. These tile may be set with the hollow spaces or cells running either horizontally or vertically, as the case demands or the builder chooses.
Walls of this form of construction are built in much the same manner as walls with common brick backing, except that it is always desirable to use cement mortar with the tile to insure the needed strength of bond. The face brick are first carried up four or five courses and then the hollow tile units, of whatever thickness chosen, are laid up behind the brick, leaving an inch space between the tile and brick (Fig. 31). The tile are laid, with broken joint as in running bond, in a half-inch mortar bed. When the tile width is over 4 inches, the mortar should be spread only on the front and back edges of the tile, leaving a hollow space in the center. In the vertical joints only the front and back webs require mortar. If vertical tile are used all the webs should be well mortared, while the vertical joints are simply buttered.
Care must be taken that the space between the tile and brick does not get filled up with mortar, for this would defeat its purpose of serving as an insulation against moisture and cold. With this one-inch space between brick and tile open, furring and lathing are saved, as the plaster may be directly laid on the tile and the necessity of fire stops avoided.
At window and door openings, in case 4" × 5" × 12" or 8" × 5" × 12" horizontal tile are laid, either common brick or special half and full closure tile (Figs. 31 and 59) should be used, in order to close the openings at the end of the horizontal tile courses, thus making around the frames good joints which should be tightly filled with mortar. When the 12" × 12" tile are laid horizontal, those in the window and door jambs need simply be set vertical to serve as closures.
It will be found that an even number of tile does not always work out with the length of the wall or pier, leaving a space of a few inches. This space may be filled by cutting a tile or using pieces of tile slabs.
For houses of the character presented in this Manual, tile either 4, 6, or 8 inches wide may be used, depending on local ordinance or the choice of the owner. A 5-inch backing may be obtained by simply laying the 4" × 5" × 12" tile on the 5-inch edge. Both 4- and 8-inch widths are made 5" × 12" or 12" × 12" in height and length. The 6-inch width generally comes 12" × 12" in height and length, but may be obtained in the 5" × 12" size from certain manufacturers, if so desired.
The 5" × 12" tile in either width are laid horizontal, while the 12" × 12" tile in either width may be laid vertical or horizontal. Either method is satisfactory although, for heavy bearing walls, some builders prefer the vertical method on the ground that it gives a stronger bearing wall because the vertical webs directly bear on each other. If laid vertical, the top course of tile should be placed horizontal to give a good bed for the wall plate.
Four courses of standard size brick, provided a 3/8-inch mortar joint is used, will equal in height two 5" × 12" tile, making every fifth course a bonding course (Fig. 31). And five courses of standard size brick, provided a 1/4-inch mortar joint is used, will equal in height one 12" × 12" tile, or if 1/2-inch joints are used, will equal in height 3 courses of 4" × 12" tile 5 inches wide, making every sixth course a bonding course. If wider mortar joints are desired, you can in the latter case make every fifth course a bonding course by using 12" × 12" vertical tile which you can order cut to any length required. But where either the 5" × 12" or the 12" × 12" tile are laid horizontal, the number of courses of face brick and the size of mortar joints cannot be changed.
The face brick are bonded to the tile backing (Fig. 31) precisely in the same manner as previously explained for common brick, double headers being used in case of Stretcher Bond and the headers, wherever required, in other bonds (See page 18). But as this wall is full 9 inches or more thick, the headers in the bonding courses leave recesses one inch or more deep at intervals on the inside face of the wall (Fig. 31). These if shallow, should be filled with plaster, containing a large amount of fibre, before the regular plastering is started; if deep, as when the 8-inch wide tile is used for backing, a stretcher course of common brick or brick-size hollow tile fills the space.
The chimney construction does not differ in any essential from that used for the solid brick wall, but we strongly urge the use of brick for the chimney, rather than tile or concrete blocks, as affording more reliable protection for the flue.
The window sills, door sills, and lintels are the same as in solid brick construction except that, preferably, instead of the wooden lintel supporting the backing, the lintel be made of hollow tile filled with cement and reinforced by one or more steel rods (Fig. 32). These tile lintels should be made on the ground by standing the tile on end for filling. When the concrete is set, they are ready to be lifted into place.
The story heights should be figured so that an exact number of whole tile may be used from the bottom of the joists on one floor to the bottom of those on the next floor, always allowing one-half inch for the bed joints. But where this is not possible, special tile slabs one inch thick, which may be had from the dealer, should be used to obtain the exact height required, so that an even and solid bearing may be formed for the floor joists. The wall plates for the roof construction are anchored in the same manner as in the solid brick wall, except that anchors should be 20 inches long; likewise, brick nogging should be placed between the roof rafters.
