(To be included in Carpenters' Contract.) [western method ]
350. - Cover the flat roof with five ply gravel roofing, put on in the best manner. The first layer to be of heavy dry felt, put on with 2-inch lap. The other four layers to be of------------brand saturated felt, (25) pounds to the square. Put on in courses parallel with the eaves, each layer lapping the one below 27 inches, so that the roof will be five layers in thickness over all its parts, and to be well mopped for a distance of 9 inches from the edge with hot pitch. Secure the felt to the roof by 3d. nails with tin discs, driven in rows 10 feet apart and 12 inches apart in the rows.* Cover the entire surface of felt, flashings and back of fire walls with a continuous and even coating of straight run coal tar pitch and cover the same immediately with a sufficient body of well-screened gravel. If the roof is laid in cold weather the gravel is to be applied hot.
Flashing. - Finish the roofing against fire walls, chimneys, scuttle and skylight by turning the felt up 4 inches against the wall. Over this lay an 8-inch strip of felt with half its width on the roof. Fasten* the upper edge of the strip and the several layers of felt to the wall by laths or wooden strips securely nailed, and press the strip of felt into the angle of the wall and cement to the roof with hot pitch Nail the lower edge of the strip to the roof every 4 or 5 inches. Take especial care in fitting around the angles of chimneys and skylights. Extend the felt 6 inches up on pitch roof, and secure every 4 inches with 3d. nails with tin washers.
351. - [In the New England States the saturated felt is often put on one layer at a time, in which case the first paragraph above should read as follows:]
Cover the flat roof with one layer of heavy dry felt and four layers of saturated felt (weighing 25 pounds to the square), lapped 3 inches and the edges cemented with hot pitch. Each layer to be laid separately, and the last two layers to be laid in hot pitch Secure the last layer to the roof, at the laps, by 3d. nails with tin washers, spaced 30 inches apart. Pitching and gravel same as above.
[Still another method of applying the saturated felt is to apply three layers as in the Western method, each layer lapping 24 inches, then cover with pitch and apply one or two more layers of felt separately in hot pitch. This makes a very good and durable roof.