Subfloor Over Laminate Flooring

Laminate flooring on an uneven subfloor can cause problems and needs to be addressed.

Subfloor over laminate flooring.

From a distance osb flooring may look a little rough and uneven but when you get closer and feel the surface you realize that s just an optical illusion. The floor can have an unlevel subfloor and still have a base for a nice laminate floor. This means that the choice of subfloor i e what you install laminate over needs to provide the right support. Laminate is a fairly thin material and is not forgiving when it comes to grooves dents and ridges.

As with hardwood laminate flooring is best installed on a 3 4 inch thick plywood subfloor. If you have a subfloor that consists of wood on top of concrete you ll need to test both floors. The concrete subfloor must be sufficiently strong to safely support the flooring furniture and people in the room. If the existing subfloor is in poor condition you will need to add a secondary underlayment of thin plywood over the subfloor.

If you have a weak subfloor that flexes up and down when walked on i would recommended adding an additional layer of 3 8 or 1 2 inch thick plywood underlayment glued and screwed down over a 5 8 or. Inspect the moisture level check the moisture level of the subflooring using a moisture meter. There s absolutely no problem laying a laminate floor over osb provided you take all the moisture preventative steps you would take for a plywood subfloor. Check for cracks and crumbling.

Laminate planks snap together and float above a subfloor which means tiny subfloor imperfections are okay although again a level subfloor will help prevent damage. Laminate flooring which can only be installed using the floating method can be installed over a plywood subfloor over the recommended foam pad. A floating floor laminate or locking hardwood shouldn t be installed over a wood subfloor that s adhered to a concrete slab. To level a subfloor for installing laminate follow the directions above to remove high and low spots.

A breathable foam type underlayment is generally used when installing laminate flooring over plywood or osb subfloors. Remember that laminate flooring like swiss krono usa s laminate wood flooring is a floating floor it will expand and contract as temperature and other conditions change. It s a bit confusing but a flat floor can still be slightly out of level and still create a good foundation for a long lasting floor installation. Laminate flooring cannot ever be installed on a subfloor made of carpet or padding.

In most cases you will not want to use a vapor barrier type underlayment when installing laminates on a standard plywood subfloor because wood is a natural material that needs to breathe installing a vapor barrier over this can cause moisture to become.