As in the case of the solid brick construction, when the plasterers have gone, the face brick should be cleaned down and pointed where necessary.
As already indicated, this type of wall construction is preferred by some builders because it is somewhat less expensive than solid brick or hollow tile and can be more quickly built. The wooden frame may be completed and roofed before the brick veneer is started on the outside. If constructed according to our specifications, the veneered wall makes a much warmer and more comfortable house than frame, not only because the veneer wall is over 2 inches thicker than the frame, but because the brick veneering forms a solid monolithic shell that steadies the framework and is proof against the wind pressure that searches out the cracks and crannies of the less substantial construction. Furthermore, while the veneer house does not get the favored insurance rates of the solid brick structure, it is, if provided with a non-combustible roof, safe against adjacent fires; in fact, from the exterior, presents the advantages of a solid face brick house.
In this type of construction the studding is not placed at the face of the foundation wall, but set at the back of the wall, allowing sufficient space in front of the sheathing for the veneer of face brick. The studs are then sheathed as for the usual frame building and covered with building paper, held in place with 2" × 1" or 1" × 5/8" furring strips, laid on vertically or horizontally over each lap of paper and once between. The face brick, set one inch from the sheathing, are laid up, so far as the outer bond is concerned, in the same manner as for facing the solid masonry wall, and are fastened to the framework by metal ties spaced horizontally about on every stud and vertically every four or five courses (Fig. 33).
These ties are of two kinds, either corrugated metal strips with one end nailed to the sheathing and the other laid in the bed joints, or thirty-penny wire nails which must be spaced with the studs into which they are driven through the sheathing, so as to leave a projection sufficient to extend about one inch into the bed joints of the brickwork.
The last method is recommended as the most substantial and permanent, but care should be taken that the nails be driven with a slant into the wood frame at a point somewhat above the brick so that when tapped by a hammer they may be bent down to the level of the joint (Fig. 34). If they are driven in at the exact level of the brick, they will, when bent down, push the brick out of alignment.
Brick window sills with this type of construction are the same as for the solid masonry wall, except that the inner ends of the brick must be cut to fit against the sheathing. The window and door frames are set in place as in frame construction. While the brickwork over openings may be carried on arches, steel angles are almost universally used for this purpose.
The brick porches should have the porch walls and piers of solid brickwork faced on both sides, with bond pattern or ornamentation following, in the main, the design of the house walls.
Chimney construction for the veneer house is the same as for the brick house, except that care should be taken in setting outside chimneys clear of the sheathing, so as not to cut into the frame construction.
Veneering Old Frame Structures
It often occurs that a frame house is not kept in repair and depreciates to such an extent that the expenditure for necessary painting and repairs to restore it would amount to an unwarranted figure. Or, as in many cases, the frame house, though kept in fair condition by dint of frequent painting and repairs, is decidedly out of date, or lacks the "class" that surrounding buildings may have. This often applies also to the old spotted and stained stucco house. In either case, the owner suffers loss in the value of his investment. There is a simple way, however, to recover this loss and more than restore the value of his investment, and that is by veneering the house with an attractive face brick. The framing of the house is in all probability substantially sound, it is only the exterior that is dilapidated and outclassed. By veneering his house with a well-chosen face brick, laid in proper bond and mortar joint, the owner at a comparatively small expenditure has got what is to all intents and purposes a new house.
In the first place, he has "painted" it once and for all with beautiful colors that will never come off, and he has eliminated all future paint and repair bills for the exterior where much of his cost of upkeep for the old frame house came. In the second place, he has a far more uniformly comfortable house with a very appreciable reduction of his coal bills, due to the solid, monolithic shell of brick covering the frame. Practical heating engineers engaged in installing heating apparatus calculate that in a moderate sized veneer house as compared with frame there is, during an average winter in the North, a saving of approximately 8 per cent on the coal bill.
Finally, he would have, so far as the community is concerned, or a possible future purchaser, an attractive modern face brick house, of which he may be proud as a place of residence, or which would be more profitable as a renting or selling property. The enhanced value of his property would be far beyond his expenditure.
Many contractors could comfortably increase their profits and keep busy through dull months by presenting the above facts to the owner whose old frame or stucco house needs repairs. Instead of giving him a staggering figure for repair work that is only temporary, he could be shown how, by investing a little more, he could greatly contribute to his personal satisfaction and substantially increase the value of his property. Veneering an old house, either frame or stucco, is no more difficult than veneering a new structure and is accomplished in much the same manner.
