When it comes to finishing wood, I am a great believer in using shellac and shellac-based products instead of polyurethane-based finishes. Shellac is a natural substance. As a wood finish, shellac has a warm and lovely glow. It is easy to apply and is a less toxic alternative to modern synthetic finishes.
Shellac is the product of an insect. According to Wikipedia: it is obtained from the secretion of the female insect (order Hemiptera), harvested from the bark of the trees where she deposits it to provide a sticky hold on the trunk.
Though shellac is dissolved in denatured alcohol which does produce fumes– these fumes disappear in about fifteen minutes, about the length of time it takes for shellac to initially dry. And when it is dry, shellac is non toxic. For that reason, it is a safe finish for all kinds of furniture and furnishings. Should it chip or wear, it’s residue is not toxic to animals or people.
Today, wooden floors are most commonly refinished with slow drying and terribly toxic polyurethane. Polyurethane is used because it is more long-wearing and durable. In fact, shellac is seldom recommended for floors because it is said to wear quickly. Indeed it does wear within a few months. But the process of refreshing it is so easy, it is as simple as applying liquid wax to a floor. I simply brush it on with a wide brush. I generally do a few boards at a time until the floor is complete. By the time I’ve reached the last board the entire floor is mostly dry. Compare this to having to leave one’s house for at least a day to allow polyurethaned floors to dry and then to endure a lingering toxic odor in the house.
I regard maintaining the shellac finish as akin to a periodic waxing job, and this is apparently quite a traditional approach to tending to wood floors. Elderly friends of mine have told me that in their youth shellac was the most common wood floor finish. One friend recalled that every few months her mother cleared the floors of furniture and renewed the shellac on the floors. I have followed this procedure on my very old basswood floors and found it to work beautifully. In fact, though the old coat has in fact become somewhat dull, I find that each successive coat of shellac creates a richer warmer glow to the wood surface.
There are other shellac-based products that I have found useful in replacing more toxic colored paints. Shellac has an ability to bind to almost any surface. Thus it is used in such commercial products as Zinsser’s B-I-NÃ?Â® Primer, a combination of shellac and a white pigment. I have experimented with mixing colored acrylic pigments into Bin Primer to give me a colored floor paint for some of my wood floors. I did this with some success, although since the colored pigment had a tendency to separate, I had to be vigilant about keeping the color mixed thoroughly. B-I-NÃ?Â® Primer’s ability to bind to a surface of any kind of old paint allowed it to cover my worn patchy painted floors well. I then sealed the floors with a dewaxed shellac product called SealCoatÃ¢Â?Â¢ from the same company, which gave them a pleasant moderate shine. The floors that I painted in this manner resisted major wear for about a year and a half. At that point, I simply painted and sealed them again.
Shellac is a bit more labor-intensive over time than poly-urethane. However, its safety and ease of use more than make up for the extra bit of work it takes to maintain it’s luster on a wood floor.