When building a storage shed it good to know which types of plywood for sheds will be the best solution for your building materials. After all you’re going to need some type of exterior sheeting for your shed.
In this article I’m going to look at the various types of plywood sheeting that you need for the shed floor, walls and roof. There are other options such as pressure treated plywood, OSB that you can use on your sheds exterior.
What is The Best Plywood for Shed Floor?
There are a few types of plywood for shed floors, from 5/8 inch t/g standard sheeting, OSB types and pressure treated plywood. The most common is the 5/8 inch t/g plywood that is typically used in home framing and is considered a sub-floor material. This means it provides strength but will need to be covered with finished flooring.
Because you’re using the plywood in a shed you’re not going to be using another type of flooring over top of it. While the 5/8 inch and OSB will work, I recommend you use 3/4 inch pressure treated plywood. Pressure treated plywood can handle wet conditions that are common in a storage shed, it will also last the life of the shed, and I like to add solid blocking along the end where the sheets meet between the floor joists.
Can I Use Dimension Lumber For a Shed Floor?
Dimension lumber would be 1×4, 1×6, 2×4, and 2×6, up to 2×12 and there’s the 1 inch 1×6 deck wood. If you have some boards you can use them for the floor, but it’s going to be a lot more work, and usually the boards are twisted and different thickness if there used.
The other issue with dimension lumber is the large number of joints which can let in dust and insects and many of the boards have knots in them and over time some of the knots will fall out making a perfect entrance for mice to get into your shed. I don’t recommend you use dimension lumber for your shed floor unless you’re going to cover it with finished floor.
Which Type of Plywood Material is Best?
Softwood Plywood…The most common made plywood is softwood, which is constructed from layers of softwoods and glued together. The veneer is layered at right angles as each layer is applied and glued; this process makes the plywood much stronger than a piece of dimension wood.
Marine Grade Plywood… Used mostly in boats and the layers are glued with waterproof glue which makes it very durable, it high cost means it doesn’t get used much in shed construction.
Particle Board… Very cheap to buy, however it’s made from sawdust and glue and can’t handle moisture, not a good choice for outside.
OSB [Oriented strand board]… Is constructed from chips of wood and glued together its low cost make it a very common building material, however it needs to be protected from moisture.
The softwood made plywood is rated to be as strong as pressure treated plywood of the same size. The softwood can be damaged by water whereas pressure treated plywood is ideal where moisture can be present. Check out my article Is Pressure Treated Plywood Best for a Shed Floor? to see if pressure treated plywood is an option.
Of all the plywood’s pressure treated is the ideal choice for use as a flooring material for a storage shed. If you need a stronger floor than use the CDX pressure treated plywood.
What’s The Best Plywood For Shed Walls?
The sheeting on the walls of the shed provides structural strength to the shed and also provides a good backing to attach the exterior finishing material. Many homes are built with OSB wall sheeting and many are also built using plywood. I build all my sheds with ½ plywood which give them great strength and excellent backing for the finish material.
Cost wise where I live ½ inch plywood is about the same as OSB. If you wanting to save a few bucks you can use 1/2/inch CDX rated plywood for the wall sheeting which gives you the option to simple paint it or apply a exterior finish to it depending on what your plans are.
If you’re going to be finishing the exterior of your shed than use the 1/2 inch plywood so it can hold the finish better. If you’re going to be applying a stain or paint you can use the 3/8 inch plywood.
Plywood should be covered of panted/stained as soon as possible so it’s not damaged by the elements. Plywood used for the wall sheeting needs to be the exterior grade, this type of plywood is constructed using waterproof glue and can handle the elements much better.
What Plywood is Best For Shed Roofs?
There are some things to consider when choosing what type of plywood to use on the roof:
First… What is the slope of the roof? If it’s steep or shallow will affect how well water and snow will slide off.
Second… Snow load in the area you live, they may be building codes in place to make sure your roof will be able to deal with the snow loads.
Third… Rafter spacing, are your rafters or trusses going to be 24 inches on center or 16 inches on center.
Fourth… Type of roofing material you’re going to be using. If your using metal roofing there’s usually not any roof sheeting used, instead you would strap the roof with 1x4s or 2x4s and then attach the metal roofing to the strapping.
If you’re going to be using shingles [asphalt/fiberglass or cedar] and if you’re going to be using simple roll roofing then you’re going to need to sheet the roof with plywood. I would use ½ plywood, if the rafters are more than 16 inches on center you’ll need to use h-clips between the rafters on the joints; this strengthens the plywood so there’s no weakness along the joint line.
If you’re in a heavy snow load area I would recommend you frame your rafters or trusses at 16 inches on center and use 5/8 t/g plywood sheeting if the slope of the roof is over 4/12. I would recommend you use ¾ inch plywood sheeting if the slope is less than 4/12. It’s better to spend a few more dollars on thicker plywood on the roof to ensure you’re not going to have problems.
How to Cut Plywood
You can cut plywood with a circular saw, table saw, jigsaw and the old fashioned way using a handsaw. The most common method is using a circular saw; you’ll need an extension cord, circular saw, tape measure, pencil, straight edge or chalk line, saw horses and a couple pieces of 2x4s 8 feet long. You should also have a handsaw to finish off the cuts if you cutting out for windows.
Set up the saw horses about 6 feet apart and lay the 2 pieces of 2x4s on top and then lay your sheet of plywood on top the 2x4s, by cutting with the 2x4s under the plywood you’ll not have to deal with binding and pieces falling off during cutting.
Measure and mark the plywood to the size you want to cut at both ends and using the straight edge or chalk line make a cutting line. Set you circular so it’s cutting ¼ inch deeper than the thickness of the plywood your cutting. Before cutting make sure the extension cord and saw cord is out of the way from where you’re cutting and wear safety glasses.
