Wood is an amazing material. Whether it’s in a modern, contemporary house or a classic, period property, it adds beauty and elegance to our homes.
Even so, wooden surfaces need to be protected from the effects of wear and tear, which is why wood finishes are so useful. With everyday use, wooden furniture can become worn and dull from knocks, scrapes, greasy hands, and even from years of being polished.
Sometimes the surface of the wood needs revitalising to restore its natural look and beauty. While some people paint wooden surfaces, others prefer the appeal of the wood grain. Painting hides this quality, which is why we often turn to different types of wood finishes that allow the natural appearance of the wood to shine through.
However, choosing the right wood finish can be a real chore. There are so many different types of wood finishes that it gets confusing. Which one is best? How do you make sure it’s the correct one for the wood in your home? Which finish will give the best result? How do you apply them?
If this is something you’re struggling with, our no-nonsense guide to wood finishes is exactly what you need!
We’ll go through all the different options here to help you decide which is the best one for you.
What Types Of Wood Finishes Are There?
Basically, there are two types of wood finishes: surface finishes and penetrating finishes. As you can guess, one coats the surface, while the other penetrates deep into the wood grain.
Within these two categories, there are several different options. We’ll examine these finishes to explain exactly how they work, how they are applied, and look at their pros and cons.
Most wood stains are fairly easy to apply and you can usually handle this job yourself. You need to apply multiple coats using a good-quality brush to get the best results, but this should be achievable for anyone with even the most basic DIY experience.
The difference between these and some other wood finishes is that they are best used to change the tone of light-coloured wooden surfaces. That is, the stain should be darker than the wood it is covering. This is handy when there are inconsistencies in the appearance, as a good wood stain will hide these and bring out the grain.
One of the best things about wood stains is the variety of colours available. However, you can’t cover dark wood with a light-coloured stain. The final colour will depend on the number of coats applied.
On the negative side, many wood stains don’t offer much protection. After the final coat is applied you will need to cover this with a sealer to provide a protective finish. Without this, your wood surface will be susceptible to damage from spills, greasy fingers, and sharp items being dropped onto it.
This wood stain is a popular choice because it is safe, easy to apply, and doesn’t give off toxic fumes. These stains are also low-odour, which makes them safe for interior use in confined spaces.
As well as being environmentally friendly, they are quick-drying (about an hour) and have excellent coverage. They also penetrate the wood effectively and provide even colour across the surface.
Other benefits include the fact that these wood stains are highly resistant to mould and mildew, and they can be used on any type of wood, whether inside or outside, new or old.
This wood finish can be applied using a foam pad, natural bristle brush, or a cloth.
Solvent-Based Wood Stain
Solvent-based stains are easy to apply and give a smooth finish.
One downside is that you’ll need a solvent like white spirits to clean down your brushes, hands, and any other equipment you use. Water-based products require only soap and water. Drying time can be a problem, too, as they can take between 2 and 6 hours to dry enough to apply the next coat.
Also, these wood stains can be high in VOCs, even up to 75%. This is not only bad for the environment but will also leave a lingering smell of fumes in your home. This is potentially hazardous, especially in confined areas.
This is a traditional wood finish that has been used for hundreds of years. Even so, there are many more products available, some that only contain a small amount of wax as well as a range of additives. For a true wax finish, it’s best to keep it as simple as possible.
While pure beeswax was once thought to be the best option, it doesn’t provide the protection that you get from other finishes if you use it on furniture, so you might want to consider a ready-made brand of paste wax.
Wax finishes are ideal for wooden items that aren’t handled much, but they aren’t the best choice for outdoor furniture as they can be dulled by the sun. It can also be applied over the top of an existing finish to give an extra shine.
Shellac is a natural resin produced by the female lac bug, found in India and Thailand. The bugs eat the sap from trees and secrete resin and wax that forms tubes along the branches. These tubes are harvested and heated over a fire to dissolve the resin into liquid form. This is dried on flat sheets and broken into flakes.
The colour of the shellac is determined by the sap of the tree, with colours ranging from blonde to garnet.
Traditionally, shellac was extremely useful as a safe, non-toxic, natural plastic. Because of this, it had a wide range of applications including dentistry, gramophone records, the motor industry, and ballet shoes!
More relevant to our guide, shellac was (and is) used as a primer for wooden surfaces because it prevents penetration from water vapour. It is also great at sealing odours connected with fire damage.
Finally, as shellac is compatible with most other types of wood finishes, it is used as a primer to stop pigments or resins bleeding into the final finish, or to prevent wood stains from becoming blotchy. One other benefit of shellac is that it provides UV protection, so it won’t darken over the years. However, the wood beneath may darken over time, especially if it is a light-coloured wood such as pine.
