Floors & Counters

Subfloor or Base: Minimum 5/8" exterior grade plywood should be securely glued and fastened to floor joists or on counter base. Floor joists and counter framing should be spaced a maximum of 16" o.c.
Note: Floor trusses or
I-joists may be spaced 19.2" o.c. with 3/4" tongue-and-groove subfloor decking.

Underlayment: Using a 1/4" square-notched trowel, apply a setting bed of latex-Portland cement mortar (or thin-set mortar) to the subfloor or counter base. Immediately laminate PermaBase to subfloor or base leaving a 1/8" space between boards at all joints and corners. Leave a 1/4" gap along walls. Stagger all joints so that they do not line up with underlying substrate joints. Fasten PermaBase every 8" o.c. throughout board field and around all edges while setting bed mortar is still workable. Around perimeter of each board, locate fasteners 2" from corners and not less than 3/8" from the edges. Fill all joints solid with bonding material. On non-tapered joints such as butt ends, apply a 6" wide, 1/16" thick coat over the entire joint. For all joints, immediately embed 2" fiberglass mesh tape fully into applied bonding material; ensure that tape is centered over joint. Apply bonding material over fasteners to fully conceal. Remove all excess bonding material and allow to cure.