1. Inspect & clean the subfloor
Start with a sound, clean base. Remove old adhesive, paint, laitance and dust. Check concrete slabs for cracks, hollow areas and movement — repair these before you go any further, as any defect will telegraph through the finished floor.
2. Test for moisture
Excess moisture is the single most common cause of flooring failure. Use a hygrometer (relative humidity) or calcium carbide test and confirm the reading is within the floor covering and adhesive manufacturer's limits. If it's too high, fit a surface damp-proof membrane before proceeding.
3. Choose & apply the right primer
Primer controls porosity and improves the bond of your levelling compound. Match it to the substrate: an absorbent primer for sand/cement screeds, a bonding primer for smooth non-absorbent surfaces, and an epoxy DPM where residual moisture is a concern. Apply evenly and let it cure.
4. Apply a levelling compound
A self-levelling compound gives the flat, smooth finish that quality flooring demands. Mix to the correct consistency, pour, and spread with a trowel or spiked roller to release air. Build up depth in line with the product's stated minimum and maximum thicknesses.
5. Cure, check & install
Let the compound fully cure before laying anything on top. Re-check flatness with a straight edge and re-test moisture if curing has been slow. Only then move on to your underlay, adhesive and floor covering.
Everything you need to prep a subfloor
From damp-proof membranes and primers to self-levelling compounds, we stock the trade-grade products to get your subfloor ready.
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