An eight-inch concrete footing should be placed against the outside of the existing foundation wall, extending from grade to below frost line and resting on good solid soil. The brick veneer, starting from this footing, is carried up with an inch air space between it and the old siding (which is not removed) and tied by driving thirty-penny nails through the siding or other finish into the sheathing and studs (Fig. 35).
The usual steel lintels are used over window and door openings. Where the veneer is to be carried over porches or other low additions, the siding immediately above the roof should be removed and a steel angle placed against the sheathing and securely attached to the studs by lag screws, so that no weight of the brickwork comes on the roof. See illustrations of work on page 16.
The brickwork is laid up to the door and window trim and a staff bead molding, in the corner formed by the brick, securely nailed to the old trim, making a tight joint (See Fig. 35). Similar mouldings should be placed at the underside of roofs, porch ceilings, and like places where the brick meets the old frame finish.
New Store Fronts
A very remunerative addition to his business may be made by the builder in veneering old frame or stucco store buildings. All that applies to the advantage of veneering the old frame house especially applies here. An attractive store front is one of the merchant's best advertisements. It indicates that he is prosperous, and it draws customers who always prefer to deal with the successful merchant, and where the surroundings are pleasant. Show the merchant of your town the increased value of his property and the increased profits of his business made possible by a beautiful store front of face brick, and you will get more business yourself.
A New Face Brick Porch
Sometimes the porch on a frame building is in need of a new floor, railing, and steps. Instead of rebuilding the frame porch which will need constant repair and painting, a new face brick porch with either a brick or wooden floor could be built which would not only end all repair bills but vastly improve the appearance of the house. This may be accomplished very easily. Remove the entire porch except the roof which should be held by temporary supports. After excavating to the necessary depth, build a common brick foundation to grade for the piers and wall of the porch. The piers should be the same dimensions as the brick piers above, and the connecting wall should be 8 inches thick. Above the grade this 8-inch wall should be finished with face brick on the outside, while above the porch floor it should be face brick on both sides; and, at the correct height, should have a coping of face brick laid on edge. The piers should be carried up to the porch cornice and may be finished with a course of brick on edge, projecting slightly, to match the coping on the porch wall, or in any other plain or ornamental fashion desired. Where the walls join the frame building they should be anchored with nails driven into the wall the same as already explained for brick veneer work.
While the cost of a new brick porch on an old house is moderate, it adds greatly to the appearance of the house and thus appreciably increases its market value.
The Glow of the Friendly Hearth
It is the dream of most people when planning a home to have a real fireplace in which they may have a real fire of real logs, around which to sit with family or friends during the long winter evenings. Every home, even one built of frame or stucco, should be provided with at least one real fireplace.
And no matter what kind of a house a man may build, he won't find anything else quite so good or appropriate for a fireplace as brick. For having stood the test of flame in their making, they defy the flame in their use. The feeling that the roaring fire on the hearth beats harmlessly against the enduring brick, as the sea beats in vain against a granite headland, gives a genuine sense of security and satisfaction. Then the texture and color of the brick make them at once adaptable to any type of room or scheme of interior decoration the lady of the house may choose.
The location of the fireplace in the room is of great importance to its enjoyment. As it is the most ornamental feature of the interior of the house, it should be given a prominent position, but it should not be in the line of travel through the room, near the entrance door, or where a cross draft sweeps it. The far end of the room is one of the best locations; or better still, an ingle nook. If placed on the broad side of a room, it is pretty sure to project so far as to reduce the practicable width of-the room and force the rug over the hearth. If placed on an outside wall, it is best not to have large flanking windows, as one does not like to sit facing too much light, especially where a strong sun is shining.
Proper proportions of the fireplace opening and flue are among the most essential features of fireplace construction. The larger the opening, the larger the fire may be and the more air required or taken from the room for proper combustion, provided the flue is large enough to give sufficient draft. In the average home, the actual inside area of flue should never be less than one-tenth of the area of the fireplace opening. Each fireplace should have its own individual flue carried full size to the top of the chimney without connections of any kind from other sources. A low, broad opening is preferred to a narrow, high one, and splayed sides are best in any case, because better draft and radiation are thus secured. A low, broad opening will catch the smoke better and direct it up the chimney.
The following dimensions for fireplaces are considered good practice:
Fireplace Openings
| Width | Height | Depth |
| 2'-8" | 2'-4" | 17" to 21" |
| 3'-0" | 2'-4" to 6" | 21" |
| 4'-0" | 2'-8" | 21" to 25" |
Arched openings may be higher than indicated in the above dimensions, as their average height may be taken as the top line of the opening.
