Plywood or Drywall?

Since the 1950s or 1960s, most homes built have the interior walls covered with drywall, more correctly known as gypsum board. This relatively inexpensive engineered material was developed as a replacement to plaster and lath walls. It provides a smooth, paintable wall for a fraction of the effort of plaster and lath and once properly finished, textured and painted it really can’t be distinguished from plaster.

Benefits of Drywall

The major impetus for developing drywall was saving cost by reducing the skilled labor needed to finish walls. While taping and finishing drywall still requires a fair degree of skill, it is much less time consuming that nailing up lath strips, applying the cement inter-coating and then floating the plaster on top of that. In the beginning, drywall was slow to gain popularity, seen as a cheapening of the workmanship that was going into the home, but it eventually took hold. Today, it is pretty much the standard means of covering interior walls, although it is not the only way that interior walls of homes and offices can be covered.

osb, board, wall, structure, room, house, drywall, installing, man, worker, ladders
OSB and Drywall, Mindy Georges

Benefits of Plywood

Plywood offers some distinct advantages of drywall and is a good alternative to be considered, especially if one is looking for a warm, natural look. The sterility of drywall doesn’t provide much warmth, whereas wood grain naturally does. So, what are these examples?

Lower weight – Plywood is actually lower weight than a comparable sheet of drywall. A 5/8″ sheet of drywall weighs 2.75 pounds per square feet, while a 5/8″ sheet of plywood weighs from 1.8 to 2.1 pounds, depending on the type of plywood.

Easier installation – Plywood can be used naturally, without the need for taping and finishing. The only finish most people apply is a couple of coats of varnish. If hardwood plywood is used, the grain patterns provide a distinctive and attractive finish, without any fancy painting techniques. Plywood can be attached to the wall with a number of different fasteners, depending on the “look” one is trying to create.

Resisting damage – Plywood is considerably stronger than drywall. You can easily break a drywall wall, either from simple horseplay or from hitting it with a piece of furniture while moving in. Granted, damage to drywall is easier to repair than damage to plywood, but it’s better to not have the damage to worry about. This is especially good for laundry rooms, garages and other “utilitarian” spaces within the home.

Structural strength – If you’ve ever tried hanging a heavy picture or mirror on the wall, you understand how structurally weak drywall is. You really can’t count on the drywall to carry the weight, but must instead find a stud to nail the hanger into. With plywood, you can attach pictures, mirrors or even shelves anywhere, without a risk of the wall breaking or the attachment falling off.

Advantages of Drywall over Plywood

There are two disadvantages to plywood over drywall. The first is cost. Plywood is considerably more expensive than drywall, especially if you are using a cabinet grade hardwood plywood. This is a large part of what has kept plywood from being used more consistently as an interior wall treatment. The other disadvantage is that plywood may not meet the fire-resistance requirements of local building codes. If the building code requires that an interior wall have a one hour fire resistance, as is common between garages and living areas or between adjacent living areas, plywood is not able to provide that. However, a wall built with 5/8″ drywall on both sides does meet that building code requirement. So, if you wanted to use plywood for aesthetic reasons, you would need to mount the plywood over a layer of drywall.

Strengthening Plywood

Plywood is used in a lot of situations where strength is required. Generally speaking, if the strength of the plywood is not required, then other engineered materials are used. However, there are times when plywood alone isn’t strong enough; or, although it might be strong enough, it isn’t stiff enough to meet the need. In those cases, the plywood needs to be reinforced.

Adding structure

The most common way of reinforcing plywood is by adding structure to it. This can either be an edge piece, that drops below the level of the plywood, such as a edge that is used to support the outer edge of a plywood shelf, or it can be structural ribs that are run underneath the plywood. As a general rule of thumb, the farther these ribs extend from the surface of the plywood, the more strength and stiffness they offer to support it. But what do you do in a situation where there isn’t room to put edges and lips below or behind the plywood to support it? Is there another way?

Fiberglass

Yes, plywood can be strengthened by making a plywood and fiberglass composite. This is fairly common for boat decks, where the fiberglass outer shell is backed up by a plywood core or at times even a balsa wood core.

Fiberglass adds a lot of stiffness to the plywood, especially when it coats both sides. The fiberglass resists stretching, which is technically called “tension” that would try to pull the wood fibers slightly apart, allowing the sheet of plywood to bend. In this, it acts in the same way as rebar does, when used in concrete structures.

To reinforce plywood with fiberglass, start with clean wood. It should not be painted or prepped in any way. A slightly rough, unsanded surface is best, as that allows greater adhesion for the fiberglass resin.

Paint a heavy but even coating of fiberglass resin onto the surface of the plywood. This needs to be heavy enough so that it will soak into the fiberglass cloth, but not heavy enough to run and drip. You will need to work quickly, as the fiberglass resin is a two-part, thermoset plastic, that starts to set as soon as you mix it.

bench, seat, desk, wood, room, windows
Bottom side of bench-seat, Sarah D.

Once the surface is wetted, roll out the fiberglass cloth and cover the surface of the plywood, allowing the cloth to extend beyond the edges of the wood. Be careful to avoid any wrinkles in the fiberglass cloth, as well as to keeping it as straight as possible. As you roll it, work out any air pockets that form, so that it lays smooth. Once the resin is “cured” (not necessary dry, but has reached hardness) according to the directions on the can, a second coat of resin should be mixed and painted on to cover the top side of the fiberglass cloth. Alternating layers of resin and cloth can be added until the desired strength is reached.

It is best to coat both sides of the plywood with fiberglass, rather than just one side. While only one side may be seen as the finish side, the opposite side needs to be coated for both strength and to prevent warping. The resin shrinks slightly as it cures, which can cause the plywood to warp towards the side that is being worked on. By alternating sides in the application of the fiberglass, this warping can be avoided. Keep in mind that the true strength in this composite will come from the fiberglass and not the plywood. Therefore, you want to be sure to use enough layers of fiberglass cloth to ensure the strength you need.

Plywood Scarf and Butt Joints

Plywood is useful as both a building material as well as making a wide variety of projects. But what do you do when the project you are working on is larger than a sheet of plywood? In homebuilding, this is dealt with by nailing sheets next to each other, so that the edges of both sheets are on a structural element. But not all projects allow that. Some things, like boat building, require joining the plywood between structural elements (just like slats). They also require that the joint be made in such a way as to turn the plywood structurally into one continuous sheet, as well as providing a smooth surface.

Difference between Scarf and Butt Joints

wood, woodworking, frame, joint, hands, marked
Woodworking frame and box joints, Jordanhill School D&T Dept

There are two ways of doing this, both of which are commonly used in boat building; scarf joints and butt joints. The basic difference is that a butt joint allows the edges of the two pieces of plywood to meet each other and be held together by a third piece of plywood, called a scab. In scarf joining, the ends of the plywood sheets are tapered and then glued together, creating a single piece of plywood that is consistent in thickness. It also retains most of the flexibility of the original plywood.

Making a Butt Joint

Butt joints are considerably easier to do than scarf joints, but have two distinct disadvantages. The first of these is that they reduce the flexibility of the plywood. So, if you are attaching the plywood around a curve, such as might be done on a boat’s hull or when making a receptionist’s desk for a large office, the joint would cause a flat spot. The other disadvantage is that screws are usually used in the butt joint, which will be visible.

To make a butt joint, a butt block or scarf is cut out of the same thickness of plywood that is being attached. It needs to be wide enough to extend a minimum of four inches on either side of the joint. If thin plywood is being joined, a thicker scarf is usually used.

It is only possible to make a butt joint without screws if epoxy adhesives are used. Epoxy is also useful when the plywood does not have a smooth surface finish, as it is excellent for gap filling. However, most butt joints are screwed, as well as glued.

When fasteners are used for butt joints, they are placed about two inches apart and about one inch from both edges. That means at every two inch spacing, across the width of the joint, there are four screws. Two which are one inch from the edges of each piece of plywood being joined, backed up by another two which are one inch from the edge of the scarf block.

In the case of thinner pieces of plywood, especially 1/4″ thick plywood, screws should be used which are long enough so that the major diameter of the screw pierces the back of the plywood. The excess screw length is then cut off with a grinder.

Making a Scarf Joint

Scarf joints require tapering the edges of both pieces of plywood equally and evenly. This makes the scarf joint much harder to accomplish, but it provides a joint that is virtually invisible. The angle of the tapering is 1:12 or 1:10 for plywood under 1/2 inch thick and 1:8 for plywood over 1/2 inch thick. That means that a 1/4″ thick piece of plywood would have a three inch scarf joint.

To cut the taper for the scarf joint, the two pieces of plywood are marked to show the depth of the taper. They are then stacked, with the edge of the top piece aligned with the marking on the bottom piece. Screw or clamp the pieces down to hold them in place while cutting.

The actual cutting of the taper can be accomplished with a hand or power plane or belt sander. Extreme care must be used to keep the cut and angle consistent. Gaps in the finished joint will weaken it. The final cuts should be made with a jointer plane that has a long base, to ensure that the cut is straight and even.

Once the taper is cut, the sheets of plywood can be unclamped and the top one flipped over for gluing. It is a good idea to put a piece of waxed paper under the glue joint, while gluing and clamping, to prevent the plywood from sticking to the bench top. Either epoxy or resorcinol can be used; however, epoxy is preferred for its gap filling properties.

Coat both sides of the joint with the adhesive and overlay them, being careful to align the two pieces of plywood. The joint needs to be clamped while the adhesive is setting. This can be done by clamping it to the bench top with a thick board on top of the joint (use another piece of waxed paper here) or by screwing through the joint, screwing the plywood to the workbench. It is extremely important that equal pressure be applied all the way across the joint. The holes caused by the fasteners can be filled after the adhesive cures.

What to do with Rotten Plywood?

Like all wood products, plywood is subject to decay. This decay is usually caused by wood-eating fungi, which are activated by the presence of water. Wood can also rot due to wood eating insects getting inside the walls of a home. Regardless of the cause, the rotting weakens the structure and must be repaired as soon as you become aware of it.

rotten, wood, cracked
Rotten Wood, Nic

There are two basic ways of repairing rotten plywood, by replacement or by treating it with epoxy-based compounds. The decision usually comes down to one of cost, with larger repairs requiring replacement, rather than repair. The first thing to do is to identify the extent and source of the damage. With rot caused by fungi, this means finding the source of the water which makes it possible for them to eat the wood, not the fungi itself. Without moisture, the fungi become dormant and will not damage the wood. Keep in mind that water may enter the structure far from where it actually causes the damage. Water can run down roof trusses or other members for a considerable distance, once it gains access to the home.

Repairing Large Damaged Areas

For large damaged areas, the entire area of the damage will need to be exposed. This may require the removal of siding or roof shingles. Be sure to find the full extent of the damage, so that it can all be replaced. Plywood replaced in this manner must be cut so that the edges can be attached to roof trusses or studs in the walls.
Take care in removal of roofing shingles or siding to expose damage. You will want to reuse these, so that your home looks consistent when the repair is finished. Pry the edge up around nail, pulling the nail free of the shingle or siding. By avoiding ripping or breaking the materials, you will be able to reattach them.
Once the damaged area is revealed, it can be cut out and a new piece cut to replace it. Be sure to use the same thickness of new material, as that being removed, so that the siding or roofing can sit flat.

Repairing Small Damaged Areas

The edges of plywood are especially susceptible to rotting, as the water will wick up the end grain of the wood. Therefore, it is not unusual to need to make repairs to the edges of plywood structures, even though the rest of the structure is in good shape. In this case, it is necessary to remove any paint and sealer applied to the wood, so that the wood itself is exposed. Repair is accomplished through the use of epoxy penetrants and epoxy filler. Epoxy penetrants are two-part low viscosity epoxies, formulated for maximum penetration. They have a long working time, allowing them to be brushed and rolled into all the crevices of the wood. From there, they will wick into any open pores, cracks or fissures, totally coating the exposed wood. This seals and strengthens the wood, actually making it stronger than it originally was. Once the epoxy penetrant has been applied and allowed to cure, epoxy fillers can be used to restore any rotted away areas of the wood, returning the appearance to new. This is especially useful in areas where ends of the plywood have rotten away, leaving gaps between pieces of on an edge. The filler also works as an adhesive, when used for connecting additional pieces of wood.

