How to Treat Wood for a Shower?

Shower walls, ceiling, subfloor, window frames, sink, washbasin, or even bathtub in the bathroom can now be built with wood, and for good reasons.

However, before you decide to use wood for your bathroom, you must prepare and protect it from water (or excess moisture) by getting it sealed and waterproofed. Wondering how to do that?

Well, in this article, I will share with you a few solid tips that will help waterproof the timber you use in the bathroom – where water is a culprit but can’t be avoided.

Waterproofing Wood for Shower

Waterproofing wood in the shower room is crucial to preserve wood’s strength, integrity, and natural beauty.

Adequately sealing the timber prevents water absorption, which can otherwise cause rot and decay.

So, without any further ado, let’s get started with wood waterproofing methods that are simple to follow and apply:

1. Choose the Right Wood Species

When it comes to waterproofing bathroom subfloors and other surfaces, remember that certain wood species are more resistant to water and moisture than others.

Some of the best options are western red cedar, chestnut, larch, Douglas fir, teak, and white oak.

Choosing these specific water-resistant wood species for showers and bathroom means you will have an easier time waterproofing and protecting the surfaces.

If you use plywood instead of solid wood (due to lower prices or other reasons), make sure you go with marine-grade plywood, which is specially treated to resist water damage.

2. Use a Water-Resistant Oil Coating

Another good way to waterproof wood for your bathroom and shower areas is by using wood oils like linseed oil, walnut oil, and tung oil.

For all these oils, following these procedures will help keep water away from your wooden bathroom decor and furniture.

Step 1- You’ll want to start by sanding down the wood surface to smooth out any rough edges.

This step is important because otherwise, the rough surfaces will become visible once you’re done oiling, and they won’t look very attractive.

Step 2- Prepare your preferred oil by blending and making it stronger.

To make a stronger waterproofing oil, mix the oil with either turpentine or vinegar. Stir until the ingredients are thoroughly combined.

Some oils in the market are already blended and mixed with other chemical additives. So, this step isn’t essential if you’re planning to use a thicker blended oil without diluting.

Step 3- Using a soft-bristle brush, cover the wood surface area evenly until oil is absorbed, making sure to get into all the nooks and crannies.

During the process, do not forget to clean off the excess oil residues with a clean rag.

Step 4- Allow the surface and edges of the wood to absorb the oil for a little while so you can identify which areas haven’t been touched. Then, you can apply more oil to those areas as needed.

Step 5- Let the wood sit for a couple of days after applying the product and before using it. This way, the wood will have time to settle and absorb what it receives.

3. Apply a Water-Repellent Sealant

This method uses a waterproofing wood sealer such as spar-urethane that can be sprayed or brushed onto the cleaned, sanded wood surface.

• For ideal results, apply sealants at room temperature. Otherwise, the potency of the sealant may be affected by heat.
• Do not stir or shake the spar-urethane sealant like other liquids – this will cause it to dry too quickly.
• Apply at least three coats, giving each coat time to dry before applying the next.
• Allow air circulation during and after application for best results.
• After the topcoat, give the wood enough time to get absorbed and offer the needed protection before using it (3 days should suffice).

Ensure you reapply the sealant every year or two to protect the wood surfaces in your shower room adequately.

4. Waterproof Wood with Stain/Paint and Sealer

This is my favorite method as it does the best long-lasting job of waterproofing the wood indoors or outdoors.

Especially for bathrooms where the beauty of wood does matter, this method will make the wood look more elegant and attractive by adding the colors you love to see.

You can choose waterproofing paint, stain, or a powerful stain-sealant combo for this method.

Combination stain-sealants, I think, are best because of their translucent shade that won’t obscure your view.

Just keep in mind that lighter stains generally contain more oil. So, don’t be alarmed if the wood looks shiny after its application.

The application process is the same as any other stain or sealant…

• Simply wipe the wood dry
• Sand it down to create a smooth surface
• Apply your preferred paint or stain with a brush
• Remove residues with a clean rag, and allow the surface to dry
• Reapply up to two or three times afterward for best results, if needed.

Remember that most stain sealants are quickly absorbed into the wood and don’t require wiping.

The only exception is the alkyl-based stains that leave some residues on the wood surface but will offer a more aesthetic appeal and charming beauty to interior woods.

Moreover, if you are using paint for waterproofing the unfinished wood (rather than the finished wood surface), remember to use a primer before that helps adhere the paint better.

Choosing the Best Waterproof Wood Paint

Before picking any product, check if you want one that will work on multiple surfaces like wood, metal, concrete, etc. If that’s the case, it’s good to pick the most versatile one.

However, if you know you’ll only be painting wood, get a specific wood paint.

The durability of a product is also essential to know before you make your final purchase. It helps determine how well the finish will protect your bathroom surfaces without wearing off too quickly.

Some of the best waterproofing paints for wood that I think are most durable and effective are the following:

1. TotalBoat-409322
2. Wolman 360349
3. FolkArt Outdoor Paint
4. Diamond Brite Paint
5. Zinsser & Co Watertite Paint
6. Rust-Oleum Marine Topside Paint
7. KILZ 10211 Exterior Siding Fence and Barn Paint

If you plan to use the product on the interior and exterior wood surfaces, ensure that it’s resistant to scratching, scuffing, mold, mildew, and fading due to water damage and the sun’s UV radiation.

The Bottom Line

There’s no need to shy away from using wood in your bathroom just because water is present; with suitable waterproofing methods, you can still have rustic elements throughout the room.

The process you choose should be based on your budget for the project.

If it’s a large-scale project involving your whole house, opt for stain-sealant as it is more efficient and time effective. But for a smaller project like waterproofing your shower, any three methods I discussed above will do; it all comes down to preference.