Acclimation

Acclimate boxes flat in the installation room for 48 hours at 65–85°F and 35–65% relative humidity before installing.

Pro tip: SPC doesn’t need acclimation the way hardwood does, but the install room should be at its normal operating temperature during install — not 60°F in winter or 90°F in summer. Install at the temperature the room will typically be. This minimizes edge-gap changes after the floor settles.

Subfloor flatness

Subfloor must be flat to within 3/16 inch over 10 feet. Fill low spots and grind high points before installation.

Pro tip: If the subfloor has small unevenness that can’t be fully leveled, thicker SPC provides more physical forgiveness — 8mm and 10mm planks bridge minor dips and bumps better than 6.5mm. Rule of thumb: under 1/8-inch variance over 10 feet, any SPC thickness works. 1/8 to 3/16-inch — go 8mm minimum. Over 3/16-inch, the subfloor needs leveling compound before install regardless of plank thickness. Important caveat: even if thicker SPC masks the problem physically, manufacturer flatness specs are flatness specs. If a warranty claim gets filed later and the inspector measures out-of-spec subfloor, that goes in the report as installation-related — regardless of whether thicker plank was used to “compensate.” Thicker SPC is forgiveness for minor borderline cases, not license to skip subfloor prep.

Moisture testing (concrete)

Test concrete subfloors per ASTM F1869 (≤ 5 lbs/1000 sqft/24hr CaCl) or ASTM F2170 (≤ 80% RH).

Pro tip: One moisture test is a snapshot, not a seasonal profile. Slab moisture in the Bay Area can swing 10-15 percentage points between wet and dry seasons. If your test passes in summer, retest in winter before committing, or just install the 6-mil vapor barrier as standard practice.

Moisture barrier (concrete subfloors)

A 6-mil polyethylene moisture barrier is required over concrete subfloors. Not required over wood subfloors that pass moisture testing.

Pro tip: We’ve replaced too many vinyl floors that failed from slab moisture in Bay Area homes — many built on fill or near old creek beds. Even when the slab tests dry today, seasonal water table shifts can push moisture up through the concrete years later. 6-mil polyethylene sheeting is $30-50 per room and takes 20 minutes to install. Always install it over concrete, regardless of what the manufacturer spec says is “required.”

Underlayment (do not replace the attached pad)

No additional underlayment required — 1.5mm IXPE anti-microbial acoustic pad is factory-attached.

Pro tip: The attached anti-microbial acoustic IXPE pad is part of the warranty contract, not an accessory. Adding foam, cork, or rubber underneath voids the structural integrity coverage. If the subfloor is irregular, fix that with leveling compound first — don’t stack pads to mask a subfloor problem.

Installation method

Floating click installation. Leave 1/4-inch expansion gap at all walls and fixed objects. Do not glue or nail.

Pro tip: Check the manufacturer spec for T-mold requirements between rooms — some brands require a T-mold at every doorway, others allow continuous install up to a certain run length. Don’t skip the check. If you run one continuous floor through a kitchen into a hallway and into two bedrooms without T-molds, each room’s subfloor shifts slightly differently with seasonal humidity and thermal changes. That differential movement concentrates at the narrow door transitions, and within 1-2 years you’ll see click-lock seams crack right at the doorways — not mid-room, always at the pinch points. T-mold at each doorway absorbs the differential movement and isolates each room’s expansion from the next.

Radiant heat compatibility

Radiant heat compatible. Maximum surface temperature 80°F. Heat must rise gradually (no more than 5°F per hour during initial warm-up).

Pro tip: Per manufacturer: Radiant heat compatible. Maximum surface temperature 80°F. Heat must rise gradually (no more than 5°F per hour during initial warm-up). The surface temperature cap is the critical number. Hydronic systems typically run below spec naturally; electric mats can exceed it if the thermostat is mis-positioned. Position the sensor in the finished floor, not in the slab, and verify with an infrared thermometer before tiling furniture or rugs on top.

Daily maintenance

Sweep or dry-mop regularly. Clean with a damp mop and pH-neutral cleaner. Never use wax, polish, steam mops, or abrasive cleaners.

Pro tip: The fastest way to wear out the wear layer is tracked-in grit. Walk-off mats at every entrance plus twice-weekly vacuuming (hard-floor setting, no beater bar) in high-traffic areas buys years of finish life. The wear layer handles traffic; abrasive grit grinds it down prematurely.

What to avoid

Avoid prolonged direct sunlight without UV-protective window film. Do not use rolling chairs without protective floor mats.

Pro tip: Rubber- and latex-backed walk-off mats cause permanent yellow discoloration under SPC warranties. The rubber chemistry reacts with the wear layer over months. Use felt-backed or woven natural-fiber mats instead — and never leave any mat in place over a seam line.

Furniture and pet protection

Use felt pads under all furniture legs. For heavy items, use wide-base coasters to distribute weight.

Pro tip: If you have pets, avoid heavy wire-brushed or deeply-rustic surface textures. The deep grain grooves that make wire-brushed look authentic also trap pet hair, dirt, and grit. Vacuum can’t reach the deepest channels; over months, the floor looks permanently soiled even after cleaning. For pet homes, choose subtle-to-medium surface texture instead — still gets the wood-grain realism, skips the cleaning liability. Heavy wire-brushed SPC photographs beautifully in the showroom but doesn’t live well with dogs and cats.

Similar medium grey tones from Medieval Floors: