What goes beneath your flooring is just as-if not more important than-what goes on top of your flooring. A good subfloor provides a proper base for your flooring, ensuring it doesn’t settle, crack, shift or sag later on down the road. Use this guide to common subflooring solutions and get the most out of your new flooring.
Carpet and Vinyl
These common flooring materials are able to tolerate a simple subfloor because of their flexibility. Spaces as much as 24 inches can accommodate carpet or vinyl flooring with ease. OSB or other plywood laminates are suitable for these products and can be placed as a cheap subflooring. Concrete flooring must be covered with a plastic moisture barrier pad to prevent humidity concerns and moisture problems between the carpet and the concrete slab.
Ceramic and other forms of tile are too heavy to be supported by a weak subfloor. ATSM standards require that a tile floor needs a subfloor joist spacing of no more than 16 inches apart. A good ¾ laminate board topped with a solid ½ inch thick cementious backer board is the only way a tile should be placed on a wood floor.
Tiles can also be placed directly on concrete slabs. A substrate of cork paper can help to prevent shifting tiles over cracked concrete slabs.
Wood flooring is directly nailed to a wood subflooring and needs no special protection or vapor barrier. It can be nailed directly over 24 inch or less on center subfloors. Wood flooring that is placed over concrete needs not only a vapor barrier, but a termite barrier between the concrete and plywood subfloor surfaces.
Engineered wood needs a wood subfloor that has at least 16 inch on center joist layouts. A ¾ inch or greater thickness of plywood must be used. The plywood is then covered with a sheet of laminate foam that adds a layer of moisture protection as well as padding for a softer feel underfoot. Engineered wood can also be placed over concrete, but it needs to have a foam pad for a vapor barrier as well.
This wood product needs a good subfloor because it is so thin. And because it floats on the floor, it needs to have a smooth surface to allow it to move across. When a piece of linoleum is placed over concrete, a simple bond of adhesive is all you need to provide flexibility while still adhering the product to the subfloor. When linoleum is adhered to a wood substrate, it first needs a piece of plastic placed on the subfloor. This provides a smooth surface for the linoleum to adhere to and prevent the woods natural movement from interfering with the linoleums natural movement. The plastic also creates a vapor barrier between the two surfaces.