Wood is naturally beautiful thanks to the unique patterns of the wood grains. However, wood is vulnerable to moisture effects, heat, and heavy usage if left untreated. Fortunately, most woodworking projects end with a protective top-coat to prevent damage from the above degrading elements.
Polyurethane finish is a commonly used product for protecting wood, whether raw, stained, or painted. Although it gives wood and furniture a beautiful, long-lasting sheen, polyurethane is highly toxic, especially oil-based. So if you intend to protect your wood without suffering the toxic effects of polyurethane, you need to explore polyurethane substitutes.
Many polyurethane alternatives exist, including linseed oil, shellac, lacquer, tung oil, candelilla wax, etc.
Linseed oil is a common and natural alternative to polyurethane. Woodworkers, painters and homeowners use linseed oil in the treatment of wooden structures. It helps wood look attractive and add to it’s overall durability. Linseed oil is a non-toxic product that does not pose any health risk to your kids, pets and even plants.
Keep reading this guide for more information on the subject of discussion.
Table of Contents
What Is Polyurethane
Polyurethane finish is a liquid coating used to protect floors, cabinets, and other woodworking projects from damaging elements. Woodworkers favor it because it is transparent, fungus, water, mildew, and abrasion-resistant.
Unlike other finishes, this protective liquid coating comes in flat or glossy sheens and dries more quickly. Polyurethane goes on with a foam or nylon brush and dries clear.
Application takes 3 to 4 coats, and it’s important to work with thin coats to avoid a cloudy finish. However, thinning polyurethane with mineral spirits can help to address the cloudy finish.
Polyurethane is highly toxic, but you can lower the toxic effects by letting it dry completely before occupying the house. Curing time can take a few days or weeks depending on whether the finish is oil-based or water-based, how much air flows into your room, and how thick you apply the product. The water-based version takes less time to cure than the oil-based.
Alternatives to Polyurethane
Polyurethane finish is the modern variation of oil-based varnish with alkyd binders that dry to form a solid protective layer. This finish comes in different versions, including oil-based and water-based polyurethane.
The oil-based polyurethane is more tolerant of water, making it an excellent option for woodwork projects likely to endure moisture.
Oil-based polyurethane is also handy for protecting wood from mild to moderate abuse. On the other hand, water-based polyurethane dries faster and has fewer VOCs.
Despite these benefits, polyurethane is highly flammable and toxic. Breathing or contacting this product can trigger skin and eye irritation and encourage asthma and respiratory complications.
For that reason, woodworkers are now turning to eco-friendly, natural, and less harmful polyurethane alternatives. This article offers insight into the best polyurethane alternatives. Read on!
A coat of varnish on your woodwork, outdoor furniture, and outdoor decking offers unmatched protection against environmental elements. It comes out more solidly than other protective finishes, perfect for exterior projects. The components in this finish provide wood with UV protection meaning your furniture won’t fade in the sun so much.
- Best Uses of Varnish
The great solid content and low toxicity of varnish make it safe to use near the entryway on trim and exterior doors. High-quality varnishes are flexible and suitable for softwoods like pine that bend under stress.
Despite its ability to form a UV-resistant coat on wood, varnish can peel, crack, or bubble if not applied correctly. Therefore, applying this finish in multiple layers with a natural-bristle brush is advisable for optimal results.
Then let the finished surface stay for 6 hours under fair weather conditions to get professional-grade results.
Varnish dries too slowly and is very difficult to clean. It is also liable to discoloration, dust buildup and is incompatible with water-based products.
Shellac is obtained from natural elements making it safer and a great alternative to polyurethane. It is a versatile and non-toxic finish that enhances the wood grain exactly when adding smoothness without the plastic-like characteristics of polyurethane.
However, shellac isn’t suitable for every piece. This wood finish can fade after long-term exposure to the sun, and it’s sensitive to high humidity and water.
So even though this durable finish can be retouched or repaired if necessary, it’s wise to apply it on surfaces that won’t see too much wear and tear.
