As the final beauty treatment for your hardwood floors, finishes are substances that are applied to wood planks after these are stained. They create a protective coating and preserve the beauty, color and integrity of the wood. The type of finish used on your wood planks defines the look and the durability of your hardwood floors.
While many wood flooring products arrive to your house already finished, a basic understanding of finishes never hurts. First, it ensures that you properly take care of your floors, according to what is appropriate for your finish. Second, it is essential if you want to refinish the floors yourself and need to remove the old finish and apply new coats.
Finishes can be classified following different criteria. Here is only a handful. Are they sitting on top of the wood or are they absorbed into your planks? What are they made of? What is their level of toxicity? Are they environmentally friendly? Are they flammable? Do they change color? Are they easy to apply, fast to dry or unforgivable with mistakes? Once they are applied, how fast can you step on them? How bad do they smell? And most of all, how do they look? Do they offer strong protection for your floors? And why are they so many?
Luckily, over time, some of these finishes have fallen out of favor changing the spotlight to a few options trusted by both home owners and hardwood floor professionals and making the decision easier. This is why, when talking about wood floor finishes, the discussion often comes down to choosing between types of polyurethane. But polyurethanes deserve their own page. Aside from them, here is a round-up of the most commonly used wood floor finishes that are still used on a small or large scale even with the advance of polyurethane.
Shellac is a surface finish, which means that it is not absorbed into the wood, but dries on the surface forming a protective coat. It claims the prize for the most eco-friendly wood floor finish. It is made of lac, a resin secreted by the Lac beetle from India and South-East Asia. The resin is removed from tree branches, dried and later mixed in varied quantities with ethyl alcohol. The fact that this resin comes from a sustainable, self-propagating source makes shellac an attractive option for environmentally-minded home and business owners.
The lac component is shellac is also food-safe, which is a rare occurrence in the world of hardwood floor finishes and puts it one more step up the stair of eco-friendliness. It has a minimum amount of wax, but this is often removed to obtain the dewaxed shellac and allow for mixing with other products, such as stains.
Even though polyurethanes have stolen much of its spotlight, the appeal of shellac is still there: it has a quick drying time, it sticks very well to the floor so it does not need sanding between coats and it has no smell, even if VOC fumes are still released. On the downside, it still requires a good hand to apply in order to obtain a uniform look, and its flammable formula calls for preventive measures during application. For the homeowner, it is a cheap option that does not yellow and allows for quick and easy fixes, but the protection it provides is inferior to polyurethanes: the coat is less durable and prone to water stains. Ammonia and alcohol are also its enemies, so extra care is needed when you clean your other areas of your house or when you reward yourself for doing it.
Somewhere between shellac and polyurethane finishes in terms of durability, varnish is fast losing its old grip on the hardwood floor industry. Its claim to glory comes from the fact that can be mixed with stain, thus achieving in one step both the staining and finishing of hardwood floors. However, it takes more time to dry, and requires careful application, sanding between coats and protection from the strong VOC fumes. A surface finish itself, varnish in inexpensive, but there are better products in terms of resistance to wear and tear.
The history of hardwood floor industry is littered with fatal accidents caused by lacquer, so this surface finish, while giving you beautiful looks and gloss, is slowly disappearing from the wood flooring landscape. The reason is the extreme flammability of this formula. The flammable solvent takes about 80 percent of the mix and has caused enough explosions, death, injuries and property damages to make the centuries-old appeal of this finish seriously wane. While there are water-based lacquer finishes on the market, they come with a steeper cost.
The advantages of lacquer finishes are still attractive enough for the few wood flooring contractors that still use it as a sealer. Lacquer has one of the fastest drying times in the industry and is sometimes ready for a new coat in a matter of minutes. Along with the fact that it is very forgiving with mistakes, this makes one-day applications possible. However, even if hard enough, its durability is inferior to modern finishes.
The main attribute of penetrating finishes is that they are absorbed into the wood, filling its pores and thus waterproofing the wood from inside out. They do not leave a film on the surface, so they are the best at showing the natural beauty of the wood. Keep in mind that it also shows wood imperfections, so your hardwood floors should be in good shape and well sanded before application. The lack of a surface film helps the wood adapt easier to changes in temperature and humidity, which minimizes warping.
Some of the penetrating oils used for sealing hardwood floors are tung oil and linseed oil. They are generally easy to apply, but they require constant maintenance in the form of new coats. However, you can easily fix damaged areas and regain the luster of the floors with another coat or fix damaged areas. While penetrating finishes do not provide the same durable protection as polyurethane, they are low in VOC fumes and are seen as a more eco-friendly option.
The traditional way of sealing and giving luster to hardwood floors, wax penetrates the wood pores and creates a protective coat on the surface. Wax is very easy to apply, both as a paste or as a liquid, after which some buffing is required. Wax can also be combined with stain.
A formerly waxed floor can be easily re-waxed or touched-up, but you may end up doing this too often for your taste. Wax requires periodical recoating, a perfect job for the enthusiast DIY-er. In addition, this finish tends to whiten at the contact with water. Finally, wax may yellow over time, does not give your floors the professional look of a surface coat, and the protection is far below polyurethane.