Polyurethane and lacquer are two great topcoats that you can use on your furniture. Both of these topcoats are durable and easy to maintain. But, what’s the difference between them?
Polyurethane is a thick sealant that produces a thick, strong, and moisture-resistant layer over the surface. Since it has a thick flow, it doesn’t penetrate the wood fibers.
On the other hand, lacquer isn’t as thick. Due to its light flow, it penetrates porous surfaces, such as wood and plaster easier.
Polyurethane is a polymer that contains polyol and diisocyanates of isocyanate compounds. The reaction of the polyol (alcohol) with the isocyanate or diisocyanates creates the polyurethane finish. In a way, it is a plastic-like sealant.
There are two types; oil-based and water-based polyurethane. Each type has its features, drying time, and strength. But the oil-based type is the most common.
Exterior polyurethane is designed to be used on outdoor surfaces because it has additives that make its finish moisture and UV-resistant. In terms of durability, exterior polyurethane is the most durable type. It has an oil-based nature and a thick flow. So, you must thin it before applying.
You can thin oil-based polyurethane with turpentine or mineral spirits. Water-based polyurethane should be thinned with water.
However, this sealant has one flaw. The sealant tends to yellow over time, which is most common with the oil-based type.
Lacquer is a popular sealant used to finish wood and stains. This sealant has a thin flow, so it’s easy to apply and dries fast. It is durable and has a glossy and smooth finish. Unlike other sealants, lacquer penetrates the surface, giving the finish a stronger grip and increasing its durability.
You can use it indoors where detail is important. This includes shelves, kitchen cabinets, drawers, and the like. What’s common with these areas is that they aren’t heavily used and can be protected with a thin sealant.
However, lacquer has one flaw. The sealant isn’t as durable as other topcoats and won’t last long on outdoor surfaces.
Lacquer vs. Polyurethane: Head to Head
Lacquer has a natural formula and is gotten from natural substances such as tree sap. Also, it contains shellac, which is secreted by the female lac bug. On the other hand, polyurethane has a synthetic formula and is gotten from catalysts, paint chemicals, additives, resins, and alcohol.
The difference in paint formula makes lacquer have a thinner flow.
Lacquer adheres better to wood than polyurethane because it has a thinner flow, and penetrates the surface better. This gives it an increased grip.
On the other hand, polyurethane has a thicker flow and doesn’t penetrate wood fibers as much. This sealant is known to sit over a surface and produce a thick and durable coat. Since it doesn’t penetrate wood much, the paint adhesion is not as strong as lacquers.
Both lacquer and polyurethane are durable finishes and will last about ten years before noticing chipping.
However, polyurethane is more durable than lacquer because it is mixed with different additives that give its finish a plastic-like film. This plastic finish is resistant to moisture, dents, and even heat. In addition, its finish can expand and contract based on temperature changes.
On the other hand, lacquer has a shortage of additives and chemicals, meaning it is easily affected by dents, dust, and chipping.
You must thin polyurethane before applying it because it has a thick consistency, and applying a thick coating takes longer to dry. Plus, an un-thinned coating will be uneven and bumpy.
To thin oil-based polyurethane, use turpentine. To thin water-based polyurethane, use water.
On the other hand, it’s not recommended to thin lacquer as it has a thin flow, and you can apply it without thinning it.
Indoor or Outdoor
Lacquer is thinner and less durable so you must use it indoors only.
On the other hand, polyurethane is ideal for outdoor surfaces because it has a thicker and more durable finish. Exterior polyurethane is formulated with additives that make the paint coating resistant to UV rays. Plus, it has a thick layer that is resistant to water in case of rainfall.
Ease of Application
Lacquer is easier to apply because you don’t need to thin it. Also, it is less likely to reveal brush strokes and dries faster. Since it dries faster, it takes less time for you to complete the project.
On the other hand, you must thin polyurethane before applying it, which takes a lot of time. Plus, polyurethane takes longer to dry (several hours), and there’s a higher risk of ruining its finish.
In terms of paint variety, you have a broader range of paint types and colors to choose from with lacquer. You have acrylic, nitrocellulose, water-based, oil-based, and other types.
Polyurethane gives you a limited variety since there are only two types; oil-based and water-based. But, you can also get a satin, medium, or high gloss finish.
Clarity of Finish
Polyurethane and lacquer are both clear top coats that have no paint pigments.
But, the clarity of the polyurethane won’t last long. After a while, the oil-based type tends to yellow over time. However, the lacquer will remain clear for several years.
Paint Cleaning and Maintenance
Both sealers are easy to maintain. You can wipe stains and dirt off both sealants with a rag and soapy water.
However, polyurethane tends to attract dirt and dust while it’s drying. That’s because it takes longer to dry, giving dust more time to accumulate over the coating.
Lacquer finishes tend to cost more than polyurethane. Though both paints have around the same price tag, you’ll need to purchase more quantities of lacquer because it is a thin sealant, so you’ll need multiple coats to cover an area.
Related Read: Can You Paint Over Lacquer?
Which One Do You Need?
The answer depends on a few factors. Before deciding which top coats to go for, answer a few questions.
- Budget – Though both paints cost around the same, the lacquer finish requires more paint and money. This is due to its thin nature.
- Surface – For indoor surfaces, use lacquer. For outdoor surfaces, use exterior polyurethane.
- Protection Level – If you want to seal a high-traffic surface, use polyurethane because it’s more durable. For decorative surfaces, use lacquer.
Polyurethane and lacquer are both good sealers. However, polyurethane is durable and covers more surfaces with one coat. While lacquer is thinner and dries faster.
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,