Shellac is an easy finish to work with, especially if you apply it correctly. It dries to an orange tint and high-gloss finish. However, you can bleach or mix shellac with extra denatured alcohol to develop a more matte surface. A full protective shellac coat needs multiple thin layers with a little bit of sanding and buffing between coats.
- Pros of shellac
Shellac offers users many advantages, including ease of application. It is suitable for surfaces to which children and pets are exposed. Shellac also dries to a hard shell, and any dents or scratches on its surface can be addressed by applying a fresh coat of this finish.
This finish is commonplace for woodworkers considering it comes in different colors and can be peeled away from wood with alcohol.
There are also some downsides to using shellac as a protective finish. For example, heat is one of the most unfortunate problems with shellac. If you use this finish on wood constantly exposed to heat, it will form white rings making your furniture look unattractive.
Using lacquer on wood gives it a shiny finish making it a perfect replacement for polyurethane. This coating enhances wood character without sacrificing the natural look.
What’s even better? Lacquer dries quickly, meaning you can introduce traffic to lacquered surfaces soon after applying.
Lacquer is a top contender among the best durable finishes. It dries faster, and it’s more user-friendly than polyurethane. It doesn’t require thinning since it’s light enough to spray with any air equipment. This durable coating lasts longer than its competitors, and it won’t chip or flake with time.
You don’t have to apply more than two coats to get a perfect sheen with lacquer. This saves material consumption while minimizing the cost. Best of all, this formula comes in three versions: dull, medium, and high-gloss. Applying lacquer involves minimal exertion, so even beginners will appreciate this formula.
Lacquer is not a durable coating. Any scratch from a sharp object exposes the wood, making it liable to moisture effects. Recoating lacquer also involves too much effort to sand any damaged areas.
This wood finish also has poor resistance to liquids. It can discolor in areas that contact water, salt, or chemicals. Also, if you decide to brush lacquer instead of spraying, you will notice visible stroke marks. However, you can remove these marks with lacquer thinner.
Tung oil helps reveal the wood grain, depth, and beauty of wood. Although not better than other products, the finish soaks into the wood pores and can be a great alternative to polyurethane. Considering this finish has natural ingredients, it is more eco-friendly than polyurethane.
Unlike most wood finishes, tung oil doesn’t form a hard shell on top of wood surfaces. Therefore, you should add a coat of wax to guarantee maximum protection. Tung oil works as a water-resistant coating to keep moisture from penetrating the wood.
Applying tung oil is relatively easy with a paintbrush or a soft cloth but ensure you go along with the wood grains direction for the best results. This will make your wood absorb the finish much more quickly.
What’s even better? Even beginners can use this wood finish provided all steps are followed.
- Tung oil is highly flexible, meaning it won’t crack easily even in harsh conditions. Instead, it contracts and expands with the wood without sacrificing its stability.
- It is a versatile formula.
- Resistant to acids and alcohol.
- It doesn’t yellow as it ages.
- Attractive in color.
- Easy to apply.
- Tung oil is food safe and non-toxic.
Tung oil is very expensive and may not perfectly resist high traffic. Therefore, expect to re-oil your wood projects every three to five years if you choose this wood finishing option.
Tung oil also takes longer to dry, so it’s not a quick DIY project. You may need to apply at least six coats to penetrate the surface completely for this wood finish.
This finish doesn’t smoother the wood grain. Therefore, you must wet sand your surface after each coat to achieve a smooth wood grain.
Linseed oil is also a natural finish and a perfect substitute for polyurethane. It soaks deep into the wood grain to create a solid coat against scratches and moisture. You will also appreciate the satin finish that highlights the color and wood grain underneath once this finish dries.
This durable coating comes in three forms: raw, boiled, and polymerized. Raw linseed is the purest amongst the three. However, sometimes it’s not suitable for wood because it takes time to dry.
Boiled linseed oil is a good alternative, except it contains harmful Volatile Organic Compounds. Polymerized linseed oil is the best as it is pure and non-toxic. It also has a quick drying time.
Linseed oil also comes with a few setbacks, including yellowing as it ages, susceptibility to scratches that are difficult to repair, and it requires occasional re-oiling.
