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What Are the Best Plywood Shelves for a Shed?

plywood shelves

When you’re searching for storage solutions for your shed, shelves are often the first thing that comes to mind. Putting up your own DIY plywood shelves has more than one advantage.

For one thing, you can utilize the interior wall studs and cut your shelving to fit. You can make good use of any odd spaces such as to the sides of the doorway or a back corner, fitting them with shelves.

It’s also a good way to make use of any lumber leftover from your shed build, whether you built it yourself or had it built. That’s a good way to save money. Let’s hope you didn’t just throw it away.

The best plywood shelve is one that will provide the width and length as well as the strength to support whatever you’re going to store on it.

What Kind of Plywood is Used for Shelving?

You need to pay attention to the grade of plywood. If you intend to paint or stain your shelves, some advice using hardwood plywood instead of the common softwood plywood. Of course, this will cost a bit more, and may not be necessary.

The outer surface of plywood is graded from A to D. A has the nicest, smoothest finish and is often used for cabinetry and other interior uses. D is the least favorable grade, featuring a certain allowable number of knotholes and other defects. The better the finish, the more it costs.

The great thing about these grades is that you can have one grade for one side and another grade for the other. This means that you can get plywood rated something like A/C, meaning that you have the smooth A side for painting or staining while saving a bit of money using the cheaper C side on the bottom.

Have you ever wanted to build your own shelving, outdoor sheds, benches, greenhouse, garden shed, and other projects and save $100’s on your cost? Check out Ted’s Woodworking Plans here. You don’t need a big fancy workshop or $1,000’s in tools.

If you live in a humid environment, you might want to consider using exterior-grade plywood. This is pressure-treated with chemicals to withstand moisture. Plywood will swell a bit when it absorbs moisture.

The good thing about plywood is that the moisture is usually spread throughout more evenly, allowing it to evaporate more quickly than some other possible shelving choices such as Oriented Strand Board.

That’s not to say that this type of plywood is waterproof, because it isn’t. However, the pressure treatment will help keep your shelving from being so affected by moisture in the air, which is inevitable at some point if your shed is not heated and cooled.

One caveat to using the exterior grade treated plywood is to take care when you’re cutting it down for shelving. The chemicals infused into the plywood can cause skin irritation when the sawdust comes into contact with the skin.

Of course, you don’t want to inhale any of it either. It would be a good idea to make all your cuts at one time and protect yourself with a dust mask, safety goggles and a long-sleeved shirt.

There is a rather unusual type of plywood that is often used for long shelves. If you plan to run shelves the length of a sizable shed, you might want to take a look at lumber-core plywood.

It features a core of actual lumber to give the wood further strength. Of course, it will cost a bit more, but if you’re going to run three or four shelves twelve feet long or more, it might be worth your while just so that you don’t have to worry about how the shelves are holding up in the future. If your considering plastic shelving units, get more information in my article Are Plastic Shelving Units Strong Enough for a Shed?

How Thick Should Plywood Shelves Be?

This should be your first consideration when thinking about plywood shelves. It’s generally recommended to use plywood 3/4″ to 5/8″ thick. You don’t want to use thinner plywood since you want your shelves to hold weight and hold it for a long time. Thinner shelves will eventually sag under the weight.

In addition, thinner shelves will require more bracing closer together to hold the weight. You may save a bit of money on thinner plywood, but it will cost you more in materials and labor time to make it practical. Check out my article Is it Cheaper to Build or Buy Storage Shed Shelving? if your wanting to build your own plywood shelving.

How Far Can a Plywood Shelf Span?

For 3/4-inch plywood, the longest span recommended is 36 inches. If you use thinner plywood, this span lessens quite a bit, down to 24 inches for 1/2-inch plywood. Remember that you are asking your shelves to do a job and do it for a long time. Let’s face it, some things may just stay on the shelves for a few years before you know it.

Not only is the actual weight itself that you will be putting on the shelves a consideration, but the fact that it will stay there constantly for a long span of time. Your shelving has to not only hold the weight but keep holding it without sagging after a few years. Check out my article Messy to Organized – Installing Plywood Shelves in Your Shed for more information on plywood shelving and how to make them stronger.

What is Better for Shelves MDF or Plywood?

