Fire-retardant plywood decking is not an approved substrate for shingles. For non-standard decks, please contact the Elk location nearest you. Fasteners shall be of sufficient length and holding power as required on shingle wrapper for securing material. For areas where discoloration of roofing granules caused by growth of the blue-green algae, Gloeocapsa, is a problem, shingles shall be Prestique I with StainGuard treatment , as manufactured by the Elk Tuscaloosa, Alabama and Ennis, Texas plants. Complete installation instructions are published by Elk and printed on the back of every shingle bundle.
All warranties are contingent upon the correct installation as shown on the instructions.