You will also notice some visible water rings if linseed oil is exposed to water. Again, changes in humidity or temperature can cause your wood to bleed oil.
Aluminum oxide offers the hardest and most long-lasting protective coating ideal for high traffic areas. It protects wood from scratches, scuffs, fading, water damage, wear and tear without hiding the grain or sacrificing the wood color. The finish is available in several shine levels than polyurethane.
On the downside, this finish is hard to remove or restore when you want to touch up dents or switch to a different finish. You also can’t apply this finish yourself since it’s only available on prefinished wood.
The acid-cured finish is more productive than polyurethane. Thanks to its durability that eliminates the need to touch up your woodwork often.
It is designed for exotic wood or those with detailed patterns, including parquet flooring. This finish has an alcohol base that dries to create a shiny surface resistant to scuffs, chemical damage, and scratches.
Before choosing this product as a polyurethane alternative, know that it has a strong odor. So when you apply it, ensure your family and pets vacate the room for several days.
Before introducing polyurethane finishes, wax was the best wood floor finish. It remains a popular option for DIYers who fancy its low-sheen and natural look. Wax is available in liquid and paste form, and both require multiple coats to enhance your wood character.
Liquid wax is applied using a wool applicator, while paste wax goes on with a clean rag. You can mix wax with wood stain to color your workpiece as you also protect them from degrading elements.
Be aware that wax doesn’t form a very durable coating. Frequent exposure to moisture can introduce white marks on the surface, so it’s not recommended for kitchen areas.
Wax also scuffs easily, but you can address that issue by adding another wax coat to buff the imperfections. Still, the application process is labor-intensive.
Is there an Eco-Friendly Polyurethane?
Nowadays, people focus on environmentally friendly products to avoid suffering the effects of volatile organic compounds. Products like oil-based polyurethane have synthetic resins and plasticizers that make it a better pick for commercial properties and high-traffic areas in the house.
However, this product has high toxic chemicals that can pose a severe health risk before it cures. It also releases a strong smell that hardly disappears with time.
Fortunately, water-based polyurethane is eco-friendly because it releases fewer VOCs than oil-based and has mild to zero odors. So whether or not there is an eco-friendly polyurethane depends on the version: water-based or oil-based.
Polyurethane Vs. Lacquer
Considering the unattractive consequences of poorly protected wood surfaces, woodworkers search for various wood finishes to preserve their valuable furniture.
Polyurethane and lacquer are two of the popular wood finishes that dry into solid protective coats when applied. Each of these wood finishes has different ingredients and delivers different levels of protection from the elements.
Let’s look at their basics.
Lacquer dries through solvent evaporation when it soaks into the wood, offering maximum protection against breeding bacteria. However, this finish is not much durable compared to other products like polyurethane. But since it’s thinner, it dries very fast, allowing users to apply multiple coats simultaneously.
Polyurethane consists of resin molecules, and it stays on the wood surface to cure to a durable coating.
Difference Between Polyurethane and Lacquer
The main difference between these two popular wood finishes is that polyurethane is a thick liquid coating that dries to a protective layer over a wooden surface. By contrast, lacquer is a thin coating that penetrates deep into wood surfaces to create a barrier against elements. Other differences include:
- Ease of Application
Polyurethane is thicker than lacquer and needs a brush to apply because its consistency can prove difficult to go on with a sprayer. Even though it spreads smoothly with a brush, you might still notice brush marks after applying it. But you can avoid these marks using a natural bristle brush.
With lacquer, you will want a high-volume low-pressure sprayer for optimal results. Such sprayers are expensive, but the payoff is consistent results.
Polyurethane is more durable than lacquer because it contains thicker ingredients and stays over the wood surface. Polyurethane comes in two coatings: water-based and oil-based, whereas lacquer comes in acrylic, nitrocellulose, and water-based.
These wood finishes enhance visual appeal, add gloss to wooden surfaces, and encourage longevity. They are also pocket-friendly, so anyone can purchase them for their upcoming woodworking projects.