Finishing the Repair

In either case, it is important to properly finish the repaired structure, whether by reapplying shingles or painting the structure. The purpose of paint in architecture is not so much to provide beauty, as to provide a waterproof covering for the materials used. As a waterproof coating, it is important to apply enough paint, or enough coatings of paint, to totally fill the surface.

What Sticks to Plywood

Plywood is used for making many different things, from furniture to homes. In many cases, the plywood itself is not left exposed, but used as a substrate, providing structural strength and a flat surface to adhere the finish materials to. But how well those materials adhere to the plywood may not be as good as we like.
There are several things that can get in the way of adhesives or mastics sticking to the surface of the plywood. But basically, they break down into a few categories:

Texture – Most plywood, other than luan and cabinet grade plywood does not provide a totally smooth surface. This causes problems with some things, like vinyl lettering, which need full surface contact with the substrate to adhere well. Solving this problem requires filling the surface of the plywood and sanding it smooth.

Moisture – Plywood direct from the mill often contains too high a moisture content to guarantee good adhesion. This is easily solved by allowing the plywood to dry to a moisture content of 12 percent, before applying the finish material.

Porosity – Wood in general provides a porous surface. Since most plywood is made of soft woods, the surface is even more porous than hardwood plywood would be. This causes the wetting agents of the adhesive to soak into the surface of the wood, reducing the effectiveness of the adhesive.

Chemicals – In the case of pressure treated plywood, the chemicals that the plywood is treated with cause adhesion problems. Washing the plywood with soap and water and then allowing it to dry for a couple of weeks, before painting, will eliminate this problem.

Flexibility – If too thin a piece of plywood is used as a substrate, it may flex from the weight of people walking on it, causing cracking in adhesive. This problem is especially prevalent when installing ceramic tile. It is always necessary to ensure that a sufficiently thick piece of plywood is used to provide rigidity.

Using primer-sealer

In most cases, plywood should be sealed with a quality primer-sealer before applying any other finish material to the plywood. The primer-sealer eliminates the problem of porosity and the chemicals from pressure treated wood, providing a good surface for adhesives to stick to. The one great exception to this would be when finishing hardwood plywood in furniture and cabinets.

Tiles

When installing ceramic tile over plywood, always use a pre-mixed flexible based adhesive for the tile, not the type that you mix in a tub on site. These are rigid adhesives, which will not survive the normal flexion of the plywood.

Vinyl tiles offer a different problem than ceramic tiles. They are naturally flexible, so they don’t have any problem with cracking when the plywood flexes. The problem with them is gaining good adhesion. If the substrate is an exterior grade plywood, then a thin layer of finish plywood should be applied, before the vinyl tile. One-quarter inch of “A” finished plywood (not luan) will provide an excellent substrate.
Prime this thin layer of plywood before installing the tile, allowing the primer to dry fully. Vinyl tile should always be rolled with a 75 or 100 pound roller after installing, to ensure full contact between the adhesive and the substrate.

Tapes

Even tapes have a problem sticking effectively to plywood, due to the same problems of texture and moisture. There are some tapes, specifically, those designed for rough surfaces, which work well with plywood. Gorilla brand and 3M both produce duct tapes that are specifically designed for use with rough surfaces.

Repairing Plywood

While plywood is an amazingly strong engineered material, it is not impervious to damage. It would be nice if it was, but that’s just not in the cards. Rather, we need to be ready to repair plywood that has been damaged, especially when it has been damaged in a critical area.
There are a number of different types of damage that plywood can incur, but I’m specifically referring to dents, surface cracks and bubbles. Water damage, which attacks the edges of the plywood first, generally requires replacement of the piece (although reinforcement is possible in some cases). Cracks that go all the way through the plywood are virtually impossible, due to the way plywood is made. The next layer of veneer would check the crack, regardless of how seriously the surface was cracked. Major damage, where a piece of plywood is broken pretty much always requires replacement as well.

