For best results, follow the mentioned timeline. Primary purpose of stains is to saturate wood with pigment in order to change its color. VOC refers to ‘Volatile Organic Compounds’. The essential element for a proper and smooth finish is even coating. It is perfect to use it for underwater applications like boats. Usually you use a simple brush to stroke it onto your plywood surface. Plus, it is a reasonably moisture resistant manufactured wood to boot. It is mandatory to procure user consent prior to running these cookies on your website. Thompson’s water seal is known for its high levels of waterproofing, and the ability to clean and treat in one single day because you can apply it … Our step by step guide on how to seal plywood for outdoor use will assist you even with sealing rough surfaces. This causes the plywood to appear waxy. Shop waterproofers & sealers and a variety of paint products online at It is better to sand in back and forth motion and along the natural grain of the wood rather than across the natural grain. No Nonsense Water Repellent Seal Clear 5Ltr (57474) Clear, high performance waterproof treatment for exterior porous surfaces. Aquarium sealant is a silicon sealer that is regularly used on marine ships, aquariums, vivariums, and outdoor plumbing. The way you calculated seems fine from my point of view. We'll assume you're ok with this, but you can opt-out if you wish. This category only includes cookies that ensures basic functionalities and security features of the website. I am using plywood for an exterior skateboard ramp. Check out the latest prices for Thompson’s WaterSeal over on Amazon. If you wish to seal both sides of the plywood, do it in steps. Thanks, James, According to my point of view, you can apply polyurethane stain or paint (high gloss). How Long Will Untreated Plywood Last Outside? Well, all of those ply layers are glued together using a water resistant adhesive that is great at repelling moisture. Is it best to use Polyurethane Varnish on the edges and perhaps the underside of the edges? This wood lasts longer even in unfortunate drainage systems. I want to put decals on the side and then then varnish the entire kicker ramp, leaving it in a natural looking finish. This is an oil that as the name implies penetrates the surface … Yes, because plain plywood board is not rot-resistant. These cookies do not store any personal information. So lets take a further look at what you need to know before you start work on waterproofing your plywood project…. Follow Guidelines It can be really crucial to follow the guidelines of your product’s manufacturer when you are learning how to waterproof plywood. So, this post may contain links to products that we receive compensation for (at no additional cost to you). Otherwise those VOC fumes could hurt your bearded dragon, turtle, or pet snake. Always select suitable plywood for your exterior project and then seal it step by step. water sealer on subfloor? This site contains affiliate links to products. And it would completely keel over by the end of year two! While it may be water resistant, it is not water tight. Sealing plywood has any advantages. The answer to this is very simple… you coat it with a waterproof substance that ‘seals’ the plywood in. To prevent it from happening, seal your wood as soon as possible. This is the same glue you would find in both school glue (for sticking paper together) to carpenter glue (like ‘Elmer’s Glue). It protects plywood from water … However, the sealing project can be sometimes tricky when it comes to sealing rough surfaces. Would sealing the exposed side with 1:1:1 (thinner, spar varnish, and linseed oil) cause the plywood to delaminate? We prefer clear, penetrating epoxy because it works its way deep into the wood, dries … It normally comes in piles of 3, 5, 7, 9, and the lowest number indicates the uppermost class of a CDX plywood. Now, just using latex sealer is typically not enough to seal up plywood end grain. You should always take the time to seal plywood before you add a coat of paint. This sealer is great for guarding plywood against water penetration. We are sure that you have got complete knowledge of sealing plywood and will be able to seal your wood like a pro! Cover the surface with masking tape. This gives plywood a long-lasting finish. The sealer protects by wrapping plywood in a plastic water-resistant covering. If you are sealing a wood that usually looks great with an orangy/amber tint, choose an oil-based sealer…water … Sealing keeps plywood strong and prevents it from shrinking, expansion and twisting. Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. Simply put, yes, you can use this brand of sealer on plywood. I used 1/2” ply on the walls of my wood shop. They usually come under manufacturer's names. I suggest to use Polyurethane Varnish on the edges. Avoid it using on the surface of the plywood. Speak to the professionals at Curtis Lumber & Plywood in Springfield, Virginia to learn more about the process to seal Marine-Grade Plywood… We plan on painting it in about 6 months as well. Save my name, email, and website in this browser for the next time I comment. If you are working on any siding project, choose a T1-11. You also need a clean paintbrush to apply the sealer. By sealing this material, however, you can increase its overall lifespan. Don't worry! Sunlight rays also damage the wood. Yes, Polyurethane varnish will be a good option for top, sides and bottom. If you had a piece of untreated and unsealed plywood, and you used it on an outdoor structure, it would last about 2 years. PVA (Polyvinyl Acetate) is a water-based emulsion adhesive that is regularly used to glue everything from boxes to books. If you are sealing a wood that usually looks great with an orangy/amber tint, choose an oil-based sealer…water-based … For plywood that is finished, you will usually only be able to use spray-on sealer since you want to make sure you keep the existing look of the wood. It is also a better sealer because it absorbs about 3% of water. This is because all those ‘voids’ along the sheets side can prove to be a problem. Those chemicals then infuse deep into the grain, making the wood resistant to rot and burrowing insects. The proble is with water intrusion through delamination and unsealed holes. This is especially the case when you consider how easy those exposed ply edges make it for water to seep in. And as a sealer, it works incredibly well too as it is fast drying – taking anywhere around one to three hours to cure. Water-sealed wood has been sealed with a chemical substance that prevents water from soaking in.