A Guide to Healthy Wood Finishes

How Do You Choose a Natural Wood Finish?

Natural wood finishes have been used for centuries and are making a comeback as more homeowners and builders look to use natural, non-toxic products. Look for water-based, oil-based, wax-based, and shellac wood finishes as they contain low to no VOCs and come from renewable sources.

How to Make Homemade Natural Wood Stains?

Mixing up your own natural wood finish is easy and limits waste as you only need to make what's needed. If you prefer to buy a ready-made wood finish, look for those containing no more than 250 grams of VOCs per liter. Green Seal-11 certified wood finishes are easily spotted by their certification logo that promises a limited VOC concentration.

What Is a Water-Based Finish?

Water-based wood finishes are an excellent choice for their durability and easy to clean up with just soap and water. These finishes often contain low to no VOCs, dry clear quickly, and will resist yellowing with time. Some store-bought water-based wood finishes can contain toxic solvents to increase drying time, so be sure you read the label!

What Is a Natural Oil-Based Wood Finish?

Plant-based oil wood finishes penetrate deep into the wood for long-term protection and preservation. Natural oil finishes are low in VOCs. These products have the additional benefits of increasing the wood's richness and translucence without leaving a surface film behind.

Oil-based wood finishes can take up to a week to dry and generally require multiple coats to achieve the desired finish. Some manufacturers include a toxic solvent to decrease cure time, so be sure to check that label. There are a variety of options in natural oil-based wood finishes. Still, most will need to be reapplied every year for the best results. And remember, never use vegetable-based oils like olive oil as these will spoil and take on a stale scent.

It's also important to note that oil finishes are highly flammable. If you do need to heat them, be very careful. Never heat an oil finish that has been mixed with a drying agent like mineral spirits.

What Is a Tung Oil Wood Finish?

Tung oil is derived from the seeds of the tung tree, native to parts of Asia. Tung oil has been used since 500 BCE. This ancient wood finish has the fastest curing time of all oil-based finishes, curing in just a few days.

Tung oil works by coating the wood, soaking in, and then hardening to prolong wood products' life. It is more water-resistant than linseed oil, but it does not protect the wood from scuffing. Natural tung oil does not contain VOCs, but solvents may be added to store-bought tung oil. Be aware; tung oil may affect those with nut allergies.

What Is a Linseed Oil Wood Finish?

Linseed oil is derived from flax seed and cures in a beautiful satin finish with a golden color, becoming more of an amber tone with time. It is an excellent choice for indoor wood, including moldings, paneling, beams, and furniture. It can be used to finish wood floors but will need to be reapplied twice yearly for the best protection.

Linseed oil is waterproof and will protect the wood and prolong its life. Wood treated with linseed oil can, however, still be scuffed. This wood finish does take about three days to dry per coat, so be sure to give your project plenty of time. You will find store-bought linseed oil that has been boiled, heat-treated, or polymerized to decrease dry time, but these contain a toxic metallic agent. Look for raw linseed oil that does not contain VOCs or other additives.

What Is a Jojoba Oil Wood Finish?

Jojoba oil is an excellent choice for protecting kitchen food-contact wood products like wooden spoons, bowls, and cutting boards. It can also be used on beams, framing, garden tool handles, and furniture. Jojoba oil is VOC-free and penetrates deep into the wood to condition and prolong its life, but it can still be scuffed.

Walnut Oil Wood Finish

Walnut oil is another wood finish suitable for food-contact wood products, but should not be used by families with nut allergies. This oil will penetrate deep into the wood, but can still scuff.

Walnut oil requires 3-4 coats for an excellent finish on decorative wood-like beams and moldings and six or more coatings for heavy use wood items like furniture and cutting boards.

What Is a Wax Based Wood Finish?

Wax-based wood finishes are available in liquid, paste, or solid forms. But, only solid products are free from solvents added to decrease cure time. Unlike oil-based products, these finishes are available in a range of colors, including clear, amber, white, and other common wood tones.

Wax-based wood finishes are unlike water and oil-based wood finishes that penetrate the wood. Wax will not penetrate but instead sits atop the wood, providing a protective layer that prevents oxidation (greying) and will shed water and resist spill stains. Wax wood finishes can be applied over another type of finish for double protection.

When applying a wax finish, wipe it off immediately for a dull sheen or let it dry and then buff the surface for a shiny finish.

What is a Beeswax or Soy Wax Wood Finish?

Beeswax and soy wax have various uses, one of which is sealing the wood to extend its life. These waxes are hard solids that need to be melted and mixed with natural oils like tung oil or jojoba oil.

What Is a Carnauba Wax Wood Finish?

Carnauba wax is derived from the leaves of Brazilian palm trees and is more commonly used to wax cars and surfboards. This wood finish is super durable, dulls over time, and won't flake or peel.

What Is a Shellac Wood Finish?

Shellac is made from the secretion of the female Lac bug and a solvent additive. This renewable wood finish is extra hard and durable against scuffing, heat, and moisture. For an even more durable finish, follow up a shellac finish with a water-based sealer.

Shellac can be tinted with color for a unique wood finish and is an excellent choice for protecting wood furniture. When mixed with an ethanol solvent, shellac can be irritating, but the effects will dissipate quickly. Shellac mixed with methanol or wood alcohol is highly toxic and should be avoided.

How Do You Apply a Wood Stain or Finish?

Follow these easy steps to apply your chosen sustainable wood finish safely:

1. Prep it. Wearing a mask and goggles, strip any existing paint or finish and sand the wood down. Brush off all dust with a cloth.
2. Stain it. If you choose to stain your wood before finishing it, now is the time. Allow several days to allow the stain to dry before applying a finish.
3. Test it. Apply your chosen wood finish to a small, hidden piece of the wood first to ensure you're satisfied with the results.
4. Apply the finish. If using an oil or water-based finish, use a paintbrush, foam brush, or soft cloth to apply an even coat. Then, wipe-off any drips. If using a wax finish, apply it with a soft cloth or steel wool. See above for instruction on when to wipe a wax treated surface. Goggles and a mask are recommended to minimize the inhalation of toxins.
5. Let it Dry. Allow the first coat to dry for 24 hours (or the recommended drying time, if it is longer).
6. Repeat. Add additional coats at 24-hour intervals until you are satisfied. Be sure to allow each coat to dry before applying another as color may darken.
7. Finish it. For a smoother surface, use 600 grit sandpaper to lightly sand the oil or water treated surface after drying for 24+ hours. For wax finishes, skip the final sanding. Buff it with a soft cloth for a shiny finish.

When finished with your wood finishing project, be sure to clean up thoroughly. Clean up any excess wood finish product with a rag, soap, and water. All brushes and rags should be soaked in water and then stored in a sealed bag.