fixing, making, repair, wood, floor
On-going wood repair, Cesar Harada

Dealing with Bubbles

Bubbles form in plywood when there is a localized failure of the adhesive used to attach the layers of veneer together. Moisture enters into the wood through an unfinished side or through pinholes in the finish and dampens the surface veneer, causing it to expand. As the wood seeks space in which to expand, the bubble is formed.
Since the bubble is only in the surface veneer, it does not destroy the structural integrity of the plywood or what has been made out of it. However, it can expand or the bubbled veneer layer can begin to break if not taken care of. In boats and other structures that are subject to water, repairs should be accomplished as soon as possible.
The delaminated veneer of the bubble needs to be removed from the plywood in order to effect repairs. This is best done by cutting around the edges with a utility knife or chisel, cutting out an area slightly larger than the bubble itself. Be careful as you cut, so as to not damage the veneer layer beneath. Allow the area to dry, before filling the dent left by removing the outer layer of veneer.

Repairing Dents and Cracks

Dents, surface cracks and the indentations left by bubbles can be filled with high-solids epoxy or epoxy putty. You should always slightly overfill the indentation, as the epoxy will shrink slightly while setting. Once set, the epoxy can be sanded, just as if it were wood. Please note though, that it cuts a bit slower than wood, so if you are not careful, you will take more material off from the plywood around the repair than in the repair itself. As long as the sander is sitting flat on the surface, this should not be a problem.
Some people are satisfied with the finish that they are able to achieve by simply filling the indentation with epoxy and sanding it. However, on larger indentations, such as those from bubbles, a layer of fiberglass cloth should be put over the repair to help it blend with the surrounding surface. This layer of cloth can either be attached with epoxy or with fiberglass resin. Epoxy is more flexible, so it will resist delamination caused by flexion better.

Paint the epoxy onto the repair area, place the fiberglass cloth on it, sticking it down and then cover it with another layer of epoxy. Once cured, the epoxy and fiberglass cloth should be sanded, feathering it out to blend with the adjacent surface. Finish the repair to match the plywood’s original finish.

Flattening Warped Plywood

Anyone who has had plywood sitting around their garage or workshop for more than a few days knows about the problems of warped plywood. It seems that just about any sheet of plywood is likely to bow or warp, even if stored the “right way.” Once bowed, it’s hard to work with and at times needs to be replaced, as it can’t be used for its original intent. However, it is possible to straighten warped plywood and use it, just as if nothing had happened to it. Lumber core plywood is worse for this than veneer core, so if you are not going to use the plywood immediately, you’re better off avoiding lumber core plywood. It is also harder to flatten than veneer core, with a greater chance of the plywood breaking during the flattening process.

Why does plywood wrap?

Warping and cupping in plywood is caused by a combination of moisture and heat. If you were to measure the moisture content of the outer veneer on both sides, you’d find that the concave side has a considerably lower moisture content than the convex side. That difference in moisture is what is causing the bow or warp, regardless of how it happened. This can come about from plywood sitting in the sun or sitting somewhere where there is excessive moisture. The sun causes moisture to leave the wood, while excessive humidity will naturally be absorbed by the wood grain itself.

bent, warped, bowed, wood, sheets, brown
Bent plywood, Kevin Saff

Generally speaking, the way that the board was laid allowed one side to be exposed to moisture or heat, while the other side was covered. In cases where both sides are covered equally, it is very rare for plywood to bow or warp. In cases where the amount of bow or warp is slight, the plywood can still be used, especially if being attached to a strong structure. The structure itself will hold the plywood straight, allowing the moisture content of the two sides to equalize and the sheet to flatten. Often, bowed plywood can be used for smaller pieces of a project, while the flattest sheets are used for the large ones. Always start cutting with the biggest pieces needed, so that you can pick them out of the best possible sheets.

How to straighten warped plywood?

