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How To Install Carpet Over Plywood

You are probably wondering how to install carpet over plywood. This is right where you need to be. We have researched all about this for you.

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In order to install carpet over plywood, you need staples, a staple gun, and carpet adhesive or tack strips. In either case, you must start out by measuring your room to find the square footage and then you will need to stretch the carpet to the appropriate size of the room.

Keep reading to learn more regarding subfloor and the process of installing carpet. We will also be talking about whether or not carpet can be installed directly onto plywood as well as how thick a plywood floor should be.

Construction Gloves and Utility Knife On Pulled Back Carpet and Pad In Room, How To Install Carpet Over Plywood

Installing Carpet Over Plywood

What Is a Subfloor?

 lay plywood on the floor boards

There are four main layers when it comes to flooring systems. The order goes floor joists, subfloor, underlayment, and then the finished floor. Your floor will not be stable if your subfloor is not in good condition.

A subfloor is the layer of flooring that is laid down after the floor joists are in place. It is installed across the floor joists. Having a subfloor ensures your floor will be strong and sturdy enough to withstand the weight of people and furniture.

When you are ready to lay carpet that means your subfloor is already in place to give you a structurally sound floor. Subfloor is most commonly made of plywood. The other two materials that are used for subflooring are OSB and sometimes particleboard; although particleboard is the least desirable option of the three.

Plywood is the most popular choice for subflooring because it is durable. It is made up of many layers of wood pressed tightly together which results in a structurally sound sheet of plywood.

Plywood is better than OSB flooring for several reasons. Unlike OSB, Plywood does not typically swell when it is wet and it dries out faster than OSB too. Another perk of using Plywood is that it works for all flooring while OSB does not work well with stone or ceramic tile.

When it comes to installing carpet over plywood you have a few options. Most people utilize a staple gun to staple carpet to the subfloor. You need to apply an adhesive made for carpet before you staple the carpet to the plywood to help make sure you end up with flat flooring.

Carpet adhesive works best when it is a spray adhesive. Gorilla glue makes a spray adhesive that works great on almost any surface including wood. You must apply it to both the plywood and the back of the carpet.

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For area rugs, double-sided carpet tape is more convenient. It is easy to use, strong, and much less messy than the process of spreading glue.

Utilizing Tack Strips

Another option is using tack strips. First, you must cut the tack strips to the size of the perimeter of the room. You will need tack strips for the length and width of the room except for the doorway.

When installing carpet on plywood using tack strips you should leave approximately two-thirds of the thickness of your carpet all the way around the edges of the room between the tack strips and the walls. Then attach the tack strips to the plywood subfloor before adding underlayment or carpet padding.

If you decide to use carpet padding it will provide extra insulation. Place the carpet padding all the way to the edges and corners of the tack strips. Stretch the carpet to the tack strips to end up with a flat layer of carpet.

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You can use standard plywood for subflooring. Do not use pressure-treated plywood for this job. It shrinks a little bit while it is drying which causes problems if it is used as a subfloor.

The best choice is 3/4-inch tongue-and-groove plywood. This type interlocks which results in a stable subfloor.

The subfloor has to dry before anything is installed on top of it. After you have placed the tack strips and carpet padding it is time to install the surface or carpet in this case. Fluted subflooring and ring-shanks are best because they do not pull out or loosen in time as much as standard box nails do.

Regardless of the method you use to attach carpet to the subfloor, the carpet needs to be tight and the corners have to be angled correctly.

What goes between subfloor and carpet?

Man removing carpet underlay from a wooden floor.Home improvement project concept

When it comes to the layer between subfloor and carpet it is known as "padding" or underlayment. This middle layer is used for carpeted floors as well as tile and laminate flooring. On the other hand, vinyl can be placed directly onto the subfloor.

Carpet padding is another option for the layer used between subfloor and carpet. Some carpet has foam padding built into it. If you cut your carpet to be oversized you will ensure that you do not come up short if something does not work out right the first time.

It is helpful to prevent your floors from squeaking by placing a layer of building paper between the underlayment and subfloor. Underlayment is made up of a spongy plastic foam material. When you purchase underlayment it will come in a roll because the way it is made is in one long sheet.

Can you put carpet directly on subfloor?

In most cases, the subfloor is made of plywood. You can attach carpet to plywood by way of a staple gun. 9/16-inch staples should be used for this project.

It is imperative that you use the right size staples and the correct spacing. You also have to make sure the staples sink into the plywood fully. Glue is necessary for a flat floor.

If you are using a staple gun to attach your carpet to the subfloor you should insert one staple every four inches all the way around the perimeter of where the carpet is being placed. Whenever it is needed you can use a hammer to sink the staples the rest of the way into the plywood.

How thick should a plywood floor be?

Plywood is used for subflooring as it is easier to install than OSB and it should be at least 5/8-inch thick. When floor joists are farther apart than sixteen inches you should use thicker plywood such as 3/4-inch thick plywood. If your floor joists are sixteen inches apart or less than that 15/32-inch or 1/2-inch thick plywood is okay.

Thinner subflooring like the half-inch plywood can work for low traffic areas too. As for tiles or hardwood, thicker subflooring is best. Keep in mind you have the option to check the housing codes in your local area so that you can make an informed decision.

Subfloor whether it is plywood or OSB is sold in either 4 x 8 or 4 x 12 sheets. Ultimately your best bet is to go with 3/4-inch thick plywood.

How to Identify Damaged Subfloor

There are a few ways to tell your subfloor is damaged. A few of the ways include but are not limited to sagging or uneven floors, cracked tiles, or squeaky floors. Damage can occur over time from the subfloor getting and staying wet.

If the subfloor has gotten wet and not been aired out properly, mold will occur. Having a wet subfloor creates its own problem and can lead to foul odor as well. This is another way to tell it is time to replace your subfloor.

How do you fill gaps in plywood flooring?

There are repair kits for patching floors and leveling floors for underlayment available as well. These repair kits are made with leveling compound. The other option you have is polyurethane subfloor caulk.

It is essential that you fill in any gaps in plywood flooring because buckling will occur otherwise. We are referring to any space within the plywood panel. Gaps can be filled in with a stiff compound by using a trowel and you may want to sand it after it dries completely.

Leveling compound is made of self-leveling concrete. A good example of this patching compound is called Fix-it-All.

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Something important to understand is that some gaps are intentional though. The panels that make up the subfloor should have a space of approximately 1/8-inch around all ends and edges in order to allow room for the expansion that will naturally take place over time.

Conclusion

installer in overalls holding cutter near carpet

The ways you can install carpet over plywood are either by using a staple gun and glue such as spray adhesive or tack strips. Vinyl is an example of flooring that can be put directly on the subfloor while carpet usually has underlayment or padding in between the subfloor and carpet itself.

Be sure you use the correct size staples if you use a staple gun to attach the carpet to plywood and double-check your measurements to avoid not having the necessary amount of carpet cut out and ready for installation.

Before you go check out one or more of the following links about installing carpet:

12 Types Of Flooring And Carpet Trims And Transitions

How Long Should Carpet Installation Take?

What Types Of Carpet Are Easiest To Clean?