Specification Sheet

Subfloors
All surfaces shall be dry, smooth and level. They must be structurally sound, solid, well
fastened clean and free from dust, oil and grease, paint, wax, old adhesives. Check for
curing and parting compounds, surface hardeners and sealers which are known to
interfere with the adhesive bond to concrete, as well as loosely bonded toppings, primers
or any other deleterious substances that may prevent or reduce adhesion.
Prior to the installation check any subfloor properly according to NWFA guidelines.
Any irregularities of the subfloors may telegraph through the cork flooring; make sure the
subfloor is evenly smooth and level.
New Concrete:
New concrete floors should be constructed, finished and cured ( minimum 30- 60 days) in
accordance with the American Concrete Institute (ACI) 302 “Guide for Concrete Floor
and Slab Construction” (Class 2 or 4) with a minimum compressive strength of 3,500
PSI (246 kg /cm²).
Before starting installation on concrete subfloors, moisture test must be conducted. The
Anhydrous Calcium KIT (calcium-chloride) has been designed to produce qualitative and
quantitative results. Emissions of moisture through the subfloor should not exceed 3
pounds /1,000 sq. ft. / 24 hours (1,36 kg/93m²/ 24 hours).
Alkali salts can be carried to the surface of concrete subfloors during the curing or where
excessive moisture conditions exist. These deposits can create adhesive bond failures.
The suitability of the slab can be determined with the use of pH testing paper or sticks. It
is suitable to install the flooring if the pH is under 10.
Wood Subfloors/ Underlayments:
Preferred underlayments such as plywood, particle board with 40 lb. per cu. Ft. density,
and OSB (oriented strand board) should have the APA trademark and be recommended
or guaranteed by the underlayment manufacturer or the wood flooring’s manufacturer.
The subfloor over which the underlayment will be installed must be smooth, dry properly
fastened and free of joint swelling, warping or delamination, multiply and tecply
underlayments have been approved as is APA-AC/BC EXTERIOR.
Other Subfloors:
Existing cement terrazzo and cement tiles must have full adhesion to the subfloor.
Remove all residues of maintenance agents and other materials that may deteriorate a
good adhesion. Prime any non porous subfloors with prime WAKOL D 3073 and level
with a high quality cement based underlayment in a minimum thickness pf 3/32”.