How to Level a Floor

If you’re gluing the new floor to the subfloor, use a sander to remove oil, wax, paint, adhesives or other materials. Then thoroughly vacuum off dust and debris.

If you have high spots on your wooden subfloor, use wood screws to secure any loose sheets of plywood or boards. Sand down any remaining high spots.

Sanding can make a mess, so cover any air vents or doors with plastic sheeting. You’ll need to wear protective eyewear and a mask. Then begin using a sander on the high spots. Stop frequently and use a level to ensure you’re not sanding too much down. After you’ve addressed the high spots and the subfloor is level, it’s time to clean up. Sweep or use a shop vacuum to pick up all the dust and dirt.

Use a self-leveling underlayment on low spots on wood. Self-leveler is available in powder and pre-mixed forms and creates a flat, smooth surface in flooring projects. The strength of the product is similar to concrete. Self-leveler dries fast, so you need to work quickly. Pour the self-leveler onto the subfloor. Use a trowel to smooth it out. Follow the manufacturer’s directions for your specific product’s application and dry time.

After the self-leveler dries completely, use a level to see if the low spots are gone. If there are any high spots, sand them down. Clean the subfloor using a broom or shop vacuum.

If you have high spots on your concrete subfloor, you’ll need an angle grinder to remove them. An angle grinder emits a lot of concrete dust, so a good respirator and protective eyewear are essential. Using the grinder, remove the high spots from the subfloor. Check them with a level often. After you’re done, clean up using a broom or shop vacuum.

Use a self-leveler on low spots on concrete. Self-leveler creates a flat, smooth surface in flooring projects. Self-leveler dries quickly. Pour the self-leveler onto the subfloor, using a trowel to smooth it out. Follow the manufacturer’s directions for your specific product’s application and dry time.

After the self-leveler dries completely, check that the low spots are gone using a level. Sand down any high spots. Clean up using a broom or shop vacuum.