8. Building Paper.    All surfaces to be covered with copper shall be covered first with rosin-sized or asbestos-felt paper weighing not less than 6 pounds per 100 square feet. Paper shall lap 2 inches and be nailed with flat-head copper nails.

9. Sheet-Copper.    Where shown on drawings or described in these specifications all sheet-metal of every description shall be of copper.

   All copper sheets used shall be rolled from copper conforming to the Standard Specifications of the American Society for Testing Materials.

   All copper sheets shall be plainly marked with the manufacturers' name and the weight.

10. Soft (Roofing Temper) Copper. Hard (Cornice Temper) Copper.    Except as otherwise specified, all copper throughout the work shall be of 16-ounce, soft (roofing temper) copper sheets.

   All leaders, eaves troughs, and molded hanging gutters shall be of 16-ounce, hard (cornice temper) copper.

11. Tin.    All tin used for tinning seams for soldering, etc., shall be best grade, pure metal.

12. Solder.    All solder shall be of the best grade, equal to Specification B-32 of the American Society for Testing Materials, and shall be composed of one-half pig lead and one-half block tin (new metals).

13. Flux.    Rosin shall be used as a flux.

14. Nails and Fastenings.    All nails, rivets and similar fastenings used throughout the work shall be of best grade hard copper or brass.

   Nails shall be wire nails not less than No. 12 gage and not less than ⅞ inch long.

15. Tinning.    The edges of all sheets to be soldered shall be tinned 1½ inches on both sides. Rosin shall be used as a flux.

16. Soldering-Coppers.    All soldering shall be done with heavy soldering-coppers of blunt design, properly tinned before use. They shall weigh not less than 6 pounds to the pair. For flat seam work on decks, in gutters, etc., they shall weigh not less than 10 pounds to the pair.

17. Soldering.    Soldering shall be done slowly with well-heated coppers so as to thoroughly heat the seam and completely amalgamate the tin with the solder. Plenty of solder shall be used and the seam shall show when finished at least one full inch of thick, evenly flowed solder.

18. Slopes of Roofs.    On roofs having a slope of less than 1 on 4 all flat and lap seams shall be soldered. On roofs having a slope of 1 on 4 or greater, flat and lap seams shall not be soldered.

19. Seams.    Standing Seams shall finish not less than 1 inch high.

   Mat, or Lock, Seams shall finish not less than ½ inch wide.

   Lap Seams, where soldered, shall finish not less than 1 inch wide.

   Lap Seams not soldered shall lap at least 3 inches.

   All Flat and Lap Seams shall be made in the direction of the flow.

20. Double Lock Seams.    Sheets to be double or copper-locked shall have a 1½-inch turn-up at the edges which shall be folded over with the edge of the adjoining sheet three complete turns so that the finished seam shall be 6-ply and shall finish ½ inch wide. The seam so formed shall be malleted down and on flat surfaces the edge shall be tipped with solder.

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