Installation Guide

Engineered hardwood floors may be installed over any structurally sound subfloor that is flat, clean and dry on all grade levels. All subfloors should be:
• Clean: Subfloor must be clean and free of dirt, curing compounds, drywall mud, wax, paint, oil, sealers, adhesives and other debris. These may be removed
mechanically. Do not install glue down floors over chemically cleaned substrates.
• Flat: Subfloor must be flat within 3/16” in 10’ radius (5 mm in 3 m) and/or 1/8” in 6’ radius (3 mm in 2 m). Sand high areas or joints. Fill low areas with a high
compressive strength
(min. 3,000 psi) Portland based compound. Vertical deflection must not exceed 3/16”.
• Dry: Wood floor moisture should be evaluated using the guidance supplied above under the heading Job Site Conditions. Concrete subfloors must be
cured for a minimum of 60 days. The moisture content of a concrete subfloor should be tested using an in-situ probe and show <75% RH
(ASTM F2170). Test
results must be recorded on page 10 of these instructions and left as a permanent record of testing with the homeowner. If moisture levels exceed these
limits, DO NOT INSTALL the flooring until appropriate corrections are made or select the appropriate moisture mitigation adhesive listed on pages 5-6.
NOTE: Basements and crawl spaces must be dry. Use of a 6-mil black polyethylene membrane is required to cover 100% of the crawl space earth. Crawl space
clearance from ground to underside of joist should be no less than 18” and perimeter vent spacing should be equal to 1.5% of the total square footage of the
crawl space area to provide cross ventilation. To increase reliability, appropriate subfloor moisture testing should be performed after the HVAC system has been in
operation for a minimum of 5 days. Excess moisture on any flooring substrate, if not identified and corrected prior to installation, will cause floor covering failure.
Our Warranties DO NOT cover any problems due to moisture levels that exceed these guidelines.
Structurally sound wood subfloor: Nail or screw any areas that are loose or squeak. Vertical
deflection must not exceed 3/16”. Wood panels should exhibit an adequate fastening
pattern, glued, screwed or nailed as system requires, using an acceptable nailing pattern,
typically 6”
(15 cm) along bearing edges and 12” (31 cm) along intermediate supports. Flatten
edge swell as necessary. Replace any water damaged, swollen or delaminated subflooring
or underlayment.
Building codes establish requirements for structural support components of flooring systems
which may not provide adequate rigidity and support for proper installation and performance
of a hardwood floor. Whenever possible, install flooring perpendicular to the floor joists for maximum stability.
NOTE: When joist spacing exceeds the traditional 16” on center, manufacturer recommends you apply a thin bead of Performance Accessories Tongue & Groove
D3 glue to the bottom side of the groove to lock the tongue and groove profile in place. This will reduce the potential for movement of the tongue and groove,
which may contribute to squeaking or crackle. When using this method of installation, you may continue to choose to staple or nail down the hardwood
depending on your preference. Using a D3 tongue and groove glue with the staple reduces movement as the sub-floor deflects.
Structurally sound concrete subfloor: Concrete substrate should be at least 60 days old and constructed in accordance with ASTM E1745. Level substrate and
fill all cracks, holes and low spots with a polymer modified Portland cement patch or leveling compound. Burnished or steel troweled concrete substrates must
be inspected for porosity by placing a few drops of water on the surface. If the water is not absorbed within 3 minutes, the substrate should be considered non-
porous. Abrade the surface with 30-grit sandpaper until porosity is achieved. After abrading, remove all debris before proceeding with installation. Glue down
floors may be applied to concrete with a rating of 3,000 psi or greater. Glue down application over lightweight concrete
(less than 3,000 psi) is not permissible.
Wood Subfloors
Approved subfloor panels should meet or exceed the following guidelines:
• Plywood: Must be minimum CDX EXP 1 grade and conform to U.S. Voluntary Product Standard PS1 performance standard or Canadian performance
standard CAN/CSA 0325-0-92.
• Oriented: Strand board (OSB) must conform to U.S. Voluntary Product Standard PS2 or Canadian performance standard CAN/CSA 0325-0-92. The panels
must be tongue and groove and installed sealed side down.
• Particleboard: Must be a minimum 40-lb. density, stamped underlayment grade and 3/4” (19 mm) thick. (Floating installation only)
Floor joist/truss spacing will determine the minimum acceptable thickness of the subfloor panels. Joist/truss spacing of 16” on center or less for single panel
subflooring requires a minimum 5/8”
(19/32”, 15.1 mm) CDX (exposure 1) 4’ x 8’ subfloor panels. Joist/truss spacing of greater than 16”, up to 19.2” (488 mm)
on center, requires a minimum nominal 3/4” (23/32”, 18.3 mm) tongue and groove CDX EXP 1 plywood or OSB 4’ x 8’ subfloor panels, glued and mechanically
fastened. Floor systems with joists/truss spaced greater than 19.2”
(488 mm) on center up to a maximum of 24” (610mm) require minimum 7/8” tongue and
groove CDX EXP 1 plywood or OSB 4’ x 8’ subfloor panels, glued and mechanically fastened. Installation over joist spans greater than 24” on center is not
recommended. For installation over joist spans greater than 24” on center, consult NWFA for panel thickness guidance.
Solid Wood Subfloor — Direct Glue or Staple Down Applications
• Minimum 3/4” (19 mm) thick with a maximum width of 6” (15 cm) installed at a 45° angle to the floor joists.
• Group 1 dense softwood (pine, larch, Douglas fir, etc.) No. 2 common, kiln dried with all board ends bearing on joists.
• For direct glue down applications add 3/8” (9.5 mm) approved floor panel underlayment.
Existing Wood Flooring — Direct Glue or Staple Down Applications
• Existing engineered flooring must be well bonded/fastened. When gluing over existing wood flooring, the surface finish must be abraded or removed to
allow adequate adhesive bond.
• Existing solid hardwood flooring that exceeds 6” (15 mm) in width must be covered with 3/8” (9.5 mm) approved underlayment and fastened as required.