If there aren’t enough flat sheets for all the big pieces and the structure isn’t strong enough to straighten it, then it will be necessary to straighten the plywood. Straightening the plywood requires balancing the moisture content of the two sides. Once that happens, the wood will be flat.
To do so, wet the concave side of the plywood with a spray bottle or sponge. Then place the sheet with that side down, either directly on a flat concrete driveway or shop floor, or spaced above the floor by furring strips. The furring strips will allow air circulation, helping to prevent mildew and warping to the other direction. Weighing the sheets down with concrete blocks, filled five gallon buckets and other weights can help as well.
The sheet will flatten on its own if left in this condition. If it is left this way in the sun, it will straighten surprisingly quickly, and may even bow the other way, if you are not careful. Keep an eye on the sheet of plywood as you are removing the bow, to ensure that you don’t leave it sitting out too long.

Making a Plywood Chair Mat

If you have an office in your home, you’ve probably run into the problem if having a rolling chair sink into the carpet, becoming stuck and no longer rolling. This can be annoying at the least and make it harder to work at the worst. Office chairs are designed to roll for a reason, so that you can move around as you work, making the best use of your work surface.

The simple answer to this is to buy a chair mat. These plastic mats are supposed to support the chair, allowing it to move around and not get caught in the carpet. For this convenience, the manufacturers of these mats get a pretty penny, much more than you might expect.

laminate, mat, chair, diy
Laminated Chair Mat, John Loo

The second solution is to make your own. There are several ways of making a chair mat out of plywood, which will not only work better than the plastic ones, but look much better too. But the surprising thing is that none of these designs are going to cost as much as the plastic ones, even if you use quality hardwood plywood.
Since the plywood will be supported all the way across its width and won’t have to span any gaps between floor joists, you don’t need to use a very thick piece of plywood. You could actually get away with 1/4″ thick plywood, but I would recommend making it out of 3/8″ thick to ensure longer life.

The basic size of a chair mat is four foot square. However, there are some that are larger, intended for used when a table is being used as a desk. There are also some which have an extension under the well in the desk, allowing the chair to be pulled up close. This can be done with any homemade chair mat, made out of plywood. One other options, which is not as common, but looks very good is to make a chair mat that is round. We’ll look at that as well.

Chair Mat with Linoleum Tile

The simplest way to make a wood chair mat is to buy a four foot square piece of plywood and 16 wood-grained linoleum tiles. Other styles of tiles can be used as well, but you’ll lose that nice wood look.
It is a good idea to round the corners of the plywood to help avoid them snagging on the carpet. This is easily done with a jigsaw and a sander. You can use a can as a template, lining it up with the two sides and marking the cut line on the plywood with a pencil. Do this from the back side, so that there are no visible splinters.

Another good idea for protecting your carpeting is to round over the bottom edges of the plywood with a router and a 1/4″ roundover bit. Be sure to put the right bearing on the bit so that there is no step, but rather a smooth roundover. Sand the cut to remove any splinters sticking up.
The bottom of the plywood should be sanded and sealed with either a paint primer or with varnish. This will help prevent any splinters from forming and getting stuck in the carpet.
Everything up to this point has been done on the back or bottom side of the plywood. Flip it over, so that the face side is showing. Clean off the surface, and stick the 16 linoleum tiles to the top, aligning them so that there are no gaps. This will be the surface that the chair rolls on.

Chair Mat with Wood Flooring

If you want a true wood chair mat, you might want to look at using wood flooring. For this, you’ll want to use pre-finished tongue and groove hardwood flooring. Normally, hardwood flooring is nailed to the subfloor with a special pneumatic nailer. However, the plywood you are using isn’t thick enough for that. So instead, you’re going to glue it.
Prepare the plywood base the same as mentioned above for use with linoleum tile. You’ll also need to prepare the edge pieces of the hardwood floor, by cutting off the tongue and groove from the outer edges of the outer pieces of wood.

Spread wood glue on the first few inches of the plywood’s surface and lay the first piece in place, aligning the edge with the edge of the plywood. Press it down into the glue well to help it stick. Add more glue to the side of that first piece and lay another piece of hardwood flooring, mating the tongue and groove. If you have trouble getting the two to fit together, a scrap piece of the flooring can be used as a punch, placing it on the outer edge and hitting it lightly with a hammer.
Continue adding pieces until the entire mat is covered. Then place weights on top of the hardwood flooring, to clamp the mat together as the wood dries.