Although many people refer to shellac as French-Polish, this isn’t correct, strictly speaking. Shellac is a substance, whereas French Polishing is a method of applying it. The confusion is probably due to the fact that some products are sold in liquid form ready to use. Most (if not all) professional French Polishers prefer to make their own mix using dry flakes.
Oil finishes are one of the best methods to preserve the natural appearance of any wooden surface. Over time, the natural oils within the wood begin to dry out, and oil finishes are a great way to restore and preserve the wood. There are several different oils to choose from:
This is a natural drying oil, meaning that it polymerises when it mixes with oxygen to form a hard-wearing, water-resistant surface with a semi-gloss finish. Danish oil is made by combining Tung or Linseed oil with various types of varnish. It is ideal for hardwoods and can be used indoors or outdoors, making it great for garden furniture. One of its best features is that it has a drying time of between 4 and 6 hours.
Also known as China oil, this is produced from the nut of the Tung tree. It is often considered an environmentally friendly option as it is natural and contains no VOCs (volatile organic compounds), although it is always best to check the contents as some products are sold as Tung oil but may contain solvents, other oils, or varnishes. Some products don’t contain actual Tung oil at all! This oil is particularly resistant to mould and provides a flexible, durable finish.
One drawback is the drying time. Although touch-dry in about 24 hours, it can take between 5 and 30 days to cure completely, depending on the air temperature. 100% pure Tung oil takes longer to dry than products that have been diluted with solvents. This oil has a matt finish that darkens the natural colour of the wood.
Raw Linseed Oil
This is the purest form, without any chemical additives or preservatives. Linseed is a natural oil extracted from flax seeds and is often used in paints and varnishes to give them a smooth finish. It is easy to use and generally more affordable than some of the other options.
One downside is that this wood oil has a lengthy drying time, taking around 3 days for each coat. It’s best to use this oil on bare or previously oiled wood, as any varnish or wax will stop it from penetrating the grain and sealing the surface.
Boiled Linseed Oil
Confusingly, this isn’t boiled! However, hot air is passed through it and it is treated with additives that allow it to dry quicker. Even so, it can still take up to 24 hours. It provides a satin finish that darkens over time. As with the other oils, this penetrates the grain to provide real protection and is water-resistant, without forming a film, unlike varnishes and some wood stains.
This is another misleading name, as the oil is not extracted from Teak, as you might expect. It is called Teak oil as it is intended for use on Teak wood. Most manufacturers have their own blend of oils and varnishes that they market as Teak oil. These usually contain a mix of Linseed and Tung oils with various thinners or varnishes.
Although eco-friendly products are available, it’s always best to check the contents thoroughly. Some brands contain substances that are hazardous to humans and animals. They may give off toxic fumes and ingesting even a small amount may be harmful, if not fatal. Teak oil is not food-safe, so it can’t be used for chopping boards or anything that comes into contact with foodstuffs.
Teak oil is very water-resistant and dries within 4 to 6 hours to provide a matt finish.
A Word Of Warning:
Rags that are soaked in any of these wood oils must be disposed of carefully! As the oil is exposed to the air it starts to oxidise, generating heat. A crumpled rag provides insulation and allows the heat to build up, and this can spontaneously combust.
The entire process can take as long as three hours, and if other solvents are in the vicinity they will ignite. Oily rags should be laid out flat to dry on a non-combustible surface, or soaked in water in a sealed metal container. They can then be disposed of at a hazardous waste facility or placed in with your usual waste as long as you are certain that they no longer present a fire risk.
Each of these different oil wood finishes is pretty easy to use and generally require three coats when used on bare wood. All of them are excellent for enhancing interior wooden surfaces and wooden furniture, bringing out the beauty of the natural grain. Superficial scratches can easily be fixed with a local application of oil.
Essentially, varnishes are paints without pigment. Many are solvent-based, such as polyurethane varnish, containing three basic elements: varnish oils that harden on exposure to air, resin to add strength and body, and thinners, a solvent that makes the product easier to apply and which evaporates, allowing the varnish to cure and harden.
Most are clear or have a slight tint to them and they are available in satin or high-gloss finishes.
Acrylic varnishes have become more popular these days as they are water-based and more eco-friendly.
One benefit of wood varnish is that they don’t usually require a primer or undercoat. If required, a varnish can be applied over a wood stain to provide extra protection.
French polishing is a traditional method of wood finishing dating from the 18th century, using shellac and denatured alcohol. To avoid confusion, as we already mentioned shellac above, French polish is not a product but is the method of applying multiple layers to get the desired finish.
