Copper Flashings - A Manual - 1925 - Page 32
29. Cap Flashings or Counter-Flashings. Cap flashings shall turn down over base flashings not less than 4 inches. They shall be secured to vertical surfaces as follows:
(—1.) Wood Work. They shall extend up under exterior coverings such as shingles, slate, etc., at least 2 inches above the butt of the second course, and in no case less than 4 inches above the roof, and shall be nailed along the top edge about every 8 inches.
(-2.) Mason Work. They shall extend into joints of masonry walls 4 inches and have the inner edge turned back on itself ½ inch. The sheets shall be bent to the required shapes, and built in with the mason work. No cutting-out of joints for setting flashings will be allowed.
(-3.) Reglets. They shall be secured, as specified below, in reglets cut in the masonry.
(—4.) Stucco on Wood. When used with stucco-covered wood-frame walls, cap flashings shall be formed over a ⅞-inch base board and extend up the wall at least 2 inches above the base board, and be nailed at the top edge with nails about 8 inches apart. Metal lath shall be placed over the flashing and the stucco shall be finished against the base board.
(-5.) Stucco on Masonry. They shall be built into the masonry as the work progresses and shall project out from the wall as required and turn down over the base flashing. The stucco shall finish against the cap flashing.
(-6.) Concrete Walls. They shall be set in the forms before the concrete is poured. They shall extend into the wall at least 2 inches and shall have the inner edges turned back ½ inch.
30. Flashings. (Masons' Specification.) Where indicated on the plans or specified build in all flashings furnished by the sheet-metal contractor and as directed by him.
31. Step Flashings. Step flashings shall be used where vertical surfaces occur in connection with slopes.
(-1.) They shall be formed of separate pieces built into the masonry as specified for cap flashings in masonry. Steps shall lap generally 3 inches, but in no case less than 2 inches, and shall not be soldered.
(-A.) Lap joints shall be vertical.
(-B.) Lap joints shall be normal to the slope of the roof.
(-2.) They shall extend into the wall one course of brick and turn up 1 inch in back. Each piece shall be formed to lap the next piece below 1 inch on the sides, and as each piece is set both the horizontal and vertical joints shall be soldered to the piece below so that the finished flashing shall form a complete watertight cap.
32. Vent Flashings. All pipes passing through roofs shall be flashed and counter-flashed. Base flashings shall extend out on the roof not less than 6 inches.
(-1.) They shall be of sufficient length to cover the roofing course next below the pipe and to extend up under the roofing course above as far as possible without puncture by nails.
(-2.) Where vent-pipes extend more than 12 inches above the roof the counter-flashing shall be caulked into the hubs or held with brass clamps embedded in elastic cement or white lead. It shall lap the base flashing at least 4 inches.
(-3.) Where the vent extends not more than 12 inches above the roof surface, it shall be flashed as follows:
Cast-iron Pipe. The base flashing shall be carried up to within an inch of the top of the pipe and shall be counter-flashed by a copper cap 6 inches high, turned over and down into the pipe at least 2 inches.
Threaded Pipe. The base flashing shall extend up to within 2 inches of the end of the pipe, which shall be threaded. After the flashing is in place the threads shall be covered with white lead and an iron or steel cap, of such design as to enclose the flashing material, shall be screwed onto the pipe.
(-4.) Patented vent-flashing devices may be used, subject to the approval of the architect. They shall be made of 18-ounce copper, shall be the product of a recognized manufacturer, and shall be installed according to manufacturer’s directions.
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