Can You Put New Hardwood Floors on Old Hardwood Floors?

Solid Hardwood Flooring

Solid -- or traditional -- hardwood flooring is composed of solid hardwood planks measuring 2 ¼ inch wide and ¾ inch thick. Traditional hardwood floors are most often oak, but other species can be used -- from teak to pine -- depending on how resistant to denting the wood needs to be and the client's budget. Whatever the species, solid planks must be installed over some type of wooden subfloor on or above grade and nailed down -- versus glued, stapled or floated over the existing subfloor. Old hardwood floors work well for this.

Engineered and longstrip plank hardwood flooring go over a hardwood subfloor, but they do not require wooden subfloors of any type, as do solid hardwood planks. Engineered and longstrip hardwood go over virtually any type of subfloor -- including concrete slabs -- as long as you place a moisture barrier between the subfloor and the new hardwood and the subfloor is clean and fairly level. Engineered and longstrip planks can also be placed below grade -- or below ground level.

Because hardwood floors can last a lifetime with proper care and are relatively expensive, the most practical option may be to renovate an old hardwood floor, rather than use it as a subfloor. Do repair work first, such as planing and sanding an uneven floor or fixing warped planks. Then screen and recoat it. Screening grinds down the old finish layers to remove them and recoating is the process of applying a new finish. Renovating even antique hardwood floors in this way can make them shine like new.

In certain cases, damaged hardwood, including hardwood suffering from water damage, can work as a subfloor. Wood naturally expands and contracts as it absorbs and loses moisture, whether it's because to spills, high humidity or a flood. If there is too much water damage, hardwood planks can warp so badly they become unusable as a top floor, but can be repaired sufficiently to use as a subfloor once they are dry. If a damaged hardwood floor can be repaired to the point it is dry, clean, free of mold issues and fairly level, it can be used as a subfloor. Homeowners should consider if it is cheaper to repair the hardwood or rip it out and install a less expensive subfloor, like plywood.