An underlayment is a thin layer of material sandwiched between two other materials.
Floor with low spot wood.
Mix the compound as directed on the package then pour it onto the low spots in the floor.
Fill cracks or major voids with wood putty or a self leveling compound.
Repair low spots in wood or concrete floors and clean them use an underlayment floor leveler or floor patch product to fix low spots in a wood or concrete subfloor.
If the uneven floor is due to floor joists that have warped or twisted over time or were incorrectly installed the only way to level the floor is to remove the subflooring and shim the joists.
It s used to help insulate absorb sound and reduce wear on your floor.
Use a trowel to spread the material then allow it to dry before proceeding.
Use a mixture designed for wood subfloors.
Use deck screws or ring shank nails set into the floor joists to secure loose or squeaking pieces of wood subfloor material.