In case you haven’t heard of MDF, the letters stand for Medium-Density Fiberboard. It makes use of all the shavings and sawdust left over from industrial wood milling. These are collected during the milling process and dried thoroughly. These fibers are mixed with was and resin and formed into panels.

The panels are then compressed with high heat and pressure, causing them to become rigid with a hard outer shell. Finally, the product is sanded down to create a very smooth finish. The panels come in 1/2-inch or 3/4-inch thicknesses. They also can be further treated and are marked with colors to indicate their additional qualities.

Have you ever wanted to build your own shelving, outdoor sheds, benches, greenhouse, garden shed, and other projects and save $100’s on your cost? Check out Ted’s Woodworking Plans here. You don’t need a big fancy workshop or $1,000’s in tools.

MDF that’s treated with a fire retardant is typically marked with red or blue, while green indicates some moisture-resistant qualities.

Below are some pros and cons of both plywood shelves and MDF compared to each other.

Plywood: Pros – Plywood is usually less affected by moisture, and is not as likely to split when fasteners are inserted into the edges. Plywood also holds more weight when comparing the same size shelves. It’s available in different wood species if you have a preference. It’s also available with no formaldehyde or other Volatile Organic Compounds or VOCs.

Cons – Plywood is more expensive and it’s harder to make smooth cuts and edges compared to MDF. It’s harder to cut smoothly and the layers are visible on the edges. It does develop splinters, especially when you’re cutting it. If you don’t get formaldehyde-free plywood, you need to take care when cutting, doing so outside or in a well-ventilated area.

MDF: Pros – MDF is easier to work with than plywood in general. It usually costs less than plywood and there is no wood grain to consider. The smooth surface won’t produce splinters and is easy to paint.


Cons – The density of the product makes it pretty heavy, and you may need a helper to handle full-sized sheets. In addition, you need to take care not to bang the corners as they can be damaged. Because of the hard outer surface, you need to drill a countersink recess before using screws to prevent problems. MDF also won’t handle the same weight loads as plywood.

Extra care must be taken when cutting, as MDF produces very fine, powdery dust that floats through the air. With the urea-formaldehyde that oozes from the MDF unless it’s fully sealed, it’s best to cut it outside if possible.

If not, be sure to cut in a well-ventilated area and use a respirator if possible. Cover anything that you don’t want the dust to settle on and use a vacuum to get up the dust when you’re done. Wear clothing that you can easily put into the washer when you’re done.

How Long Can Plywood Shelves be Without Sagging?

As has been stated, the longest span for 3/4-inch plywood shelving should be 36 inches. That being said, you also need to think about the weight of what you plan to put there. Cans of leftover paint or heavy machine parts may put more weight on the shelving than you think. It’s better to have bracing at shorter intervals than you think you may need to remove any doubt as to how much the shelves can bear.

Does it Matter Which Way You Cut Plywood for Shelves?

You may think that this doesn’t matter, as plywood is made of several layers of wood veneer that are laid perpendicularly to each other in alternate plies. However, it’s recommended that the outer layers, which will run in the same direction, be run lengthwise for shelving.

The smoother side should be on top. This will facilitate using paint or stain on the shelves. In addition, the smoother side is less likely to develop splinters as you move items around on the shelves. Another tip is that when cutting the plywood to size, you need to make sure that the saw blade exits the sheet on the good side. This means that when using a miter or circular saw, cut the sheets with the better side face down. If you’re using a table saw, the good side should be up.

How Much Weight Can Plywood Shelves Hold?

Generally, a two-foot span of 3/4-inch, five-ply plywood will hold about 170 lbs. per square foot. In more understandable terms, a 12 x 36 shelf will hold 50 pounds easily. Just for comparison purposes, if the shelf were only made of 1/4-inch plywood, the same span shelf would only hold about five pounds before it starts to sag. Check out my article Freestanding Shelving Units vs Wall Mounted Shelving Units for Storage to see which ones can hold the most weight.


If you only want a few short shelves or plan to build a small corner shelf unit, you can use MDF if you prefer. Adding an additional lengthwise brace underneath is also a good idea. For longer shelves, especially those holding heavy items, plywood is better. Basically, your choice comes down to your needs and preferences. If your a beginner and need some ideas for shelving, check out my article 6 Shed Shelving Ideas for Beginners.