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If you did any home improvement during the COVID-19 pandemic of 2020 and 2021, you experienced the extreme inflation of plywood products. Marine plywood is a specialized type of plywood and it saw some extreme inflation as well as major shortages.
This meant that anybody working on a boat needed to find a marine plywood alternative, and fast! Fortunately, there are many alternatives but there are 4 that are easy to find on a regular basis.
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4 Easy to Find Marine Plywood Alternatives
When you are looking for alternative materials, you need to choose something that you can actually get your hands on. Sure, you could choose a product that is cost effective or incredibly similar. But if you can’t get ahold of the marine plywood alternative, it isn’t going to do you a bit of good.
Moisture Resistance Medium Density Fiberboard (MDF)
First and foremost, this product is a moisture resistant MDF, not a standard MDF. Standard MDF sheets will swell quickly and terribly if moisture hits them. However, the moisture resistant version is simple to use interchangeably with marine plywood.
The major problem with choosing moisture resistant MDF as an alternative to marine plywood is that it’s difficult to find and easy to confuse with standard MDF. Be very clear when you are ordering your lumber to specify that you need the moisture resistant version.
Exterior Grade Plywood
Exterior grade plywood typically looks almost identical to other types of plywood. However, it is made using specific glues that hold the plies together. These glues are rated for the variation in weather and moisture that being outside brings.
For sure, exterior grade plywood is much better equipped as a marine plywood alternative than most plywoods. It resists rot and delamination better than any interior grade plywood. Basic exterior grade plywood is also inexpensive and every home improvement store has some.
Fiber Cement Board
An excellent alternative to marine plywood is fiber cement board. This product is actually made from cement that is reinforced with fibers running through it. Because of its makeup, fiber cement board is basically rot-proof.
The downside to fiber cement board as a marine plywood alternative is that it can be expensive and hard to find in stock in sheets. The place you will find it usually is back by the tile or with the siding.
Birch plywood is a last ditch alternative to marine plywood. Birch comes in many different grades of plywood and you want to make sure that you are selecting an inexpensive version. Look for a C or even a D grade.
You don’t need to pay for fancier birch plywood because to make this plywood a good marine plywood alternative will require you to cover it anyway. Birch plywood is typically easy to find though and it doesn’t have voids or holes like other plywood options.
What is Marine Plywood
Marine plywood is a very specific type of plywood used mainly in building boats. It works well for this application because it has adhesives that can withstand high moisture environments. Marine plywood is typically made with smaller voids between the plies as well.
This helps keep moisture out from between the layers and helps the plywood last longer. The only reliable way to identify marine plywood is to find the stamp on the side of the plywood that says “marine.” Without that stamp, this plywood will look identical to radiata pine or birch plywood.
How Can You DIY and Waterproof Regular Plywood
If you do have to use a marine plywood alternative, you may have to help it last longer by covering it and waterproofing it. There are several ways to do this, fortunately. Make sure if you paint something on that all six sides are covered completely.
One of the simplest methods of waterproofing plywood is to use porch and floor paint. Make sure to apply several coats and this method will stand up to light to medium foot traffic and some equipment traffic for several years.
If you waterproof plywood, make sure to cover all 6 sides thoroughly
You can also use a roof or foundation coating to cover your alternative plywood and waterproof it. This method will last longer and stand up to better traffic. However, a roof or foundation coating will not look very good.
Can you Use Regular Plywood to Build a Boat
It is not recommended to use regular plywood to build a boat. Unlike true marine plywood, which is naturally made to be extra waterproof, regular plywood will always be a weak spot.
You may consider using a regular plywood, properly waterproofed, as a temporary patch. However, if you are building a boat you want to last, you need to use the real marine plywood.
Where Can You Find Marine Plywood
Marine plywood can be found at most home improvement stores in their specialty plywood section. It comes in 4’ x 8’ sheets usually, though you may find it in larger sizes and you can almost definitely order it larger.
If you do enough home improvement projects, you will eventually have to use a different material than you normally would just to finish a project. There are several alternatives to marine plywood that are excellent candidates. Just make sure that you waterproof them correctly.