If you're confused about which finish to choose for your exterior wood doors, you're not alone. There is a seemingly endless assortment, and some only have very slight differences. So, before you make your decision, it's a good idea to get to know these finishes a little better. This handy guide will help you understand which finish is right for your door.
Although there are many types of wood finishes, they all fall into one of two categories: surface and penetrating. Both are exactly as they sound. A surface finish stays at the wood's surface, and a penetrating finish actually penetrates the surface. Surface finishes work well for when you want a thicker appearance, and penetrating finishes give a more natural wood look to your exterior wood doors. Since penetrating finishes do not offer a great deal of protection, they are often used only for interior doors.
Types of Penetrating Wood Finishes:
Danish Oil – This is a common finish used on interior doors. The oil is mixed with some varnish, so it has a bit of a sheen (and is not suitable for food prep surfaces).
Linseed Oil – Of all the penetrating wood finishes, this one is the most popular for use on exterior wood doors. It's also used on exterior wood siding and log cabins.
Tung Oil – Tung oil is sometimes used for exterior wood doors, but it is most often found on interior food prep surfaces.
Types of Surface Wood Finishes:
Lacquer – This is a classic choice for interior wood doors, but it does not provide the level of protection that most people want for their exterior wood doors.
Polyurethane – Polyurethane is among the most popular finishes because it can be used indoors and outdoors, plus it can be tinted to give the wood a warmer or cooler tone. It's also easy to apply because it can be brushed or sprayed.
Shellac – Shellac is an option for exterior doors, but it is not a popular one. It can be difficult to work with because it dries extremely fast. It must be applied with a brush; Shellac can not be sprayed.
Varnish – Varnish is a very versatile choice for exterior wood doors because it can be found in varying levels of sheen and hardness. It can also be brushed on or sprayed.
Grain Filler – Since grain filler has zero protective value, it is usually just applied under a top coat. It does help fill in the grain, though, so you'll have a smooth surface for painting.
Acrylic Urethane – Acrylic Urethane can easily be brushed or sprayed, and it does not have the strong odor that polyurethane does, so it's a popular choice for those who want to finish the wood themselves. It's good for indoor or outdoor projects, and produces a smooth and easy-to-clean surface.
Catalyzed Clear Topcoat – This is generally not part of a DIY project because catalyzed clear topcoats can be hard to apply. It's a two-part process that includes a catalyst, which helps make the surface very durable. Because of the added durability, this finish would be a suitable choice for exterior wood doors or other outdoor projects.
The wide world of wood finishes can be a bit overwhelming, but when you take a close look at the list, you'll notice that there are only a few choices that are designed to withhold the wear and tear that exterior wood doors will inevitably encounter . And here's one final tip: always remember to write down the kind of finish that suits your purposes before wandering the paint aisles at the store to prevent becoming overwhelmed or frustrated during the selection process. Knowing what you need will save you time, energy, and a return trip to exchange the wrong product.