Wood Oil vs Varnish (Which One is Better?)

Two of the most common finishes on hardwood are wood oil and varnish. Both finishes offer glossy protection but what’s the difference between both finishes? Here is the answer to that.

The main difference between wood oil and varnish is that wood oil needs to penetrate the wood to stick, while varnish binds to the top layer of wood. That means varnish is glossier, dries harder, and therefore protects the wood better than wood oil. 

Wood oil penetrates wood deeply while varnish stays on the top of the wood. Varnish lasts longer on wood, usually up to 10 years if properly maintained. Wood oil would have to be re-coated every 2 years or less.

So, do you need wood oil or varnish? Let’s find out in this article.

What is Wood Oil?

What is Wood Oil?

Wood oil refers to different types of penetrating oil finishes. Wood oils include Linseed oil, Tung oil, Teak oil, Danish oil, Mineral oil, and Walnut oil.

Many of these oils are plant-based meaning that they are gotten from part of different plants. For instance, linseed oil is gotten from seeds of the Flax plant while Tung oil is gotten from the Chinese Tung tree. So wood oil is generally a natural wood finish.

Being a natural oil, wood oil is known to penetrate deeply into the wood and this allows the wood oil to protect the wood from within. Since wood oil penetrates, it can’t crack or peel off like other finishes. But wood oil fades quickly and would need a recoat every two years or less.

What is Wood Oil Used For?

  1. Wood oil is used to enhance wood stain and paint
  2. The oil finish is used to reveal the texture and grain of the wood
  3. Wood oil offers moisture and wood protection
  4. Dry wood oil finishes are often used as undercoats for polyurethane
  5. Natural oil finishes help to give antique look to wood

Now that we know what wood oil is, let’s check out what varnish is.

What is Varnish?

What is Varnish?

Varnish is a strong and durable sealant or top coat used to protect wood and wood stains. You should know that the term “Varnish” is a family name as there are different types of wood varnish.

The list includes spirit varnish, polyurethane varnish, exterior varnish, acrylic varnish, and so on. Though there are different types of varnishes, they all have very similar features.

One binding feature of all varnishes is that they are topical finishes. This means that varnishes don’t penetrate wood as deeply as wood oils.

Varnish binds to the top layer of the wood. Since varnish doesn’t penetrate, the top coat is harder and stronger making varnish capable of protecting the wood. Varnish has a very glossy finish that repels moisture. Exterior varnish especially is very moisture-resistant.

What Is Varnish Used For?

  1. Varnish is used to protect wood from dents and pest damage
  2. Varnish is used to protect wood stain and paints
  3. Varnish is used to protect wood from water
  4. To offer a glossy finish
  5. Varnish can be used to deepen or brighten wood stain color.

Let’s now find out which wood finish is superior.

Related Read: Can You Varnish over Wood Oils?

Wood Oil vs Varnish

To compare both wood finishes, we’ll use the features of a proper wood finish and see how both finishes compare.

Here is a table that shows the major differences between wood oil and varnish:

 Wood OilVarnish
Wood ProtectionGoodGreat
Gloss or SheenGoodVarnish offers a higher sheen
Dry TimeTakes at least 3 days to fully dryDries fully in less than 3 days
PurposeCommon on bare woodCommon on stained wood
Water ResistanceGoodBetter
DurabilityPoor (recoat every two years)Great (lasts about 10 years)

Now, let’s go into detail to learn more about these differences.

Wood Protection

Varnish protects wood better than wood oil. The reason for this is that varnish doesn’t penetrate wood the same way wood oil does. Since the varnish doesn’t penetrate as much, there is more varnish on the top layer of the wood. More varnish on the wood equals more protection against moisture, dents, scratches, and blemishes.

Since wood oil penetrates wood deeply, there is less wood oil on the top of the wood and more wood oil inside the wood. The low presence of wood oil on the top of the wood means that it will not protect the wood as well as varnish.

Moisture Resistance

Both wood oil and varnish offer impressive moisture-resistance qualities. However, varnish remains water-resistant for years while wood oil begins to allow moisture to seep in after a year.

