Before laying down the flooring for the room you’re working on, it’s absolutely important that you install the correct subfloor first. But what the best type of subfloor might be for one room isn’t necessarily the right type of subfloor for another – it all hinges on what kind of flooring your project entails.

Not only does the subfloor have to work with the flooring to protect it from moisture, but it needs to be able to support the floor as well. The thickness of your subfloor will depend on the construction design of your home, which will be indicated in the house plans.

Subfloor and Ceramic

If you’re laying down ceramic tile for your flooring project, you’re going to need a solid subflooring material. In a newer home that is still vulnerable to settling, ceramic tile can be easily damaged as the house moves. In this case, a ¾ inch thick subfloor of plywood is your best option, with a half inch backer board of either cement or concrete slab.

Subfloor materials that absorb moisture and may expand and contract are not a good option here, since that may actually cause the tile or the grout to crack and lift. Materials included in this ‘don’t use’ list are oriented strand board and any other porous, manufactured boards.

Subfloor and Laminate

Since laminate floors are designed to float, the flooring panel edges will not be attached to your subfloor. If you’re installing the floor correctly, you’ll have a thin, clear plastic sheet underneath the laminate to help it float – and with this, you can use a variety of subfloor materials, such as concrete and wood.

Subfloor and Wood

When installing solid wood flooring, it can easily be nailed to a subfloor of oriented strand board or plywood, unless you’re dealing with a basement subfloor. In that case, you’ll need to go with a highly moisture-resistant subfloor such as radiant heating or simply a different type of flooring that will not promote mold growth. If you absolutely must install a wood floor over a concrete base, your best bet is a subfloor of ¾ plywood or two by fours, with an asphalt felt or polyethylene film vapor barrier underneath.

Subfloor and Carpet

Since carpet can be installed directly over the subfloor, the thickness of the subfloor can vary according to what the house needs. There is no need to compensate for underlay or support an inflexible material, so either plywood or oriented strand board will work best with carpet.

What Subfloor Should Do

Although the correct type of subfloor for each room will vary according to the flooring that the project calls for, the best type of subfloor will perform all the necessary tasks to protect your flooring materials from moisture damage:

– It should protects against moisture seepage
– Lengthen the life of your flooring materials
– Warm your flooring by at least 20-30%
– Potentially provide drainage abilities

Naturally, before you begin installing a new subfloor, you’ll have to make sure that the surface you’re working with is clean and level. Remember, the subfloor that you lay down is the base for your carpet, laminate, linoleum, vinyl, or bamboo, and if you don’t work with the flooring material that you have, the life of your flooring will be drastically reduced.