Is Tung Oil a Waterproof Finish?

paint outdoor table top with waterproofing tung oil finish.

If it is your first time finishing with tung oil, you might ask whether it can waterproof wood. Well, tung oil is a good sealant; it can seal the wood and make it waterproof. Tung oil, of course, is a natural product taken from tung tree nuts. The natural oil produced from these nuts can protect and enhance the wood’s natural beauty.

The tung oil finish functions like a water-repellent coat on the wood surface. It is very safe to use on wood surfaces, providing the wood with a coating that protects it from water droplets, moisture, and dust. Once it dries, it hardens and works like a coat of plastic on the wood surface. 

How Does Tung Oil Work?

When you apply tung oil on the wood surface, it will readily harden upon immediate exposure to air via polymerization. It absorbs around twelve percent oxygen from the ambient atmosphere, creating a waterproof top layer on the wood. 

Its chemical components continue polymerizing as it reacts continuously with oxygenated air, producing a thin and water-resistant film on the wood surface. This process means when you apply tung oil, you can prevent water and moisture from imbuing the wood fibers, making them invulnerable to the side effects of moisture. 

Thus, it is a popular choice of finishing for wooden furniture. Besides, it is natural and provides a bright color. The tung oil coat makes the wood impervious to the effects of water. Thus, your wood becomes safe from raindrops and spillage. 

Yet, for the tung oil finish to work well, you must allow it to cure completely. You can apply several coats of tung oil and never miss an area or spot on the wood surface. Of course, tung oil is still incomparable to varnishes. Nevertheless, it is a practical finish for sealing the wood.

How Long Can Tung Oil Waterproof the Wood Surface?

Tung oil comes in different brands and compositions. First, Tung oil comes in several types. First, there is pure tung oil which is unadulterated and free of additives. The waterproofing effect of this type of tung oil can last up to six months. Thus, if you want to prolong the waterproofing effect of pure tung oil, you must make additional applications to the wood surface. 

Another type of tung oil is Formby’s, also called Brand Minwax Tung Oil. It is not pure but contains varnish for enhanced drying properties. You will also find polymerized tung oil and Dark tung oil. 

Pure tung oil takes three days to dry, while oil wipes take only half an hour to dry. One caveat when applying tung oil on wood is to make it cure for a month to one and a half months. This way, you can ensure that it has settled in and dried completely before using the wood or subjecting it to use.

How many Tung Oil Coats Should You Apply to Ensure Optimum Waterproofing of Wood?

You must consider several factors when applying tung oil. Besides, the number of coating would depend on these factors. These factors include wood type, desired sheen or glossiness, and level of waterproofing you would like to achieve. 

Experts recommend applying around six to eight tung oil coats to ensure optimal waterproofing effect. Of course, it would necessitate enough patience to apply up to eight coats of tung oil, but woodworking is often all about patience. Remember, it takes time for a coat to dry. 

Thus, you must exert time and effort to ensure that each coat dries entirely. Then, you must wait several weeks to ensure that the coatings have already been cured properly. 

Another thing is the number of tung oil coats depends on what type of tung oil you are applying. If you are using pure tung oil, it will take up to three days to dry completely. Besides, you need to apply tung oil over time constantly. Moreover, it will be best to monitor the wood surface weekly to ensure that the tung oil finish is not damaged or compromised. 

Applying pure tung oil, of course, will require more patience. You can’t rush the application of coatings. Otherwise, the finish will be insufficiently capable of waterproofing the wood surface. Besides, if you rush the curing process, wrinkles may appear on the wood surface. Thus, you must sand the surface to do away with wrinkles. 

However, using varnishing wipes or oil blends can be less taxing because they contain additives that allow them to dry fast. Besides, they are easier to apply than pure tung oil. 


The answer to the question of whether tung oil can provide a waterproof finish to wood is always an affirmative one. The reason is that tung oil provides the wood surface with a plastic-like finish, impervious to water and moisture. As such, it is an excellent choice for providing your wood projects with excellent protection from water and humidity. 

Yet, there are many other options if you want to provide your wood projects with optimum protection against water and moisture. Aside from tung oil, you can use oil-based varnish, polyurethane, and lacquer.  

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