Round Hardwood Chair Mat

An even simpler chair mat can be made out of hardwood plywood, without losing any of the beauty of hardwood flooring. At the same time, it can also be made round. To make a large circle for cutting, start by drawing lines from one corner of the plywood to the opposite making an X on the backside of the plywood. This will show you where the center is.

Drive a small nail or tack into the back of the plywood, in the exact center of where the X crosses. Tie a piece of string to this and tie the other end of the string to a pencil, so that the pencil is just short of the edge of the plywood. You can now use this as a giant compass to make a four foot circle on the plywood.
Cut the circle out of the plywood with a jigsaw, working from the back of the plywood to help prevent splintering of the face veneer. Then sand it to remove any irregularities that are created by the cutting. Route and finish the back or bottom side as stated above and apply a couple of coats of flooring varnish to the top side to protect the wood. Be sure to use flooring varnish, as it will provide a harder finish.

Painted Plywood Floors

Painted plywood floors can be beautiful, and depending on the type of plywood and paint you opt for, these floors can help you save quite a bit of money. Whether you’re working on an attic, a play room for your kids, or even a den, dining room, or other living space, you’ll find that painted plywood floors are a practical, stylish choice.

How to Paint a Plywood Floor

One solid color? An interesting check pattern? A muted grey or bright white to open up your space? The options for painting plywood floors are nearly limitless. Before we talk colors and designs, though, let’s go over the basics of how to prep and paint a plywood floor for a smooth, attractive finish.

Tools and Materials

• Patching compound and putty knife

• Palm sander with 120-grit discs

• Dust mask and eye protection

• Wet/dry vacuum (shop vac)

• Mop, barely dampened

• 12-inch roller frame and corresponding roller covers

• Extension pole for roller

• Paintbrushes in various sizes

• Oil-based wood primer, preferably labeled for floors

• Paint, such as porch and floor enamel

• Pencil, stencils, masking tape, and other materials needed to create desired design

• Acrylic, water-based polyurethane, or shellac sealer

• Floor finish applicator for sealer

We recommend getting these tools, abrasives, paints from popular shops like: Amazon, 3M, HarborFreight, HomeDepot, AceHardware, StanleyTools, RedDevil, Sherwin-Williams

Preparing a Plywood Floor to be Painted

Before you get started, clear everything from the room and be sure that the space is well-ventilated. Survey the floor to ensure that the plywood is firmly attached to the floor joists beneath, and tap down any fasteners that are protruding. Once you’ve finished this preliminary step, you’ll be ready to get started.

1. Install plywood if necessary. If painting a plywood subfloor, clean it thoroughly before moving on to the next step. Check to be sure all plywood is in good condition and consider replacing or fixing any pieces that are in bad shape.

2. Fill nail holes and joints between sheets of plywood with patching compound. Don’t worry too much about neatness; you’ll be smoothing everything down when you sand.

3. Once the patching compound has dried, start sanding the floor. Work in small sections, vacuuming up the dust as you go.

4. When you are satisfied with the floor’s texture, vacuum the whole thing.

5. Go over the floor with a mop that has been barely dampened, removing the remainder of the dust. You may have to rinse the mop several times, wringing it out well after each rinse.

6. Ensure the floor is free of dust and completely dry before beginning the next step.

7. Using a paintbrush, cut in the edges of the floor with primer. If you plan to apply baseboard molding when finished, don’t worry about taping off.

8. Use the roller to prime the rest of the floor. Work in sections, beginning at the section furthest from the door and working your way out. This way, you won’t find yourself painted in a corner.

9. Allow the primer to dry per the manufacturer’s instructions. Apply a second coat if needed.

10. Once primer has dried completely, it’s time to begin the painting process. It’s often a good idea to lay down a single coat of light-colored paint before stenciling a pattern. If you are working with contrasting colors, lay down the lighter color first. If working with several colors, you may be better off drawing or stenciling your pattern before laying down any paint.

11. Allow your paint to dry completely between coats and colors. Follow the manufacturer’s instructions regarding sanding between coats.

12. Allow the painted plywood floor to dry completely before applying the sealer. You’ll want to apply two or more coats for a durable finish that lasts.

