When it comes to wooden finishes, there is hardly any other finish as strong or durable as Tung oil and polyurethane varnish. Both finishes offer impressive moisture resistance and wood protection. But what’s the difference between both finishes?
The difference between polyurethane and Tung oil is that Tung oil is a natural finish while polyurethane is a synthetic or man-made finish.
Tung oil is extracted from the Chinese Tung tree while polyurethane is made up of several resins, urethane compounds, chemicals, and solvents.
Polyurethane is also designed with more additives than Tung oil. Tung oil takes longer to dry than polyurethane. On average, Tung oil will dry fully in about 3 days while polyurethane can dry fully in about 24 hours.
There is more to know about the differences between Tung oil and polyurethane and this post digs right into the topic. So, let’s dive in.
What is Tung Oil?
Tung oil is a natural finish gotten from the extracts and seeds of the Chinese Tung tree. Tung oil is a very traditional and old finish commonly used on wooden surfaces including furniture. Like all wood oil finishes, Tung oil is a penetrating film that soaks into the wood. This means that Tung oil needs to penetrate the wood to stick properly.
Tung oil also has a long dry time. On average, Tung oil takes 3 days to fully dry but raw Tung oil can take weeks to dry. With Tung oil, you need multiple (5-7) coats to properly cover a surface. This prolongs the dry time of the finish as well. You should know that Tung oil dries hard but the top layer is usually prone to scratches and stains.
Also, you are required to touch up or reapply the oil finish at least every year. This is because the finish isn’t very durable and it wears off quickly. This means that Tung oil isn’t a good choice for busy and high-traffic areas.
What Is Tung Oil Used For?
- Tung oil is used to achieve a glossy finish
- Tung oil helps to reveal the wood grain
- Tung oil is commonly used on kitchen equipment because the finish is food safe
- Tung oil is used to cover and protect wood
- Tung oil is used on wood décor and sculptures to reveal the details and carvings in the wood.
What is Polyurethane?
Polyurethane is a synthetic or man-made varnish made by combining solvents, chemicals, resins, and urethane compounds. Polyurethane is a clear coat that is rarely used over bare wood. This is because, unlike other sealants and oils, polyurethane doesn’t penetrate the wood pores. Instead, polyurethane stays on the surface making it a great choice to use over other stains and paints.
The main ingredient in polyurethane is urethane compounds. Urethane is a plastic-like substance that is flexible, moisture-resistant, and durable. Asides from urethane compounds, polyurethane also has several additives in its formula that are designed to reinforce the finish. This makes polyurethane a very strong finish. Polyurethane also dries quickly as the finish dries fully in about 24 hours.
You should know that there are two main types of polyurethane; oil-based and water-based polyurethane. The oil-based type is more common because it is stronger and more durable. Also, you only need 2-3 coats of oil-based polyurethane. Water-based polyurethane on the other hand needs 4-5 coats but the finish doesn’t smell as much as oil-based polyurethane and is easier to apply.
What is Polyurethane Used For?
- Polyurethane is commonly used to seal stains and paints
- Polyurethane makes wood moisture resistance
- Polyurethane is used to protect wood
- Polyurethane varnish is common on high-traffic
- Polyurethane is used to protect antiques and old furniture from dents and pest damage.
So is polyurethane better than Tung oil? Let’s find out by comparing both finishes.
Polyurethane vs Tung Oil
To compare polyurethane and Tung oil, we would use the features of both finishes and see which finish stands out.
Here is a table that shows the major differences between Tung oil and polyurethane:
|Color||Tung oil has an amber-like tone||Polyurethane is a clear coat so it doesn’t have any color|
|Application||Tung oil is applied with a cloth||Polyurethane is applied with a paintbrush or spray gun|
|Price Tag||Expensive||Cheaper than Tung oil|
|Moisture Resistance||Average||Very good|
Next, let’s check out these differences in detail.
Tung oil adheres or sticks better to wood than polyurethane. This is because Tung oil penetrates the wood pores to stick while polyurethane sits on the surface. When you apply Tung oil, the wood oil soaks and binds to the wood grain.
Polyurethane on the other hand binds to the top layer of the wood meaning that polyurethane doesn’t stick as well as Tung oil. This is why it is very difficult to remove Tung oil from the wood. In most cases, removing Tung oil from wood will damage the wood because the wood oil has been absorbed by the wood.
Polyurethane protects wood better than Tung oil. This is because polyurethane is hard and moisture-resistant. So the wood will be protected from scratches, dents, and water.
Tung oil also protects wood but not as well as polyurethane. This is because Tung oil is not as hard or as moisture-resistant as polyurethane. Tung oil is prone to scratches, stains, and water rings so it’s not exactly the best choice to protect wood from damage.
