If you want a clear finish, you can use varnish or lacquer. Both sealants are good but have different qualities. So, what’s the difference between these two sealants?
Varnish is a synthetic finish gotten by mixing resins, dries, and thinning compounds. In comparison, shellac is a natural finish gotten by the secretion of lac bugs.
The synthetic formula makes varnish dry faster and harder. But, the natural formula of shellac offers better moisture resistance as its particles are naturally bonded and compact.
Varnish
Varnish a synthetic wood finish gotten by combining solvent, oil dries, and resinous compounds. These compounds are mixed with paint thinner to create a durable and strong finish.
There are different types of varnish; acrylic, exterior, spar varnish, and so on. Each type has a unique set of features, but all types of varnish protect surfaces from moisture, water, and scratches.
When dry, varnish forms a thick, transparent, glossy layer over the wood. Due to its compact structure, this layer becomes water-resistant and hard enough to withstand dents and scratches.
Varnish doesn’t need to penetrate the surface to stick; it can stay over the top layer and dry there. So, you can use it over wood stains to increase the durability of the stain. However, you must lightly sand the surface before applying it.
You can use varnish:
- To protect wood surfaces from dents, moisture, and scratches.
- To protect wood stains or paints.
- Exterior varnish protects outdoor wood from weather elements.
- To reveal the wood grain.
Shellac
Shellac is a natural clear coat used to finish wood. This natural wood finish is gotten from the secretion of an insect. The lac bug secretes a natural resin called lac. This resin is collected and processed to create a shellac wood finish.
Because of its natural formula, shellac offers impressive moisture resistance because its particles are compact and naturally bonded. The moisture resistance of shellac is so good that you can use it as a stain-blocking primer.
You must wait until shellac dries fully (cures) for it to become moisture-resistant. After the wood finish dries, you shouldn’t wipe it with a solvent or alcohol as you can remove it. It takes shellac 3 days to fully cure and become resistant to moisture, water, or scratches.
You can use shellac:
- To make wood moisture-resistant.
- Over non-wood surfaces.
- Since it’s a light finish, you can use shellac to reveal the wood grain.
- As a stain-blocking primer.
Shellac vs Varnish
To compare these two wood finishes, we will use the features of each finish and see which one is better. First, here’s a list that identifies the differences:
| Shellac | Varnish | |
|---|---|---|
| Wood Protection | Good | Better |
| Moisture Resistance | Great | Good |
| Thickness | Shellac is thin | Varnish is thicker than shellac |
| Formula/Make up | Natural | Synthetic |
| Durability | Good (up to 5 years) | Great (Up to 10 years) |
| Coats Required | 4-5 coats on wood | 2 coats are usually enough on wood |
| Paint Application | Easy (beginner level) | Average (requires some experience) |
| Indoor or outdoor use? | Shellac is suited to indoor furniture | Varnish will thrive on outdoor wood. |
Now, let’s check out these differences in detail.
The Formula
The varnish formula contains synthetic resins, solvents, oils, dries, and additives. These compound give varnish a hard and durable finish that protect surfaces from different elements.
On the other hand, shellac has a natural formula gotten from insect secretion that doesn’t contain solvents or additives.
Wood Protection
Varnish protects wood better than shellac because it has additives and resins that reinforce the finish. These additives make varnish harder and more protective than shellac which contains only a few additives.
Moisture Resistance
Compared to other wood finishes, shellac offers superior moisture resistance to surfaces. This is because shellac has a natural formula, meaning the paint particles are naturally bonded and compact. However, shellac must fully dry to become moisture-resistant, which can take a few hours.
On the other hand, varnish cures as it dries, so it becomes water-resistant faster. But, the moisture-resistant qualities of varnish aren’t as good as the shellac qualities.
Durability
Varnish lasts longer than shellac because it is formulated with extra additives that make the finish more durable and harder. At best, shellac will last for 6 years, while varnish can last up to 10 years if applied and maintained properly. Both finishes will last longer indoors than outdoors.
Purpose and Usage
Varnish is used to cover bare wood or wood stains and paints on the wood. On the other hand, you can use shellac as a primer coating to prevent moisture or stains from bleeding through. Shellac can also protect bare wood or paints and wood stains.
Price Tag
Pure and natural finishes, such as shellac, cost more than synthetic finishes, such as varnish.
Level of Thickness
Varnish is heavier and thicker than shellac. That’s because it has a high solid ratio due to its formula’s several compounds and resins. Conversely, Shellac is lighter than varnish because it has more natural than artificial compounds.
Paint Application
It’s more difficult to apply varnish than shellac. That’s because varnish is thicker and heavier, meaning it’s harder to control and apply. The thick nature of varnish also means the finish will reveal brush marks and imperfections when it dries.
However, you can make varnish application easier by thinning it with mineral spirits before applying it. This makes varnish lighter and easier to control and apply.
On the other hand, shellac is easy to apply since it doesn’t have a thick coat. However, you must apply multiple (4 or 5) coats of shellac to properly cover the surface. For varnish, you only need 1-2 coats.
Indoor or Outdoor Use?
Shellac is suited for low-traffic indoor surfaces such as kitchen cabinets, drawers, tabletops, etc. That’s because these surfaces are lightly used, and don’t need much protection.
On the other hand, since varnish is more durable and offers better weather resistance, it can also be used for exterior surfaces. For instance, exterior or spar varnish offers superior moisture-resistant for outdoor surfaces and lasts for a few years.
Do You Need Varnish or Shellac?
Here are a few factors to consider while deciding which wood finish to get:
- Budget – Natural finishes such as shellac cost more than varnish because natural finishes are harder to process and preserve. Also, since shellac is more versatile than varnish, it costs more.
- Moisture-resistance – For surfaces exposed to constant water, use shellac as a finish. That’s because shellac offers better moisture resistance than varnish.
- Wood Protection – Varnish is harder and more durable than shellac. So, for wooden surfaces that will see constant usage, use varnish.
- Indoor or Outdoor – For outdoor surfaces, use varnish and for indoor surfaces, use shellac.
Final Words
Shellac and varnish are two great wood finishes; both will protect the wood from moisture, water, scratches, or other damage. But, since they have different formulas, their qualities are different.
Varnish has a synthetic formula that dies fast and forms a durable and strong coating over wood. While shellac has a natural formula that forms a superior moisture-resistance coating. Because of its superior moisture-resistant qualities, shellac can also be used as a stain-blocking primer.