For cutting out for window openings you can tack the plywood in place covering the opening and then mark the plywood from the inside and remove the plywood and put back on saw horse to cut out. You can nail the plywood in place and cut it out from the outside, you’ll need to mark the outside first.
When cutting plywood on the wall ALWAYS cut with your circular saw from the top down, NEVER cut from the bottom up. Doing it this way will prevent injury if the saw kicks back. If you not completely certain just mark it and bring it back to the saw horses to cut.
How to Install Plywood On the Floor
Installing plywood to your shed provides needed strength to the structure and provides a good solid floor that will be strong and safe to work on. You’re going to be using pressure treated plywood on the floor. In the example shed I’m using for my articles of 8 foot by 12 foot you’re going to need 3 sheets of 3/4 inch pressure treated plywood.
Begin by adding a row of solid blocking where the joint of the plywood will be, remember you will be installing the plywood across the joists, don’t install plywood with the direction of the joists.
Next line up the 4 x 8 sheet of plywood with the outside edges on 2 sides and tack into place cut one full sheet in half and complete the row of plywood. Begin the other row with the 4 x4 piece and finish second row with a 4 x 8 sheet. Nail or screw the plywood every 6 inches on the end and floor joists, nail or screw the joints every 4 inches.
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You can do this for any plywood your installing… Measure and mark the centers of the floor joists, wall studs and rafters on the plywood and draw a line. This will make all the nails hit the center of the framing and will be really helpful if your using an air nailer.
How to Install Plywood On Shed Walls
There are 2 ways you can sheet the walls on your shed:
First… Is to sheet the walls when there laying down, if you have the extra manpower to lift the walls into place then installing the plywood while walls are laying down is the easiest. Sheet the walls like you would a floor by staggering the joints. Remember to leave a 1/8 inch gap between the sheets, I just use a 3 ¼ inch nail to space the sheet correctly.
Nail or screw the sheeting 8 inches on the studs and screw or nails the joints to 6 inches. You won’t need to use blocking at the 4 foot line. However if the walls are over 10 feet high you’ll need to install a row of blocking at the half way point.
Second… Is to sheet the walls after their framed and in place. Make sure the walls are braced securely and the corners are level. Begin by placing a couple of nails at the bottom place where the bottom of the sheeting will start, I like to measure up 4 feet from the bottom starting and snap a chalk line, then measure down 4 feet to put the nails on the bottom that will hold the sheet in place while your nailing it.
After you’ve installed the first row of sheeting in place move the bottom nails and place them on the top edge of the plywood, this will set the spacing and support the second row of sheeting. Stager the joints and nail or screw the sheet in place at 8 inch intervals into the studs and 6 inch intervals on the joints.
How to Install Plywood On the Roof
Installing plywood on a roof is the most difficult place and depending on the slope of the roof can be more difficult than a lower sloped roof. Make sure you have finished framing the overhangs.
I will set up a scaffold or lay some 2×10 on the ceiling joists and that makes a nice platform to work from the inside of the roof for laying out and installing the first row of plywood. You’ll need some help for installing the plywood on the roof.
Step 1]… Begin by measuring up 4 feet from the bottom of the rafters and mark at both ends, then using your chalk line snap a line across the rafters. Now put in some 3 ¼ inch nails to guide the location of the top edge of the plywood. Depending on the size of your overhang slide the first sheet of plywood into place. Make sure it’s on the center of a rafter and sticking out enough to cover the overhang.
You can either leave the plywood sticking past the overhang and cut off later or you can measure the size of the sheet including the overhang and cut off before installing.
Step 2]… Nail the top edge of the plywood to the rafters, now you can climb up onto the plywood and mark the rafters and nail into place. Nail the plywood every 8 inches and nail every 6 inches on the joints.
Step 3]… Place 2 – 3 ¼ inch nails along the 4 foot edge before installing the rest of the plywood on the first row. Finish installing and nailing the first row of plywood into place.
Step 4]… Measure the second row of plywood and either cut the width on the ground or cut in place. Lay the second row of plywood against the nails you used to guide the first row. Mark and nail the plywood into place and then remove the spacer nails.
Step 5]… Repeat steps 1 thru 4 on the other side of the roof; if your roof is a lean-to just follow the procedure until the roof is sheeted in. Now you’re ready to install your finish roofing material.
How to Fasten Plywood
There are 3 ways to fasten plywood to the framing members… Nails, screws and air staples. Nails are the most common choice when fastening plywood. Screws are used on the floor which helps to prevent squeals; air staples are not normally used for fastening plywood to floor joists.
For fastening plywood to the floor use a 2 ½ inch common nail which has a big head and has good holding power. The other option for floors is 2 to 2 ½ inch deck screws, just be careful not to drive the screws into the plywood too far. This will cause the plywood to stick up around the screw making a ruff finish and a tripping hazard.
The best choice for fastening plywood to the wall studs is 2 to 2 ¼ inch common nails which have good holding power. Air staples are more common for fastening OSB type plywood’s are you can fasten the plywood with an air nailer with 2 or 2 ¼ inch air nails. For roof sheeting use 2 inch or 2 ¼ inch common nails or air nails.
If you’re planning on leaving the plywood on the walls and paint them, then you’ll want to use 2 ¼ inch galvanized common nails. These types of nails wont rust preventing the ugly finish to the painted walls when the rust bleeds thru the paint. Don’t use finishing nails for any sheeting they don’t have much holding power and the plywood will come lose.
That covers the best types of plywood for a storage shed, I have also gone over how to cut and fasten the plywood to the floor, walls and roof rafters. I hope you have found this article helpful, give it a share. Thanks.