13. Allow the floor to dry for at least two hours before testing to see if it’s dry. Although you will be able to walk on it in sock-covered feet within a few hours of application, you will want to allow the finish to cure for 24 to 48 hours before bringing in rugs, furniture, and other items.

14. Decorate your room and enjoy!

Colors for Painted Plywood Floors

floor, wood, flooring, paint, white
Painting floor in white, NeroDominus

So, what about colors? Plain white or cream opens up a space, is fuss-free, and is just about foolproof. It’s a good choice for any space.
Other pale colors such as the lightest hues of yellow, green, gray, or even lavender can be nice. Be sure to consider which furnishings, rugs, and art you’ll be using in the room you are painting.
Blue is a nice choice too, whether brilliant and playful or subtle and muted. Be careful though; the darker the color, the smaller your space will appear.
Neutral beige, tan, and coffee colors work well too. The lighter the color, the more open your room will look.
For a more vibrant appearance, try a spicy red or mustard tone. These colors work well in kitchens, studios, and other spaces where creativity reigns supreme.

Patterns to Consider

If you’re considering a pattern or stencil for your painted plywood floor, you’ll find that simple checks or diamonds are easy to lay out. You can swirl the paint to get the look of stone, use an interlocking circle pattern, or stencil on another design that appeals to you.
Last, but not least, remember that you’ll get the best results with high-quality plywood like ACX or Okoume, but you can paint any plywood floor to give your space a quick update at an average cost of under a dollar per square foot. Price will depend largely upon the cost of the materials you choose to use, but you’ll find that even with high-quality plywood and paint, you will ultimately spend less than you would on traditional floor coverings.

Plywood Slats

Plywood slats are a convenient option for building or updating a platform bed. They are also ideal for building, repairing, and updating boats, building a glider for your lawn or porch, and many other applications. Typically sold in sets rather than singly, plywood slats are available in a variety of sizes to suit your needs. Here, we’ll take a look at some of the most popular ways to use this attractive wood product.

wood, slats, wet, water, brown
Wet wooden slats, Martin Kenny

Slats for a Platform Bed

If you’d like to make a bed more comfortable and get rid of an old or unattractive box spring, a platform bed with plywood slats is an excellent option. Slats made with solid wood are often too flexible, making them less supportive and decreasing your comfort level. Plywood slats allow for better air circulation than solid plywood sheets, and they’re much easier to work with.

If you’re making a custom bed frame or refurbishing an antique store find, plywood slats can help you to create a sturdy platform bed that will last for years. Typically pre-sanded for your convenience, they are very easy to install with nails or screws, and in many cases, they can simply be laid across the bedframe. When building, consider adding a center support to give the finished bed better stability, particularly if the bed is larger than twin size.

Slats for Boats

When choosing plywood slats for boats, consider purchasing a quality marine plywood product. Marine plywood slats provide the protection your boat needs, preventing damaging, dangerous exposure to water. In many cases, decks and other elements constructed with plywood slats give your boat added value. If your boat is an inexpensive one that you use rarely, and so long as it is stored in a dry area rather then tied up at a dock, you may be able to use exterior plywood slats instead. When using plywood slats for boats, be sure to check with the vendor or manufacturer to ensure that you use the correct preservatives. Polyester resin, epoxy, fiberglass, or a combination of preservatives will extend the life of your plywood in some cases, preventing rot. Selecting the right product for the job, taking your time, and measuring carefully are the keys to creating a handsome finished product that offers good performance.

Glider Slats

A well-made glider is more than just a place to sit. It offers comfort and durability while adding a wonderful finishing touch to your porch, patio, or lawn. Whether you’re building a new glider or repairing a used one, you’ll find that plywood slats offer the strength and durability to stand up to frequent use. Be sure to give your plywood glider slats at least one coat of a protective waterproof finish before installing them on the glider frame. Once you’ve attached them using screws or other appropriate fasteners, apply one or two more coats of finish, following the manufacturer’s instructions carefully.

Plywood slats can be used to create beautiful wood floors, attractive custom paneling for walls, Adirondack chairs for your porch, special deck chairs to place around your swimming pool, and many other projects. Their beauty and durability, paired with their ease of use make them a fantastic choice for a variety of woodworking applications.