THE wooden floors of breweries, abattoirs, stables, etc., are frequently waterproofed as shown in the following sketch.

The felt and pitch are laid as shown in the roof specification over boards, the top course of plank should be laid in hot pitch and so nailed that the nails all enter the beams below, as nailing between beams is liable to cause leaks. The joints of the upper course of plank should be run with hot pitch.

   This system is applicable to waterproofing between two layers of concrete, as in flooring or vault arches, over which a Portland Cement or other floor or sidewalk material is laid.

   Waterproof floors laid similar to this method, consisting of at least two thicknesses of tarred felt placed between a double boarded floor, cemented together with pitch with the upper floor nailed while the pitch is in a tacky condition, secure an allowance of 5% in the schedule rate of buildings made by the N, Y. Fire Insurance Exchange — the object of this being to prevent damage by water in case of fire.

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