Brick buildings with pitch roofs require a wooden wall plate to receive the ends of the rafters; the plate also greatly stiffens the wall to resist the thrust of the rafters. It should be made of two thicknesses of plank, 8 inches wide for an 8 or 9-inch wall and 12 inches wide for thicker walls, and should be bolted to the top of the wall by ¾-inch or 7/8-inch bolts at least 2 feet long, imbedded in the brickwork. On the lower end of the bolt a large washer of wrought iron should be placed to hold the bolt in the wall. The planks should break joint, and where possible the plate should form an unbroken tie around the building. Before bolting the plates in position they should be bedded in mortar. For small dwellings a single plank is sufficient, but it should extend from angle to angle. The rafters are spiked to the plate, as in wooden buildings, and often the attic joists rest on the plate and are spiked to it. (See Figs. 78 and 83.) When the plate is above the attic floor diagonal ties or braces should be spiked to the rafters and to the floor joists, as in Fig. 78, to prevent the roof from spreading the walls.
The rafters of flat roofs are built into the wall in the same way as the floor joists, and the wall carried 12 or 18 inches above the roof.