Before you start laying new flooring, you need to prepare the subfloor. Floor preparation is a key step, whether you’re installing laminate flooring, vinyl flooring or carpet. The subfloor affects the level and longevity of anything you lay on top, so make sure you follow these steps.

What is subflooring, and why does it need preparation?

Subflooring is the surface under the flooring, which is usually either concrete or wooden floorboards.
Before you can lay any flooring on top of the subfloor, you need to make sure that it is smooth and level. The subfloor also needs to be intact, with no cracks or loose floorboards. You can lay laminate or vinyl on top of hard flooring, like tiles or linoleum, if there are not too many irregularities.

Tools for subfloor prep include:

• Floor Scrapers
• Screed trowels
• Trimming Knives
• Floor brush or vacuum cleaner
• Warm water and detergent
• Filler for your subfloor
• Sandpaper or electric sander
• Spirit level
• Moisture meter
• Screed and primer (if applicable)
• LVT underlay (if applicable)

Browse Floor Preparation Tools

How To Prepare Subfloor For Laminate and Vinyl Flooring

These instructions should help you understand how to prepare a floor for vinyl or laminate flooring. You should plan for delays, in case subfloor repairs are more drastic than expected and require drying time.

1. Remove Current Flooring

Remove any carpet, vinyl, or laminate from the floor. The best way to do this is to start in one corner.

How to remove carpet: Use pliers to lift the corner until you can grip the edge. Pull along one edge of the room. Work your way along all the edges, then roll up the carpet from one side of the room to the other.

How to remove vinyl: cut the vinyl into strips with a utility knife. Use a heat gun to soften the adhesive under the vinyl, and use a scraper to lift the material off the floor. Remove the remaining adhesive from the floor with a scraper. You may need adhesive remover to help with this.

How to remove laminate: start by removing skirting boards as below, then use a crowbar to remove transition strips from the thresholds between rooms. You will need to replace these with new transition strips if you are laying new laminate.
Slide the end of the flat bar into the space revealed by the transition strip and separate it from the next board. Once you’ve removed the first row, you can slide the rest of the boards away more easily.

2. Remove Skirting If Needed

If the old flooring is held down by skirting, you will need to remove skirting boards. To do this, place the sharp end of a chisel at the top of the skirting. Use a hammer to gently tap the chisel into the gap between the board and wall. Once it is in the gap, lever the chisel to prise the board away from the wall.
Carefully pull out any nails left with the claw of your hammer. Mark each board and the wall so you can replace them correctly later.

3. Look For And Repair Any Damage

Once your old flooring is cleared, inspect the subfloor for any irregularities. Debris, cracks, depressions and lumps can affect the way your new floor will sit, so they will need to be fixed. Any depressions deeper than 2mm in a 1m area should be repaired.

• Remove any nails that stick up.
• Use an appropriate filler for minor damage to wood and concrete.
• Significant cracks may need replacing.
• Sand or grind down any bumps until level.
• Use a spirit level to check that the floor is even throughout the room.
• Lay screed to fill any major depressions in concrete or to cover major eruptions that can’t be removed by sanding.

Make sure any filler, screed or new concrete is fully dry before starting to lay new flooring. Any screed deeper than 3mm should dry for 24 to 48 hours before walking on it to avoid creating new depressions. Where possible, try to let your screed dry for at least 28 days before applying vinyl for optimal results. In a pinch, seven days should be long enough.

To prepare a floor for carpet installation, there is less pressure at this stage. There is no adhesive to apply, and any small gaps can be disguised by the underlay. Repair cracks and broken floorboards, sweep or vacuum the floor, and you’re ready to start.

4. Clean The Subfloor

Clean any dust and debris from the subfloor with a brush or vacuum cleaner. Then wash the floor from edge to edge with warm water and detergent to remove any remaining adhesive residue.
Any remaining dust or dirt will make the new floor’s adhesive ineffective.
Let the floor dry completely before continuing.

5. Test Moisture Levels

Before installing new flooring, it’s important to make sure moisture levels are low enough, using a moisture meter.