Pros of lacquer
- Lacquer is resistant to water and chemical spills and maintains its transparency as it ages.
- This finish doesn’t require special maintenance.
- It is eco-friendly because it is less toxic.
- The quick-drying time allows you to make subsequent coats.
- Lacquer doesn’t yellow or get cloudy over time.
- It has low maintenance, requiring no extra care.
- You can use lacquer in many applications, such as a sealant on metal and a protectant and colorant in the automotive industry.
It is tricky to remove scratches and dents from lacquered surfaces. This wood finishing solution releases a strong odor. However, it’s safe when dry.
Pros of Polyurethane
- Polyurethane is a durable coating that can withstand maximum abuse.
- The coating leaves a glossy finish, thus enhancing visual appeal on substrates.
- It is fairly cheap compared to most finishes.
- It has a chain of resins molecules that bond tightly to form a hard shell when it dries.
- Polyurethane can keep harmful bacteria from eating away building materials.
- This finishing solution is versatile.
Polyurethane is among the most toxic wood finishes. It also takes time to dry and release the strong odor.
Polyurethane Vs. Epoxy Resins
Various ways exist to update floors and other surfaces in your home, but polyurethane and epoxy resin offer the best mixture of versatility and durability. These products come with different characteristics and strengths, but they also have similar characteristics that we will unfold in this guide.
Epoxy is formed when liquid resins are mixed with a hardener. This process creates heat, and the material gets well suited for wood, metal, fabric, concrete, etc. However, epoxy resin won’t stick to greasy surfaces like silicone, wax, or painter’s tape.
You should consider the resin’s thickness before purchasing this formula. The high-viscosity epoxy resin creates a shiny and rich appearance but takes longer to dry. Lower-viscosity resins are easier to apply and dry too soon.
High traffic areas can benefit a lot from the flexibility of polyurethane more than epoxy resins. Polyurethane is also abrasion-resistant, and you can modify it to prolong its lifespan.
Both epoxy resins and polyurethane have minimal resistance to chemicals, but epoxy has greater tolerance to high humid areas.
Polyurethane has better flexibility making it suitable for high traffic areas than epoxy resins. This flexibility also prevents cracks from moving through polyurethane coating.
Polyurethane and epoxy resin are durable coating solutions, but they differ in cost. Polyurethane is more expensive than epoxy, but this price comes with several benefits like enhanced cosmetic performance characteristics.
Epoxy and polyurethane have strong resins to deliver superior protection to various surfaces. You can also add UV-resistant additives to these formulas to make them suitable for outdoor projects.
Another similarity lies in their appearance. Both enhance the visual appeal and offer a robust finishing solution that can last for years.
Pros of Polyurethane
- Polyurethane is heat tolerant.
- Minimal maintenance.
- UV stability.
It is toxic and relatively expensive.
Pros of Epoxy Resin
Epoxy resin is an economical flooring choice compared to polyurethane and other products in the same category. Even better, applying it doesn’t need a complete overhaul, and you can retouch it on existing wood, steel, or concrete.
You will also appreciate that epoxy resins need low maintenance, which adds an advantage in their long-term value. While Its lifespan varies depending on the exposure to elements, location, and purpose, this durable formula is guaranteed to outlast polyurethane. This is especially true if it’s installed professionally.
- Epoxy resin has a wide range of material characteristics.
- It has high mechanical properties.
- Low shrinkage during cure.
- Less affected by corrosion.
It is toxic and gives off strong fumes when applied. For this reason, you should wear a face mask to avoid these odors. You should also apply this formula in a well-ventilated space to avoid suffering the hazards of epoxy fumes.
Since epoxy is non-porous, it is slippery when wet. This can be dangerous if you apply this resin in places children often play.
It’s possible to free yourself and your family from toxic exposure and find various alternatives to the polyurethane that are eco-friendly and safer. Products like linseed oil and shellac are great polyurethane alternatives. They are not too hard on the budget, yet they protect various surfaces from deteriorating without sacrificing efficiency.
Thanks for stopping by this guide, and I hope the solutions here will benefit your next finishing project.