MILL CONSTRUCTION BUILDINGS 



Specifications 



ROOFING. First, lay one (1) thickness of sheathing paper or un- 

 saturated felt, weighing not less than five (5) pounds per hundred (100) 

 square feet, lapping the sheets at least one (1) inch. 



Second, lay two (2) plies of tarred felt, weighing fourteen (14) to 

 sixteen (16) pounds per hundred (100) square feet, lapping each sheet 

 seventeen (17) inches over the preceding one, and nail as often as is neces- 

 sary to hold in place until remaining felt is laid. 



Third, coat the entire surface uniformly with straight run coal-tar 

 pitch. 



Fourth, lay three (3) plies of tarred felt, lapping each sheet twenty-two 

 (22) inches over the preceding one, mopping with pitch the full twenty-two 

 (22) inches on each sheet so that in no place shall felt touch felt. Such 

 nailing as is necessary shall be done so that all nails will be covered by not 

 less than two (2) plies of felt. 



Fifth, spread over the entire surface a uniform coating of pitch, into 

 which, while hot, imbed not less than four hundred (400) pounds of gravel 

 or three hundred (300) pounds of slag to each one hundred (100) square 

 feet. The gravel, or slag, shall be from one-quarter (%) to five-eighths 

 (%) inches in size, dry, and free from dirt. 



FLASHINGS. Flashings shall be constructed as shown in detailed drawings. 



LABELS. All felt and pitch shall bear the manufacturer's label. 



INSPECTION. The roof may be inspected before the gravel or slag is 

 applied by cutting a slit not less than three (3) feet long at right angles 

 to the way the felt is laid. 



N. B. To comply with the above specifications, the material necessary 

 for each one hundred (100) square feet of roof is approximately as follows: 

 100 square feet sheathing paper, 80 to 90 pounds tarred felt, 120 to 160 

 pounds straight run coal-tar pitch, 400 pounds gravel, or 300 pounds slag. 



In estimating felt the average weight is practically fifteen (15) pounds 

 per one hundred (100) square feet, and about ten (10) per cent extra is 

 required for laps. 



In estimating pitch the weather conditions and expertness of the work- 

 men will aifect the amount necessary for the moppings and to properly bed 

 gravel or slag. 



The sheathing paper or unsaturated felt is placed on the bottom next to 

 the roof boards, mainly to keep any pitch which might penetrate the two-ply 

 felt above it from cementing the roofing to the sheathing. It also is of value 

 in preventing the drying out of the roof through open joints from below. 

 The saturated felts should be nailed where there is any chance of disturbance 

 of the roof from underneath by wind, and also enough to hold it in place 

 while laying. The practice in regard to nailing varies in different parts of 

 the country, but the fewer nails the better, so long as the roof is held in place. 



The contract price for this roof should not be less than the 

 cost of the materials specified, plus the cost of laying and a 

 reasonable amount for profit. Thorough inspection of ma- 

 terials and workmanship is recommended. 



Page thirty-three 



