Apply Fiberock® panels to subfloor using 1/4" x 1/4" square notch trowel with Type 1 organic adhesive or latex-modified thin-set mortar or dry-set mortar. Fasten to subfloor with 1-1/4" Durock™ brand tile backer screws for wood framing (or equivalent) or 1-1/2" hot-dipped galvanized roofing nails spaced 8" o.c. in both directions withperimeter fasteners at least 3/8" and less than 5/8" from ends and edges.