Plywood vs Concrete Subfloor under your hardwood

No matter what your substrate, we are going to make sure your floor is within spec before we install a hard surface flooring. That is 3/16? in 10 feet allowance per the National Wood Flooring Association?s guidelines. If you have a concrete subfloor we use a combination of leveling compound in the low spots and grinding down the high spots to achieve a more level field. We can use these same techniques over a plywood subfloor, but there are other things to consider. If you were planning on nailing the floor, you cannot nail through the leveling compound- so you might need to change your install method. Also, primer must be used under the compound above the plywood- this additional step is an additional cost.

I often see the upstairs plywood subfloors have sagged on either side of the beams. It can be 50 year old homes, it can be only 10 year old homes. It depends on construction. This might be as much as 2 plus inches depth on either side of a beam in a 10? room. This is an enormous leveling project. We cannot pour endless amounts of compound upstairs, it is expensive and heavy. Sometimes we install plywood in the deepest areas then feather it in with leveling compound. We are not trying to get it FLAT, just less bowed so that the floor does not noticeably move under foot.

Leveling issues are something we deal with on almost every single job. They are often costly and they are never what the customer wants to hear. On rare occasions, I can surprise someone with no leveling at all. Most of the time there is some degree of leveling, and we often run into large leveling projects that are much more extensive than the homeowner would have liked. But I find that most people want it done right, you don't want to be disappointed with the floor you spent so much money on because it moves and creaks under foot. We don?t need to go for perfection. Construction is never perfect, but we want a comfortable and stable floor. Unfortunately it is not something that can be detected before the job begins, so leveling is something we must warn our clients about, navigate after the demo work has been done, and work through as a partnership during the project.

Choose a company that you trust will do what is best for you and your home, giving you all the options, and giving you the best advice. Call Geneva Flooring any time to talk about your project, and we will do our best to give you the advice you need, to get the result you are looking for.

Lisa Wells
Owner