Subfloor Preparation

A: Luxury vinyl planks (LVP) conform exactly to the shape of the floor beneath them. If your concrete is not completely flat, the planks will flex under foot traffic. This constant flexing causes the locking mechanisms to snap and the floor to separate. We physically grind high spots and pour self-leveler in low spots to guarantee a perfectly flat, warranty-compliant foundation.

Ardex is a premium, high-strength cement-based patching compound. We use it to smooth out minor imperfections, fill joints, and create a flawless, seamless surface before installing glue-down LVT or hardwood. It dries rapidly and provides an incredibly strong bond that prevents future floor failure.

No. Extra padding or thick underlayment does not fix an uneven subfloor; it actually creates more vertical movement. That extra "squish" puts massive stress on the locking joints of your new flooring, leading to immediate failure. The only permanent fix is physically leveling the concrete or wood subfloor.

We use a 10-foot straight edge and laser levels during our field estimates to check for dips and humps. Industry standards require the concrete to be flat within 3/16 of an inch over a 10-foot radius. If the variance is outside that tolerance, we must grind the high spots and pour self-leveling compound in the low spots to ensure a successful installation.

Concrete grinding does produce dust, but our crews use commercial-grade HEPA vacuums attached directly to our grinders to capture it at the source. We also seal off the immediate work area with plastic sheeting to ensure the rest of your home stays clean during the preparation phase.

Yes, if we are pouring self-leveling concrete, baseboards must be removed. This ensures the liquid leveler flows completely to the structural edge of the wall, creating a perfectly flat surface for the new flooring and preventing your baseboards from getting permanently locked into the dried concrete.

While LVP can technically float over tile, the grout lines and uneven tiles will eventually cause the locking system to fail. To do it correctly, we either tear out the existing tile down to the concrete, or we use Ardex Feather Finish to completely fill the grout lines and skim-coat the entire tile surface so it is perfectly smooth before laying the new floor.

Many sales-led stores intentionally skip or hide subfloor prep to make their initial bid look cheaper. However, installing custom LVT or hardwood over an uneven floor instantly voids the manufacturer's warranty and guarantees the locking joints will snap. We are expert-led installers, meaning we evaluate the subfloor first and include the necessary prep work so your floor lasts a lifetime.

Soil movement in Northern California can cause older concrete slabs to settle. If LVT or hardwood is installed over dips or humps, the locking joints will snap and void the warranty. We grind high spots and pour self-leveling compound into low spots so your subfloor is perfectly flat before a single plank is laid.

Most franchise showrooms use a cheap, low-density pad to keep their "package price" low. At Harry’s Carpets, we recommend a high-quality 10lb density pad. It doesn't just feel better underfoot; it protects the carpet fibers from breaking down, which can add years to the life of your floor. Choosing the right pad is a small investment that saves you thousands by delaying your next replacement.