The reason for this is that there isn’t much wood oil on the top of the wood. So after a while and due to friction, the wood oil will wear off leaving the wood exposed to moisture.

Verdict: Varnish offers better moisture resistance long term.

Dry Time

Varnish dries quicker than wood oil. This is because there are drier additives in the varnish that make the varnish coat evaporate and dry quicker.

Asides from the driers in the finish, varnish is often thinner or lighter than wood oil. The thicker the finish, the longer it will take to dry. Since wood oil is thicker than varnish, it will dry slower.

Purpose and Use

Varnish is often used to cover stains and finishes on wood. This is because varnish doesn’t penetrate deeply so it wouldn’t be repelled by the stain underneath. Also, varnish is a clear film meaning that it will enhance the color of the wood stain.

Wood oil is used on bare wood rather than stains. This is because wood oil needs to penetrate to stick properly. If you put wood oil over wood stain, the stain will prevent the wood oil from penetrating deeply as it’s supposed to. So wood oil is better on bare wood or unfinished wood.

Verdict: Varnish can be used over stain but wood oil should be used on only bare or unfinished wood.

Durability

Varnish lasts longer than wood oil. One reason for this is that varnish contains driers and additives that reinforce the finish. Wood oil on the other hand has natural makeup with no solvent or additives.

Asides from this, varnish doesn’t penetrate as deeply as wood oil meaning that there is more varnish on the top of the wood to last for years. Wood oil will need to be reapplied every 2 years or less. This is because wood oil fades quickly. So you’ll need to touch up the wood oil.

The Price Tag

Varnish is cheaper than wood oil. Wood oil is costlier since it’s natural and it takes longer to extract. Also, varnish can be gotten easily from a blend of other compounds so it’s not scarce.

The scarcity of the source of wood oil also makes it more expensive. For instance, the Tung tree where Tung oil is gotten from is native to southern china so you can expect Tung oil to be costlier than your average varnish.

Indoor or Outdoor Use?

Varnish can be used indoors and outdoors but the finish is more suited to exterior wood. Since varnish offers better wood protection, it will last longer on outdoor wood.

Also, varnishes like polyurethane and exterior varnish offer resistance against rainfall, heat, and UV rays. Wood oil can’t compete with varnish for exterior protection since wood oil has low weather resistance.

However, wood oil can be used on virtually every type of indoor surface. Wood oil given its natural formula is usually considered healthy and food safe for baby furniture and kitchen equipment.

Verdict: Wood oil is suited to indoor use while varnish should be used on outdoor wood.

Cleaning and Maintenance

Varnish is easier to clean than wood oil. This is because varnish has a synthetic formula and as such can be cleaned with solvents easily. Also, the glossy sheen on the varnish means it doesn’t absorb dirt or dust nibs. So you’ll be doing less cleaning and maintenance.

Wood oil however will prove more difficult to maintain. The natural formula of wood oil means that solvents may discolor the finish.

Sheen Level

Wood oil has less sheen than varnish. Vanish due to the compounds in the finish has more sheen and is glossier than wood oil.

Do You Need Wood Oil or Varnish?

If you are still confused about if to buy varnish or wood oil, here is a guide showing important factors to consider. Hopefully, something here will make your decision easier.

The Price Tag

You should only purchase a finish that you can afford. Pure wood oil is often costlier than varnish due to the natural matter in the finish. A pocket-friendly option here will be varnish.

Wood Protection

Since varnish protects wood better, it will be ideal for floors and busy surfaces. Wood oil can be used to protect wood that wouldn’t be used heavily. Examples of such wood include photo frames, kitchen equipment, and the likes.

Indoor or Outdoor Use?

If you want a finish for indoor use, wood oil is better. Since wood oil is natural and pure, it is safer for indoor surfaces. The high level of additives in varnish means it’s not always the best option indoors but varnish will perform well outdoors.

Final Words

Overall, varnish and wood oil are both great finishes. The one you go for depends on your needs and type of surface.

Wood oil penetrates deeply so it should be used on bare wood while varnish can stay on an existing finish since it doesn’t penetrate as deeply as wood oil. Also, varnish offers better wood protection than wood oil. Wood oils are more suited to decorative tasks.

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