This section is from the book "The Principles And Practice Of Modern House-Construction", by G. Lister Sutcliffe. Also available from Amazon: How Your House Works: A Visual Guide to Understanding & Maintaining Your Home.
Tile-hung walls have been frequently constructed in recent years, especially for country houses. Buildings in which weather-tiling is adopted usually have the lowest or ground story built entirely of brickwork, the upper stories only being finished with tiles.
Weather-tiles may be rectangular, or may have the lower edges shaped in various ways in order to add to the effect, as shown in Fig. 53. The usual size is 10½ inches by 6½ inches by ½-inch, but smaller sizes can be obtained. In the head of each tile two holes are pierced, through which pegs or nails are driven to secure the tile to the laths or wall. Sometimes also there are two projecting "cogs" or "nibs" on the back upper edge for hanging the tile to the wood lath or other projection. The tiles are laid in courses, each course being overlapped by that above; the length of tile remaining exposed is said to be the "gauge" to which the tiles are laid, as at B in Fig. 55. For roofs the gauge is usually 3, 3½, or 4 inches, or - to speak in slater's parlance - the tiles (if 10½ inches long) are laid to a "lap" of 4½, 3½, or 2½ inches, lap being the amount by which any course of tiles is overlapped by the next but one course above it. For walls the lap is usually less than for roofs, as there is less danger of rain and snow being driven between the tiles. Sometimes the tiles are slightly curved from head to tail, the upper or exposed side being convex, and the other side concave; this is done in order that the tail of the tiles may lie more closely upon those below. The upper part of each course of tiles should be covered with good mortar, to form a bed for the next course. This prevents rattling, and helps to keep the wall warmer and drier.
Timber-framed walls, as shown in Fig. 54, are sometimes constructed to receive the weather-tiling, the framework consisting of horizontal sills or head-pieces with vertical battens or studs framed into them, and struts and braces as required To the vertical studs, horizontal deal or oak laths (about 1½ inches by 1 inch) are nailed, to which the tiles are secured by pegs or nails. The framework is finished inside with laths and plaster. This arrangement is doubtless as warm and dry as a roof of similar construction, but, as the hollow spaces are likely to harbour dirt and vermin, and as the timber framing Weather tiling certainly adds to the combustibility of the house, the method of construction has little to recommend it save its cheapness. Indeed, the danger arising from these timber-framed walls is so great, that they are forbidden by the building-regulations of most towns and cities.
Fig. 53- Various Shapes of Tiles.
Fig. 54 with Timber framed Wall covered with.
A warmer and drier arrangement consists in covering the battens outside with boarding and felt before fixing the tile-laths, as in the better kinds of roofing, but this increases the combustibility of the structure and leaves the cavities intact. If the spaces between the studs be filled with silicate cotton or slag-wool, or with brickwork as in brick-nogged partitions, the wall will be cleaner and more fire-resisting. When all is done, however, there is the danger of the woodwork decaying, a danger which was never greater than it is to-day, as never before has there been so much young and sappy wood in the market.
Brick walls furnish a far more satisfactory backing for the tiles. They may be hollow, as shown in Fig. 55, or solid, as shown in Fig. 56, and the tiles may be secured to the walls directly by means of zinc or galvanized iron nails driven into the joints of the brickwork. The ^aiiu't-of the tiling will, of course, be regulated by the thickness of the courses of the brickwork, and as this is, as a rule, only 3 or 3¼ inches, giving a greater lap than is necessary, the bricks are sometimes laid on edge, and the gauge becomes about 4½ inches. This arrangement is shown in Fig. 55, but it cannot be recommended for exposed situations, as it gives a lap of 1½ inches or less. A better method consists in laying the bricks flat as usual, and forming mortar-joints about 1 inch thick, so that the gauge of the tiling will be not more than 4 inches. This is a method adopted by Mr. Ralph Nevill, F.S.A.: the mortar used by Mr. Nevill for the thick joints is made of ashes and selenitic lime, " with a dash of Portland cement". The bonding of the brickwork in this kind of wall it clearly shown in Fig. 56.
Unless the mortar is of such a nature as to afford good hold for the nails, there is danger of the tiles being stripped by the wind in exposed situations. To prevent stripping, wood fillets are sometimes built into the brickwork every six or eight courses, and to these vertical laths are nailed, which in turn receive the horizontal tile-laths. By these means the tiles are securely held, but the wood is sure to decay sooner or later. A better method, which is sometimes adopted, consists in nailing the tiles directly to fixing-blocks, specially made of a kind of concrete. Those made by Wright measure 9 inches by 5 ⅛ inches by 1½ inches, and are laid in continuous courses alternately with courses of bricks, as shown in Fig. 57. The projection of the blocks is useful for supporting the nibs of the tiles, if the tiles are nibbed, but in any case the tiles should be nailed to the blocks.
Fig. 55.-Hollow Brick Wall with Bricks on edge covered with Weather-tiling.
Fig. 56 -Brick Wall with Thick Joints to receive Weather tiling.
Special tiles, of suitable lengths according to the gauge, are made for the lowest course or eaves, as at a in Fig. 55, and also for the top or ridge-course, while the angles of the wall are formed with angle-tiles, known as "square" or "octagonal " according as they arc adapted for angles of 90° or 1350. Square angle-tiles for a salient angle are shown in 54. Tiles 9¾ inches wide, known as tile-and-half, are used in alternate courses where necessary in order that the tiles may "break joint" (see Fig. 53), or half-tiles are used for that purpose.
A short account of Borne different qualities of tiles will be found in Chapter VII (Lightning-Conductors). of this Section. Suffice it now to say that with good tiles properly laid, brick walls may be rendered warm, dry, and durable. Of the picturesqueness of many old and modem tile-hung houses there can be no manner of doubt.