The ideal form of a fireplace would be a cone with all sides tapering to the apex for the escape of smoke. Therefore, to approach this ideal in practice, the sides of the fireplace are splayed and the back curved forward as shown in Figs. 36 and 37. This forward curve of the back throws the smoke from the fire forward to a throat 4 inches wide, extending the full width of the opening at the front and top of the fireplace, and at the same time forms a shelf above for the deflection of down drafts in the chimney. The rear wall of the fireplace should never be straight, having the throat at the rear, as down drafts would be sure to blow smoke and dust into the room.
Always place a damper in the throat for regulation of the draft. The damper should completely fill the throat. There are many dampers on the market that also serve the purpose of a lintel for the brickwork, giving a smooth surface for the exit of the smoke. These patent combinations of damper and throat give a good draft, prevent smoke, and deserve a more general use.
Especial care should be taken in laying up the brickwork above and around the damper. The joints should be well filled, and nowhere should there be less than an 8-inch thickness of brickwork unless protected by the flue lining.
Immediately above the damper, the brickwork should be corbeled in both ways to the size of the flue lining, which should always be started on a line with the middle of the fireplace and run vertically for one length. It then may be jogged over to the location desired on the floor above. It should be started as low as possible as this is the hottest part of the chimney.
The back and sides of the fireplace, as well as the back portion of the hearth are usually built of fire brick. Certain kinds of face brick are suitable for this purpose and have been used by architects with very artistic results.
The hearth may be either of face brick or tile. If of brick, they should be preferably smooth so as to facilitate cleaning. They may be laid either on edge or flat in a variety of patterns. Two examples of brick hearths are shown in Figs. 38 and 39, one with the brick set on edge and the other with the brick laid flat. Tiles may be of any size and laid in various patterns, and if suitable, may be used also in the back portion of small hearths. The mortar joints of the hearth should be thin and preferably of a fire clay mortar, though pure cement mortar will answer the purpose. Wherever possible, an opening and ash chute in the back hearth, with a pit and iron cleanout door in the basement, should be installed.
Always build the fireplace in the rough first, leaving the brick facing and hearth to be finished after the plasterer has completed his work. The accompanying designs, A, B, and C, suggest various methods of treatment.
Outside Ornamental Features
The possibilities of the use of brick for floors, walks, steps, pergolas, gate posts, seats, and other places about the house and garden are unlimited. For outside work it is a most permanent and beautiful material which never cracks or decays requiring periodic repairs or painting such as other materials do. It may always be the same color and texture as the brickwork of the house, thereby linking the house and garden together into one harmonious whole.
Brick steps, except where supported by the foundation wall, as shown in our working drawings, should always be laid over a concrete slab, reinforced, unless resting on solid, undisturbed soil. The concrete slab is poured in the form of steps, to correspond to the finished brick steps, but with proper allowance for laying the brick flat or on edge in a cushion of sand, at the option of the owner. Figs. 40-42 illustrate different pitches of steps and methods of setting the brick. Great care should be taken in the laying of brick steps, if they have to withstand severe usage. The joints should all be filled with a rich cement mortar composed of one part cement to two parts sand.
Fig. 40. Steps with End-set Treads |
Fig. 41. Steps with Flat-set Treads |
Fig. 42. Steps with Edge-set Treads |
Brick walks and floors, with the brick on edge or flat, are usually laid on a filling of cinders or sand, but if subjected to hard use, they should be placed on a bed of concrete the same as steps. Two favorite patterns of edge set brick are shown in Figs. 55 and 56. The brick may be laid flat in the same patterns, but the effect is not quite so pleasing. The joints in the brick walk or floor are usually filled with sand, swept into place with a broom so as thoroughly to fill the joints, but they may be filled with cement grouting if desired. The thin grouting is carefully poured into the joints after the brick are laid, and all grouting that spills on the surface of the brick cleaned off before it hardens. The borders of the walk or floor may be made of brick set on edge or on end; or, if preferred, of concrete, especially when the walk or floor is placed on concrete. If it is desired to prevent grass and moss from growing in sanded joints, mix salt with the sand before filling the joints.
