These are typically softwood plywood that has been sanded smooth at the factory, which can save you a step when building furniture. This type of plywood has a thick core of solid wood, sandwiched between thin wood veneers like traditional plywood. The core is typically made of an inexpensive softwood like Douglas fir, with ornamental wood on the outside layers. Exterior plywood is specifically made to withstand the elements. The veneers are held together with water resistant glue, so the layers don't peel apart. It's typically used as exterior sheathing plywood on the outside of a house, such as roof decking.
For thicker decorative plywood without the huge price tag, you may want to consider lumber core plywood. Many of my woodworking plans call for plywood, and I get a lot of questions from readers asking about the types of plywood I use. The type of plywood used on garage storage shelves will be very different than the kind used on a kids bookshelf or a pantry cabinet. Take note that the plywood cutting service of Home Depot isn’t meant to fit your desired size by the inch. That is unless you bring your own tape measure and pencil to do the markings.
C/D grade plywood
It's a cheap option for covering a large area, but I would go with something nicer if you're making something you'll see all the time. OSB is a product somewhat similar to particleboard, but it is made from large thin chips and slivers rather than little splinters. Since the pieces it's made of are more robust, the material itself is also stronger than particleboard. This comes in handy because A - B will be cheaper than straight A. Often it won't matter for your project because people will only be able to see one side of the wood anyway.
Grade A plywood will have a perfectly smooth surface which is good for when you want to stain your project or leave it natural. There will be no knots or imperfections, and both sides will be flawless. This is the most expensive type of plywood, and is usually referred to as cabinet grade plywood.
Furniture or cabinet grade plywood
Take note that just because there’s someone assigned for wood-cutting doesn’t mean you’ll sit around and wait. You should help the person cut the plywood for you. Remember, this is a free service, so a helping hand would be much appreciated. If this free service is made available to wood purchased outside, woodworkers will come lining up to Home Depot. That means everyone can use their cutting tool without buying anything from the store. Not only does marine plywood use weather resistant adhesive, but it can also be made with rot resistant wood.
The major benefit of this material is the perfection of the finished surface. Since it's completely fabricated, you don’t have to worry about any knots or imperfections in your piece. However, there's no wood grain, which can be a problem if you want to stain your finished project. MDF is one of the most common plywood alternatives.
Structural plywood
It is made by mixing ground up wood fibers and sawdust with glue and then pressing this paste into a sheet. Sometimes the outside is covered with a thin layer of melamine so it doesn't need to be finished after assembly. It will be less expensive than other options, because it's a softwood plywood that has knots and imperfections. You can use it for furniture making, but will take a lot more work to make it look nice.
Tropical plywood can be used for outdoor furniture because of its weather resistant properties. I used A-B plywood on my sliding barn door because one side was covered up with wood shims while the other side was just stained. I used the better A side for the back facing into the bathroom, and the B side for the shims. My goal is to teach people how to fix up their homes and furnish them with custom woodworking projects that are perfect for their space. I used OSB for my storage shelves because they were going in our shed and didn't need to look pretty.
Particleboard
The higher the grade, the more flawless the surface will be. Think about how your project will be finished before choosing the plywood. Plus, it's an easier and more cost effective way to cover a larger area. Remember that sometimes one piece of plywood will have two grades.
Sometimes, you will see plywood that has two letter grades. This means that one side of the sheet is grade A and the other side is grade B. So one side will be perfectly smooth and the other side will have patched knot holes.
I'll only use the good stuff on the nicest furniture pieces that rely on precision accuracy without any bowing. First, a log is soaked in water, then it is loaded onto a big machine which shaves the log down into thin sheets - like peeling an apple. These sheets are called “veneer” and they are glued together in opposing directions and pressed to create plywood. What's the difference between types of plywood, or what to look for when buying plywood.
We’re talking about plywood here, so the edges will most likely be rough and uneven. Once you have decided what type of plywood best suits your needs, it's time to go buy it! Here are a few things to watch out for when you're selecting your wood.
Particleboard may be cheaper than plywood, but it is the least durable of all the materials we have discussed. While the sheet goods below aren't technically types of plywood, they can be an adequate substitute in some cases. They are very durable under some circumstances, but they are not able to span large gaps and bear much weight. Whether they can cut it or not depends on the store and your agreement with them. If you’re a regular, they will most likely accommodate.
I have had the experience in one store that they won’t cut less than 12″. If you’re patient, friendly, and not arrogant, the staff will produce accurate cuts. And since I’m a regular, I’ve landed a few discounts before as well.
