How to Prepare a Subfloor Before Installing New Flooring

No matter what type of flooring you're installing, proper subfloor preparation is essential for achieving a professional, long-lasting finish. A poorly prepared subfloor can lead to uneven surfaces, adhesive failure and premature wear, costing both time and money to rectify.

Whether you're laying LVT, vinyl, carpet or wood flooring, following the correct preparation process will help ensure the best possible results.

1. Check the Subfloor Condition

Before starting any installation, inspect the subfloor for cracks, holes, old adhesive residues and any signs of damage. The surface should be clean, dry and structurally sound before any further work is carried out.

Any loose material, dust or contaminants should be removed to create a solid base for repairs and levelling.

2. Test for Moisture

Excess moisture is one of the most common causes of flooring failure. Before installing any floor covering, test the subfloor using an appropriate moisture testing method to ensure moisture levels are within the manufacturer's recommendations.

If moisture levels are too high, installing a damp proof membrane before continuing may be necessary to protect both the adhesive and the finished floor.

3. Repair Any Damage

Before laying any floor covering, repair cracks, holes and damaged areas to create a solid, stable base. Using the correct repair product will help prevent imperfections from transferring through to the finished floor and reduce the risk of future flooring failures.

For repairing damaged concrete and filling imperfections, Kelmore Feather is an excellent choice. This rapid-setting smoothing and patch repair compound is ideal for filling minor surface defects and feather edging before applying a levelling compound.

Once repairs have been completed, allow the surface to cure before moving on to the next stage

4. Level the Subfloor

A smooth, level subfloor is essential for achieving a professional finish, particularly when installing LVT, vinyl and other resilient floor coverings.

Kelmore offers a range of levelling compounds to suit different applications:

LevelMore Pro – A high-performance smoothing compound suitable for most commercial and residential installations.

LevelMore Contract – An economical option for general-purpose floor preparation.

LevelMore Absolute 30 – Designed for thicker applications where additional build-up is required.

Selecting the correct levelling compound will help create a flat, even surface and provide the ideal base for your chosen floor covering.

5. Choose the Right Adhesive

With your subfloor fully prepared, the final step is selecting the correct flooring adhesive. Choosing an adhesive that's designed for your floor covering is essential for achieving a secure bond and long-lasting installation.

Ardex offers a comprehensive range of adhesives for almost every flooring application:

Ardex  AF 145 – Ideal for LVT, vinyl tiles and vinyl planks.

Ardex AF 165 – Suitable for vinyl sheet and textile floor coverings.

Ardex AF 175 – Designed for LVT installations exposed to high temperatures or direct sunlight.

Ardex AF 2365 – A versatile universal adhesive for a wide range of floor coverings.

Ardex AF 2575 Plus – Developed for rubber flooring and specialist installations.

Selecting the correct adhesive for your flooring type helps improve bond strength, minimise movement and ensure a professional finish that lasts.

Final Thoughts

Preparing your subfloor properly is one of the most important stages of any flooring installation. By inspecting the surface, checking moisture levels, carrying out any necessary repairs and creating a smooth, level base, you'll give your flooring the best possible start.

The final step is choosing an adhesive that's designed for your flooring type. At Floormart, we stock a comprehensive range of Ardex flooring adhesives, providing trusted solutions for LVT, vinyl, carpet, rubber and specialist floor coverings. Explore the Ardex adhesive range to find the right product for your next installation.