Let’s admit it. There’s nothing sexy about subfloors. No one looks at a house and says, “That house is great, and did you see those beautiful subfloors?” If they’re installed properly, no one will give them any thought. But if they aren’t, those invisible boards become a major topic of concern. Every time you step on an improperly installed one, that telltale squeak will make you cringe. Shoddy installation is the source of most problems.
Material choice is paramount. There are several options for subfloor material. Using concrete slab as your subfloor is not recommended due to the high potential for moisture to be held within which can then bleed up into your flooring. Plywood is the most used material historically and is resistant to expansion and contraction.
Oriented Strand Board (OSB) is the next step up from plywood. It is denser and more moisture resistant than plywood. Both of these board types can absorb water, however. Absorption can result in swelling at the edges and warping if it becomes wet. The highest grade material is High Performance Panels which are an engineered, enhanced OSB product that resists water absorption.
Fasteners for your subfloor are just as important as the material. In order to get that squeakless subfloor, use high quality fasteners, like SubLoc® PRO SCRAIL®, which are designed to give you a tight hold that will last for years. Fasteners should be installed no more than 12" apart and aligned down the center of the joists. Where edges of the subfloor sheathing meet along a joist, the fasteners should be arranged in such a way that the fasteners in one subfloor sheathing are placed in the center of the space created by the fasteners in the other subfloor sheathing. In other words, when looked at it from above, the fasteners should be no more than 6" apart on alternating sides of the seam. The use of subfloor adhesive is also recommended.
As with most construction projects, the key is to take great care in your material choice and installation. Invest in the highest quality materials, like SubLoc® PRO SCRAIL®, to give your flooring a great foundation. If you don’t install with care, you are wasting your money and time on any flooring you put on top of it. A little extra effort in the beginning ensures that you’ll never have to think about your subfloor again.