Does Polyurethane Make Wood Waterproof?

Adding Polyurethane on your wood surface could be a great step in having better protection for your wood. You need to know whether this will make wood waterproof. Generally, Polyurethane does not make wood waterproof.

Polyurethane seems to make wood waterproof for a few days, after which the wood lacks the waterproof characteristic. This is due to the breaking of the layers of coats formed whenever you apply Polyurethane on the wood surface after time.

This is due to the contraction and expansion of wood following the moisture it contains even if the kiln is dried. Nevertheless, Polyurethane plays a great role whenever you apply it on wood in giving it durability for a long-lasting service.

Therefore, you may not automatically disregard its importance on wood. With this, let’s have a close look at whether Polyurethane will make wood waterproof and what we expect it to do to our wood furniture.

Does Polyurethane Protect Wood from Water?

The answer is No; Polyurethane will not protect the wood from water. Nevertheless, it is essential to increase the durability of the wood by forming a plastic-like coating that is highly durable.

Here is what you need to know about how Polyurethane works, making it not protect the wood from water.

To have the best protection service from Polyurethane, you will have to add several layers of coats on the wood rather than having a single layer of coat. Unlike most finishes, Polyurethane does not penetrate inside the surface of the wood.

However, it usually provides an abrasion-resistant seal for your wood. Upon drying on the wood surface, Polyurethane forms a hard protective coat that is transparent.

It will protect your wood from wearing out hence increasing its durability rather than protecting the wood from water.

Despite any effort of putting up extra coats on the wood, there will be holes left on the surface of the wood. First, the thing you need to know about Polyurethane is that it is plastic.

As a result of this, whenever you apply Polyurethane to the wood, it will form a coat of its own on the wood.

On adding a coat to the wood of the Polyurethane, you for a thin coat. However, the coat is not continuous and it will contain some holes in it.

The layer of the plastic formed will be on the wood surface, but the holes from the discontinuous coating make this Polyurethane not to make the wood waterproof.

Nevertheless, you may prefer adding extra coats on the wood surface. This is likely to create a thick coat with a continuous layer of the Polyurethane.

Normally, when the polyurethane layer is continuous, it will make wood waterproof.

However, due to the contraction and expansion of wood naturally, the layer is broken as it is tough, forming a plastic layer. This will then create the discontinuous layer of the Polyurethane added on the wood surface.

As a result of this, the wood surface will just become waterproof for a short period of time, after which it will then take in water.

How do You Make Wood Waterproof?

Making wood waterproof is essential in contributing to the durability of the wood. The use of wood in bathrooms and other areas exposed to water and moisture increases the need for making wood waterproof.

Polyurethane will not give you the best solution in making wood waterproof. However, there are some mixtures of Polyurethane which are said to be waterproof.

Despite some of the polyurethane mixtures being waterproof, you will have to use them with other chemicals to ensure that the coating does not leave holes, whether there be contraction and expanding or not.

The use of fiberglass cloth and epoxy resins has been an amazing solution in waterproofing for wood. Epoxy resin has proved to provide tough and a waterproof finish to a wood surface. However, this will need you to take a longer period of time to allow the full curing of the epoxy resin.

This is so as epoxy will need at least 24 hours to ensure that it fully cures. After curing, the epoxy resin will provide an amazing finish, which also provides enough sealing above the stain.

Below are some of the ways in which you may use to make wood waterproof;

Ways to Make Wood Waterproof

Use of Wood Oil to Make Wood Waterproof

There are different types of wood oils you may use in making wood waterproof. Some of these wood oil include Linseed Oil, Walnut Oil, and Tung Oil.

Tung Oil is essential for small wood projects considering that it is expensive. Walnut Oil is similar to olive oil though it is not used for commercial purposes due to nut allergies.

Linseed oil is the most used wood oil for making wood waterproof. While using linseed oil, you can opt to purchase the raw linseed oil for DIY while you can use the boiled linseed oil for outdoor furniture.

After you have the linseed oil, create a mixture to make a sealant through mixing the oil with the use of apple cider vinegar and turpentine to create a durable finish.

Sand and clean the wood surface that you are to apply the linseed oil mixture.

After all is done, apply the mixture to the wood surface forming the first coat. Wait for the first layer to cure until it absorbs.

After the coat is dry, rub any excess oil and then leave your wood to cure for about 24 hours. You can add more coats as you may love through repeating the same procedure.

Use of Sealants to Make Wood Waterproof

This is an amazing way of making wood waterproof. It will require you to purchase a water-based wood sealer from any home improvement store.

The sealants you find will be labeled depending on the material you need to use them on. These sealants will include outdoor sealant, deck sealant, floor sealant, fence sealant as well as furniture sealant.

Clean the wood surface that is to be waterproofed through sanding then cleaning away the dust off the surface. Depending on the type of sealant, you may use either paintbrush or spray the sealant to create a coat on the wood surface.

One of the key things you need to note while using sealants to make wood waterproof is that they evaporate easily; hence you need to ensure that you are working under friendly temperatures to ensure that the sealant dries easily.

Ensure you let the surface dry depending on instructions in the different sealants. After the coat has cured, you can then apply another coat to the previous coat.

However, to ensure there is an improved adhesion on the second coat, sandpaper the first coat finely.

After all the coats you need are ready, ensure to give the wood several days for full cure before using it.

Use of Stain to Make Wood Waterproof

To use a stain to make wood waterproof, you may prefer using the oil-based semi-transparent stain. Normally, the lighter your stain is, the more it has oil content in it. However, not every light stain will be suitable for your wood.

Light stains are perfect for any interior projects on woods, which will be less exposed outdoors. With the right stain, prepare your wood from which you will be able to note any imperfection on the wood surface as you apply the stain.

Through the use of sandpaper, sand the imperfections visible until the surface looks even. After confirming that the wood surface is even, apply the initial coat through the use of a paintbrush from one even direction.

After this, cover the stained surface and let it dry for at least 4 hours to a day before you apply the next coat. After it has cured, remove the excess stains and then reapply another coat of the stain finish.

What Does Polyurethane Do for Wood?

Polyurethane makes wood to gain an abrasion resistance over wear. This makes it be highly durable and provide you with a long-lasting service. Polyurethane forms a tough layer on the wood surface without being absorbed by the wood.

This layer formed is usually plastic-like hence making the surface of the wood to be tough, causing it to resist any damage and wear. However, Polyurethane does not provide enough waterproofing characteristics to the wood.

This is so as it does not penetrate the wood. At first, it will make wood waterproof; however, after some time, some holes without the Polyurethane emerge, considering that wood will contract and expand after a period of time due to moisture contained in the wood. This will be so despite the kiln water being removed.

Final Words

In conclusion, Polyurethane has created many arguments for homeowners. The main subject for these arguments being whether Polyurethane makes wood waterproof.

It could be quite confusing as, in reality, Polyurethane does not make wood waterproof. At first, it will make the wood waterproof, but after some time, the wood will not be waterproof again. If you need to use Polyurethane to make wood waterproof, then you will have to keep filling up the holes developed on the surface.

Nevertheless, Polyurethane is an amazing sealer that will provide extra durability to your wood furniture hence making it an amazing choice for your furniture.

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