Varnish and stains are two great finishes, however, they have different features. So, what’s the difference between them?
The main difference is that varnish produces a protective film over a surface and protects it from moisture, scratches, and other damage. While, stain only improves (enhances) the color of wood, but doesn’t protect it.
Varnish is a clear top coat that protects and seals the surface underneath. It is made by blending resins, solvents, and drying oil. Once it dries, its solvent evaporates, and the remaining resins oxidize, forming a protective layer over a surface.
There are different types of varnishes, each with its distinct features and method of application. But, one factor that unites all types of varnishes is that they are used to seal and protect the material or finish underneath.
For instance, the exterior varnish is used for outdoor surfaces. This sealant is flexible and is designed with additives that make it UV-resistant. On the other hand, the acrylic varnish is water-based and has a colorful finish.
Other types include polyurethane, yacht, and alkyd varnish.
Related Read: Can You Apply Varnish Over Stain?
Wood stain) refers to a finish that alters the color of the wood. For example, you can use it to darker or alter the natural look of the wood grain. Stain is also known as a wood dye. There are different types of wood stains, such as gel stain, oil-based stain, water-based stain, etc.
This wood finish is made of colorant (paint pigments) suspended in a solvent. The solvent it uses depends on the type. For example, a water-based stain uses water as its solvent, while an oil-based stain uses oil as its solvent.
In comparison to other wood finishes, wood stain doesn’t protect the wood. Instead, it offers a colorful and vibrant finish.
Stain vs Varnish
So which of these two finishes is better? Let’s compare both to find out. Let’s start with the paint make-up.
The Paint Make-Up
The paint formula refers to the ingredients used in making the finishes. Varnish is made from resins, chemicals, and drying oil. These substances are dissolved in a solvent. Once the solvent evaporates, the remaining resins produce a protective layer.
Some types have more paint pigments than others. For example, acrylic varnish has paint pigments suspended in the coating to give its finish more color.
On the other hand, the stain is made of paint pigments and a solvent (water or oil). Though it also contain binders, the binder makes up less than 30% of the paint volume.
Varnishes are more difficult to apply than stains because they have a clear coat (finish), so imperfections on the surface show once the sealant dries.
So, before you apply it, you must do a lot of prep work. This includes cleaning, degreasing, and sanding. You also need to thin it before painting. All of this makes its application difficult.
The prep work depends on the type of varnish. For instance, to apply polyurethane varnish, you must use a spray gun. However, for acrylic varnish, you must use a natural bristled paintbrush.
On the other hand, wood stain is easier to apply. All you need to do is to sand the surface and then apply it. You can use a paint roller, paintbrush, or spray gun to apply it.
Varnish is more durable than stain because it forms a thick and protective layer over the surface. This layer protects the surface from water, moisture, scratches, and damage.
Some varnish types have additives that make the finish UV-resistant. All of these additives make the finish last longer on a surface. On average, varnish lasts up to 15 years if applied properly.
On the other hand, wood stain isn’t durable and will last less than 5 years on indoor surfaces and less than 1 year on outdoor surfaces (unsealed). That’s because it doesn’t have additives that make the finish resistant to water or weather elements. This finish is only used to change the color of the wood.
Indoor or Outdoor Use
You can use varnish indoors and outdoors. Since it is resistant to water and weather elements, you can use it outdoors. All types have additives that make the finish water and UV-resistant. However, for the best results, use exterior or spar varnish varnish outdoors.
On the other hand, wood stain is more suited for indoor use because it isn’t durable or resistant to water. As such, it can’t withstand the harsh exterior environment and will peel off. However, some types, such as deck stains, are designed for exterior use.
Cleaning and Maintenance
Varnish is easier to clean than stain because it forms a glossy finish that attracts less dirt and debris. Even if dirt accumulates over the its coating, you can wipe it off with a clean rag and warm water.
On the other hand, the stain is harder to clean and maintain. Since it isn’t moisture resistant, its finish has no protection against mold. Also, it attracts a lot of dust, so you must clean it more often. Repeated cleaning with water will wear off the stained surface and cause the color to fade.
Wood stain dries faster than varnish because it has fewer additives and uses water or oil as its solvent. So, its solvent evaporates faster. On average, stain takes 1 hour to dry enough for a re-coat. However, its coating must dry for 48 hours before sealing it.
On the other hand, varnish takes longer to dry. On average, its water-based type takes 6 hours to dry enough for a re-coat, while its oil-based type takes 24 hours.
The Paint Cost
Varnish costs more than wood stain because it offers more protection and is more durable. The price of varnish depends on the type. For instance, acrylic varnish costs less than polyurethane varnish.
On the other hand, wood stain doesn’t cost as much, and you can buy it in small quantities. For instance, you can get a half-pint, a pint, or a gallon.
Varnish has a thick, clear, and glossy finish that is moisture-resistant. Most types produce a transparent film with no color tint.
However, some types are designed with paint pigments, such as acrylic varnish. To get a colorful finish, you can also mix varnish with paint (such as acrylic paint).
On the other hand, stain offers a dry and smooth finish that isn’t glossy or thick. However, most wood stains are usually sealed with glossy topcoats (such as varnish) to get a glossy finish.
Wood stains penetrate the wood and prevent moisture from soaking into the wood pores and damaging it. However, its level of protection is low as it isn’t UV-resistant and won’t protect the wood from constant water or moisture.
On the other hand, varnishes will protect the wood from moisture, water, UV rays, rain, scratches, damage, and more. When dry, they form a thick protective layer that repels moisture and protects the surface.
Here is a chart that summarizes the difference between these two wood finishes:
|Durability||Good (up to 15 years)||Moderate if left unsealed|
|Exterior Use||Good||Poor, except exterior wood stain.|
|Cleaning and Maintenance||Easy||Moderate|
|Paint Drying||Up to 48 hours||Less than 12 hours|
|The Finish||Glossy and thick||Smooth and dry|
Which One Do You Need?
Before you decide on which to go for, consider the following factors:
- Budget – Varnish costs more than wood stain.
- Protection or Color – If you want to protect the surface, go for a varnish finish as it protects surfaces better. If you want to alter to wood color, go for a wood stain as it will make it appear lighter or darker.
- Outdoor or Indoor – For outdoor surfaces, go for varnish. For indoor wood surfaces, go for wood stain.
Tip: To get the best out of these two finishes, apply a few coats of stain, then seal it with varnish. The stain will produce color while the varnish protects the finish and the wood underneath.
Wood stain and varnish are both great finishes. However, they are used for different things. Wood stain is used to alter the wood grain color, while the varnish is used to protect the surface underneath.
Tony is a professional painter and an author of DIY Geeks. Tony has completed over 1,000 painting projects for his clients. It's safe to say he knows what he Is talking about,