Installing a wood floor is a skilled trade, and the quality of the installation determines how long the floor performs and how it looks. Even the finest boards will fail quickly if laid on a poorly prepared subfloor, without adequate acclimatisation, or using the wrong fixing method. This guide covers what to expect from the installation process and how to choose the right installer for your project.
Subfloor Preparation: The Most Critical Step
The subfloor must be flat, stable, dry, and structurally sound before any wood flooring is laid. For timber subfloors, this means checking for loose or squeaky boards, punching down any protruding nail heads, and confirming the subfloor moisture content is below 12%. For concrete, the screed must be fully cured and the relative humidity at depth below 75% RH (tested with an in-situ probe — surface testing is not reliable for this purpose). Any high spots must be sanded or ground flat; any dips must be filled with a suitable floor-levelling compound. Skipping this step is the most common cause of floor failure after installation.
Installation Methods: Floating, Gluing, and Secret Nailing
The correct installation method depends on the floor type, subfloor construction, and whether underfloor heating is present:
- Floating (click-lock or tongue and groove): Boards interlock and are not fixed to the subfloor — suitable for most engineered floors on timber or concrete, and over acoustic underlays. Quick to install and reversible.
- Fully bonded (glued): Boards are adhered to the subfloor with elastic polyurethane adhesive. Required for most UFH installations and for solid boards on concrete. The adhesive’s flexibility accommodates seasonal movement without stress on the joints.
- Secret nailed: Boards are blind-nailed through the tongue into timber joists or a plywood subfloor. The traditional method for solid hardwood; provides a rigid, squeak-free floor with no surface fixings visible.
What a Professional Installer Does
A qualified flooring installer will begin by assessing the site before any boards are delivered. This assessment covers subfloor flatness (checked with a 2m straightedge — tolerances are typically ±3mm over 2m), moisture content at multiple points across the floor, the suitability of the existing subfloor for the chosen laying method, and any structural issues that need resolving first. They will confirm the acclimation requirements for your boards, advise on the correct underlay and adhesive if applicable, and lay out a plan for the direction and starting point of the installation before cutting a single board.
How Long Does Installation Take?
An experienced installer working alone can typically lay 15–25m² of engineered floating floor per day, depending on the room’s shape, the number of obstacles (alcoves, hearths, pipe penetrations), and the complexity of the pattern. Solid wood installation is slower — around 10–15m² per day for secret nailing, less for glue-down. A two-person team can cover larger areas more quickly. Add time for subfloor preparation if levelling compound is needed (24–48 hours drying time) and for fitting door bars, beading, and skirting reinstatement after the floor is down.
Choosing the Right Installer
Look for an installer with specific hardwood flooring experience — it is a different skill set from laminate or vinyl installation. Ask to see examples of previous work, particularly in your chosen floor type, and check whether they carry the correct tools: a specialist hardwood nailer (portanailer), moisture meters, straight edges, and diamond blade saws for stone thresholds. Established installers will be happy to carry out a site visit before quoting. Be cautious of very low quotes — flooring installation is labour-intensive, and a price that seems too good to be true usually reflects either inexperience or corners being cut in the preparation stages.
After Installation: What to Expect
Newly installed wood floors need a settling-in period. For floating floors, avoid walking on them for at least 24 hours to allow adhesive at any glued joints to cure. For glue-down installations, the curing time is longer — typically 48 hours before normal use. In the first year, small gaps may appear between boards during the winter heating season as the floor reaches its first full seasonal EMC cycle. This is normal and expected. If significant cupping, buckling, or persistent gapping occurs, contact your installer promptly — most reputable installers provide a workmanship guarantee, and post-installation issues are usually traceable to subfloor preparation or environmental conditions that can be identified and addressed.