It requires skill and precision to get the best results and is best left to the professionals. If you do plan to tackle this job yourself, it’s wise to make sure you have all the tools and equipment. You’ll also need plenty of space to store the item safely while the wood dries.
The procedure itself sounds simple, but it takes time to master. Here’s a basic outline of the French Polishing process:
Shellac flakes of the desired colour, denatured alcohol (such as methylated spirits), sandpaper in various grit sizes, polishing ‘rubber’ or rubbing pad (wool or gauze tightly wrapped in cotton fabric), tack cloths (cheesecloth impregnated with beeswax), Linseed or mineral oil, polishing mop.
This is essential to the success of the project. The wood surface must be stripped of any old varnish, wax, or polish. The entire surface should be rubbed down with a fine abrasive paper. If the surface has an open grain and you desire a high-gloss mirror finish, a grain filler will need to be applied. The other alternative is to use extra coats of polish and rub them down with ultra-fine steel wool.
You’ll also need to mix your polish. Generally speaking, 250g of shellac flakes to 1 litre of methylated spirits is a good starting point, and then you can add more of either to thicken the mix or thin it out.
Use a glass jar with a secure lid and keep the mix away from naked flames as it is highly flammable. You can shake the jar every so often to speed up the process, but you need to allow about 24 hours for the flakes to dissolve fully. Alternatively, you can use a premixed liquid from a good DIY store.
Make and Load The French Polishing ‘Rubber’
Wrap a square of lint-free cotton cloth around some wadding made of clean scraps of wool, gauze, or cotton. Pour a small amount of the polish mix onto the wadding. Bring the corners together and tie them to form a pear-shaped rubbing pad, making sure that the base is flat and free from creases.
Squeeze the rubbing pad to bring the polish through to the surface. If there’s too much, squeeze some back into the jar. If there’s not enough, then add some more. A properly loaded rubber will glide across the surface easily without leaving too much polish. Circular or figure-of-eight strokes should be made along the grain and should start by sliding onto the surface from one side and off of the other. Try to avoid placing the rubber directly on the wooden surface as this will leave a mark that’s hard to get rid of.
If the rubbing pad drags, then you either need to apply less pressure or squeeze the pad to push through more liquid. Once you have passed the pad over the surface several times, it may start to stick anyway. If so, add a few drops of oil using your fingertips, and this will allow the pad to glide more easily.
After a few applications, allow it to dry for a couple of hours before adding more. It is also advisable to rub the surface down using 320 grit sandpaper or 0000 fine grade steel wool.
Once the required number of applications has been reached, a new rubber should be loaded with a 2:1 mix of shellac and denatured alcohol. This is then used in exactly the same way as before, using circular motions along the grain. Finally, pour a 50/50 mix of shellac and alcohol onto the pad and use quick, light movements across the surface to remove any spots and produce a pleasing finish.
Any decorated areas that you can’t cover using the rubber should be coated using the polishing mop. The same principle applies to the rest of the process, and strokes should be light, never allowing the mop to stay in one place.
If a mirror finish is desired, leave the item to dry for a week or so, then go over the surface with an ultra-fine grade steel wool. Any dust should be removed using a tack cloth. The surface can then be brought to a high-gloss sheen using a branded burnishing cream.
If a mirror finish isn’t your thing, you can achieve a softer sheen by leaving the item to harden for several days before rubbing it down with the steel wool. You can then apply a wax polish to create a softer look.
When done properly, the results are stunning! The secret lies in the fact that many layers (usually more than 100) are added to form a thick, protective layer with a glossy finish.
This finish is ideal for everything from your coffee table to your prized ‘heirloom’ wooden furniture, antique restoration, or musical instruments.
Wood dye offers the advantage of changing the colour of your wooden object completely. You can still choose from a range of colours that resemble natural wood grains. However, there are also blues, greens, reds, and oranges that will add a real splash of colour to your wooden fixtures, fittings, and furniture.
Wood dyes are similar in some ways to wood stains. They can be easily applied by brush and it’s a fairly straightforward process. Most will be touch-dry within 20 minutes and ready for another coat within 2 hours.
The main difference between a lacquer finish and wood varnish is that lacquers are harder and more durable. Also, lacquers are always solvent-based and can be applied using a spray gun as well as painted on by brush.
The main negative point about lacquers is that they are highly flammable, and using spray equipment can be a messy process. It also needs a great deal of precision to get the desired results.
However, it is quick to dry and provides an amazing finish.
Which One Is Best?
Each of these different wood finishes has its own benefits and drawbacks. Your choice of wood finish will depend on the job in hand, whether you are tackling this yourself, and whether you prefer a more environmentally friendly option. Always be 100% certain before taking on the job yourself, and use professionals when possible.
With the right choice of finish, your wooden surface is going to look fantastic.