How to Add an Extra Layer of Plywood Over a Subfloor (Just 5 Steps!)

Your subfloor provides an excellent, level foundation for the flooring of your home. However, many subfloors might not be the ideal surface on which to lay your finished floors. Therefore, adding an extra layer of flooring on top of your subfloor can help create the floor of your dreams!

To add an extra layer of plywood over a subfloor, you will need to clean the floor to ensure there is no dirt and grime. After cleaning, you will install the plywood over the subfloor one sheet at a time. However, you need to make sure the plywood seams are over the subfloor so that it provides adequate stability.

In this article, we will take you through the anatomy of your floor to help give you a better idea of the importance of the plywood placement. Also, we will provide you with the necessary steps to add the plywood to your subfloor.

Related Content: How Much Weight Can Plywood Support? | What Is Underlayment Plywood? | Types Of Plywood | How To Replace Subfloor Under Your Wall

Resting on top of the joists comes the subfloor, the flat surface on which you install all other layers. The subfloor is responsible for holding up all of the things in your home, from people to furniture to the different layers of the floor. If your house has a concrete slab and no joists, then the slab is considered your subfloor.

Subfloors come in various materials, including plywood, oriented strand board (OSB), or planks. The desired thickness of your subfloor depends on what the floor will be supporting and the spacing of the joists.

Rooms with more substantial furniture will need a thicker subfloor. If your joists are spaced between 16 and 19.2 inches apart, you should utilize ¾ inch plywood and OSB. If you space the joists farther apart than that, you will want ⅞ inch plywood and 1 inch OSB.

Underlayment goes on top of the subfloor, and you don’t necessarily need it for structural integrity. However, using the proper underlayment provides a smoother surface for top layer installation. If you are installing a hardwood floor covering, you should utilize a plywood underlayment. Tile and stone require a cement backer board, while laminate needs a thin layer of foam.

Underlayment can reduce the noise of footsteps, provide extra cushion to the floor, and act as a moisture barrier.

Finally, the floor covering goes on top of all other layers and is what you walk on every day. Your floor covering is what is visible to you and your guests. Therefore, there are many styles available to cater to a variety of design preferences.

Floor covering comes in several materials, such as hardwood, tile, carpet, or vinyl. Since this final layer is all about aesthetic appeal, it doesn’t usually add structural support.

Plywood underlayment is a favorite of many people due to its strength and durability. Plywood is highly recommended as an underlayment when your floor requires a smooth and flat surface for installation.

The plywood underlayment helps cover up any dings or imperfections in the subfloor, allowing you to install floor coverings with ease. Plywood underlayment is usually knot-free and comes in lightweight 4×8 sheets with right-angle edges that make it particularly easy to lay.

NOTE: Some plywood consists of one rough side and one smooth side. Always install the smooth side facing upward.

Installing plywood to the existing subfloor is a straightforward job that you can do on your own. In fact, this is a perfect job for anyone who’s looking to get their foot into the door for DIY projects. It’s hard to mess up a project like this. Unless your original subfloor is rotting, then you may want to call a friend to assist you and teach you how to replace the subfloor.

Additionally, you will save hundreds, if not thousands of dollars on paying a carpenter high labor fees by doing this project yourself. The only cost you will have is the cost of the materials as well as any tools you need that you don’t have. Or, of course, there’s always the choice of renting tools too.

If it makes you feel more comfortable, you can always have a specialist come in to check your subfloor first. If it looks sturdy and you’re satisfied, you can take this project on. If not, then perhaps you can pay the contractor to fix the subfloor before venturing on your own to add another layer of plyboard.

You can add a layer between your subfloor and your floor covering, known as an underlayment. This extra layer provides additional support as well as a smooth surface for floor covering installation. Your floor consists of joists, subfloor, underlayment, and floor covering. The first three provide structural support for your house, and the floor covering is purely for aesthetic appeal.

Plywood underlayment is the most common kind of underlayment because it is strong, durable, and you can sand it down to a smooth finish. If you’re looking to install new floors, installing a plywood underlayment can be an easy and fun DIY project!