Polyurethane is more durable than Tung oil. This means that polyurethane lasts longer than Tung oil. The reason for this is that polyurethane is harder and stronger than Tung oil.
On average, polyurethane will last about 10 years if properly applied and maintained. Oil-based polyurethane can even last longer than that.
Tung oil on the other hand doesn’t last up to a year, especially in high-traffic areas. The manufacturers of Tung oil will even advise you to reapply the Tung oil at least once a year because the finish wears off easily. So in terms of durability, this is a flawless win for team polyurethane.
What color does the finish give?
You should know that polyurethane is a clear coat meaning that the finish doesn’t give any color to wood. Instead, polyurethane forms a transparent layer that reveals the color and texture of the surface underneath. Though DIYers frequently claim to see yellow tints on their polyurethane finish, this is usually when too many coats of the polyurethane are applied.
Ordinarily, polyurethane has no color. If you want a color for your polyurethane finish, you will need to tint the polyurethane with flat paints or acrylic paints. You can also apply the polyurethane on a wood stain or paint to give the polyurethane color.
Tung oil on the other hand leaves an amber-like or gold color on wood. This color is very similar to the natural color of wood which is why most people don’t notice the amber-like tone that Tung oil gives.
Polyurethane can be applied using a spray gun or a bristled paintbrush. Polyurethane also comes in ready-to-use spray cans. This makes it comfortable to apply polyurethane as you can use any method you are comfortable with. Even if you have very little painting experience, you can handle the spray-on polyurethane as it’s easy to use.
Tung oil on the other hand is usually applied using a rag and some professional painters use foam to apply the wood oil. This is because Tung oil has to be wiped on the wood. You should know that Tung oil finish wears easily so you’ll have to touch up and reapply the finish at least every year.
There isn’t a specific cost for either finish but generally, Tung oil costs more than polyurethane. The reason for this is that the process of making Tung oil is expensive and time-consuming. For starters, the Tung tree where Tung oil is gotten from is only native to China. This makes it a bit difficult to get the needed resources to make the wood oil.
Also, Tung oil needs to go through processing to make it lighter since raw Tung oil takes forever to dry. Polyurethane on the other hand is easier to manufacture as the ingredients aren’t scarce. So polyurethane tends to be cheaper than Tung oil.
Polyurethane offers better moisture resistance than Tung oil. The presence of urethane (plastic-like) compounds in the polyurethane formula makes it impossible for moisture (water or oil) to penetrate the polyurethane coating.
Tung oil also offers moisture resistance but after a while, you’ll start to notice water rings and irregular lines forming on the Tung oil coating due to exposure to moisture.
The chemical composition of polyurethane also means that the particles are tightly bonded making it even more difficult for water to get through.
Cleaning and Maintenance
Both finishes are easy to clean and maintain but cleaning polyurethane is easier than cleaning Tung oil. This is because polyurethane doesn’t absorb stains or filth. So, you have less cleaning to do with polyurethane. Also, polyurethane is moisture resistant so whatever stain or filth that is on the polyurethane coating can be easily wiped off with a damp rag.
Tung oil on the other hand has a softer texture meaning that stains and filth can stick to the Tung oil coating. So you’ll have to clean the Tung oil more frequently than you would with polyurethane.
Asides from that, Tung oil is not as moisture-resistant as polyurethane so if you wipe Tung oil with a solvent or cleaner, the Tung oil may wipe off as well.
Should You Use Tung Oil or Polyurethane?
It’s difficult to choose between polyurethane and Tung oil but here are a few factors to consider to make your decision easier:
The Price Tag
Since polyurethane is cheaper, it is more pocket-friendly especially if you want to buy in bulk. Tung oil will cost you more than polyurethane so you should only go for it if you can afford it.
Polyurethane offers superior moisture resistance to Tung oil. So if you want to finish a surface that will be washed or cleaned regularly, it’s better to go for polyurethane. Also, if the surface to be painted will experience rainfall or leaks, polyurethane will be a perfect choice.
You need to reapply Tung oil at least once every year while you only need to apply polyurethane once. So if you know you can’t handle the task of touching up and reapplying the Tung oil, you should go for polyurethane.
Polyurethane offers superior wood protection so it’s better to choose polyurethane, especially on high-traffic areas or surfaces that will be used frequently. Tung oil also offers good wood protection but in high-traffic areas, the Tung oil will not protect the wood properly.
In summary, polyurethane and Tung oil are both great choices. Both offer good finishes and wood protection so the one you need depends on your choice, taste, and the surface you want to finish.
You should remember that Tung oil is more suited to indoor use and decorative wood while polyurethane can be used outdoors and in high-traffic areas.
Also, polyurethane is easy to apply and you only need to do so once. With Tung oil, you’ll have to reapply the finish as long as it’s on the surface. To know which of the two finishes you need, ensure to check the guide above.