For pergola posts, brick imparts a feeling of strength and solidity, yet care must be taken not to make the posts too large, as they will be entirely out of fit proportion to the light wooden rafters and vines which they support. In most cases, a post 12 inches square will be about the right size. Foundations for these posts should always extend below the frost line and be of brick or concrete. A long, one half inch steel rod with nuts and large washers at each end should be imbedded about 18 inches in this foundation and extend beyond the top of the finished post. The brickwork of the post above grade should be one brick thick, laid in cement or cement-lime mortar giving a hollow space 4 inches square in the center of the 12-inch post. As the work progresses this space is filled with concrete around the rod, which, passing through the center, binds the brickwork together in a solid, reinforced mass (Fig. 43). The cap of the post may be either brick, stone, or concrete placed when filling the interior. The wooden girders of the pergola may now be bolted to the post by means of the bolt projecting above the top.
If conditions or design demand a heavier post than 12 inches square, as in Fig. 44, no steel rod reinforcing will be necessary for stability.
Gate posts are usually lower and heavier than pergola posts and made stable enough to carry whatever weight the iron or wooden gate may demand. Large driveway gates (Fig. 45) should have a steel I-beam or angle placed in the center of the post and extending from the bottom of the foundation to the top of the post. The anchors for the support of the gates should be riveted to this steel beam or angle so that no undue strain will be exerted on the brickwork. The brickwork should always be laid in cement or cement-lime mortar. If ornamental caps are desired, they should be of stone or concrete. On large posts, it is desirable to lay brickwork in some natural bond as this not only increases the rigidity of the post but gives a beautiful effect.
Long, straight garden walls under 4 feet in height may be built 8 inches thick; over 4 feet high they should be 12 inches thick. If the walls are snort or reinforced at intervals with buttresses they may be only 8 inches thick provided they are not carried up over 6 feet. A footing is not needed but the foundation of common brick should extend below frost line. The wall should be finished on both sides with face brick, laid with cement-lime mortar in a natural bond, and should have a brick rowlock coping laid in rich cement mortar. Fig. 45 gives an idea of a garden wall with soldier base and rowlock coping.
Bond in brickwork is the overlapping of the brick one upon the other, either along the length of the wall or through its thickness, in order to bind them together into a secure structural mass. It is true, mortar is used to cement the brick together into a monolithic whole, but the real bond is the overlapping of the brick which the mortar serves to maintain. Units are shifted back and forth so that the vertical joints in two successive layers or "courses" do not come into line; in other words, the brick are laid so as to break joint, the whole forming a natural bond or a structural unity giving strength to the wall.
The strength and rigidity of a wall due to this bonding are clearly shown in Fig. 46. A concentrated load at any point on the wall is thus distributed over a larger area as indicated by the dotted arrows.
In speaking of brick bond, two terms are constantly recurring, viz., "stretcher" and "header." When a brick is laid lengthwise of the wall, thus showing its long, narrow dimension or "face" on the surface, it is called a stretcher. If its length extends back into the wall, so that its short dimension shows on the surface, it is called a header. The stretcher secures strength in the length of the wall. The header serves to form the transverse bond, that is, the strength of the wall through its thickness. When a brick is broken, as the case may require, the fragment is called a "bat." Bats are used either simply to fill in; or, as definite sized pieces, cut and used to make the bond come out right, in which case they are called "closures." While at certain points of the wall bats may be necessary, they should be sparingly used and then only according to the best practices of the craft.
In the old days, and indeed up to comparatively recent times, brick bond was used only in a structural or natural way, that is, to secure the strength of the wall as a solid mass; but in the seventeenth century European builders began to see an artistic possibility in the bond as it appeared on the surface. They began to see the fine tracery of the mortar joint running over the background of the brick, which could be varied into attractive patterns by different arrangement of the brick bond. As a consequence, there have been developed, in the main, three different types of bond, Running or Stretcher, English, and Flemish, which are used at the present day, with various modifications, to secure attractive effects in pattern.
When, as compared with the past, the great variety of brick colors and textures now offered is taken into consideration, it may be realized what charming results may be secured in the wall surface by the combination of brick patterns, colors, textures, and mortar joints.
The first and most obvious of these bonds is what is called Running or Stretcher Bond. The wall surface is made up of stretcher courses having at the corners a header which appears as a stretcher on the return side. This bond has the merit of being very strong longitudinally, but lacks transverse strength; consequently, it is modified into what is called Common or American Bond by laying a course of headers about every sixth course (Fig. 47). In order to maintain the effect of the running bond, a special double header bond is sometimes used as explained on page 19.
This method of using headers as in Common or American Bond, in order to secure transverse strength of wall, can be treated in a way to produce very much more pleasing effects, as may be seen in the English and Flemish Bonds.