Prime Grade Solid Oak Overlay Blocks – Unfinished, Tumbled/Distressed 10x60x300mm (2.16m2 pack)

🔧 Site Conditions

• fully enclosed, with doors and windows installed and all wet trades (e.g. plastering, screeding, painting) fully complete and dry.
• Room temperature should be maintained between 16–24 °C, with relative humidity between 45–65% before, during, and after installation.

Subfloor moisture content must not exceed:

• Concrete or screed: 2%
• Anhydrite screed: 0.5% (or 0.3% with underfloor heating)
• Timber subfloors: 12%, and no more than a 2% difference from the flooring itself
• Subfloor flatness tolerance: The surface must be flat within 3mm over a 2-metre span. High spots should be ground down and low spots filled using a suitable levelling compound.

📦 Acclimatisation

• All flooring must be acclimatised in the room of installation for a minimum of 48 hours before fitting.
• Keep packs sealed and stacked flat, away from direct heat or moisture sources.
• For underfloor heating installations, extend the acclimatisation period and ensure the heating is running at ambient levels during this time.

🟢 Floated Installation - Underlay - T&G Adhesive

• Suitable for engineered plank floors (not herringbone) that have a click or tongue-and-groove profile

Can be floated over:

• Concrete or screed
• Chipboard or plywood
• Flat, sound floorboards — provided they are secure, dry, and meet the flatness tolerance (3mm over 2m)

Maximum size without expansion breaks:

• 6 metres wide x 10 metres long
• Beyond this, use T-sections or expansion joints
• Do not install floating floors under fixed items like kitchens or heavy fitted furniture — in these areas, use a fully bonded installation.
• Use a high-quality underlay, ideally with an integrated moisture barrier, or a low-tog underlay when installing over underfloor heating (We always advise fully bonding installation over underfloor heating).
• Leave a 15mm expansion gap around the full perimeter and all fixed objects.

Products: Underlays

🟠 Fully-Bonded Installation - Bona R848

• Recommended for all Wood floors, and mandatory for all herringbone installations.

Can be bonded directly to:

• Concrete or screed
• Plywood or chipboard
• If installing over existing floorboards, they must first be overlaid with a minimum 6mm plywood to create a flat, stable base.
• Use a flexible wood flooring adhesive, applied using the correct notched trowel, ensuring full coverage — spot bonding is not permitted.
• Maintain 10–15mm expansion gaps at all walls, door frames, and fixed structures.

🔵 Nailed & Screw- Down Installation - Screws - Nails

• Only suitable for 18mm or 20mm thick plank flooring — not suitable for herringbone.

Can be installed directly onto:

• Timber joists
• Structural-grade plywood
• Boards should be secret nailed/screwed through the tongue, with appropriate spacing between fixings to ensure tight, secure installation.
• Always install a suitable vapour control layer over joists or between flooring and any crawl space below.

FLOOR PROTECTION AND COVERING

• If further works are required after the flooring has been installed, we recommend covering the entire floor area, not just isolated patches.
• For areas with underfloor heating, use a breathable floor protection such as Prep-Board or a similar product to prevent heat build-up and condensation.
• For areas without underfloor heating, most general-purpose floor coverings are suitable — always confirm with your builder or site manager before use.

• The surface temperature of the wood flooring must never exceed 27 °C. This includes areas beneath rugs and furniture.
• Use a floor sensor thermostat (not just room temperature control) to monitor and maintain the correct temperature.
• After installation, wait at least 48 hours before switching on underfloor heating. Begin with a low temperature and increase gradually.
• Maintain a stable environment during and after installation — ideally 18–21 °C room temperature and 40–60% relative humidity.
• Engineered wood flooring is the most suitable choice for underfloor heating. Fully bond boards to the subfloor using a compatible adhesive.
• Ensure good insulation beneath the heating system and use layers that distribute heat evenly to avoid hot spots.
• Avoid thick rugs or heavy furniture that can trap heat and cause the floor temperature to exceed 27 °C.
• Underfloor heating must be installed and commissioned by qualified professionals. Always follow local regulations and ensure proper documentation.
• Failure to follow these guidelines or exceeding the maximum surface temperature may or cause damage to the flooring.