There are several modern finishing products that are suitable for log homes. All of them penetrate the surface of the log and provide a protective film on the surface. A good finish should contain a maximum number of solids, some mildew inhibitor, and Ultraviolet blockers. The Stain and Finish you select for your home will greatly affect the long-term integrity of your logs.
LET’S TALK ABOUT THE NEED FOR A PIGMENTED FINISH
Basic fact here is that using a colored stain can increase UV protection. Logs with pigmented color usually need less maintenance, maintain their color and offer protection from the elements for a much longer period of time. The look of bare wood is nice and bright and can be the ideal color for someone’s vision of the perfect log home. So, what is wrong with applying one or two coats of some type of clear sealer to hold the color of the wood and protect your logs from rain, snow, and ultraviolet (UV) light damage?
UNDERSTANDING PIGMENTED STAIN FISNISH
The colorants or pigments contained in a colored finish absorb UV light and remain active so long as the pigments remain on the surface. It’s the pigments that do the majority of the work protecting the underlying wood from the effects of UV exposure. The purpose of a clear topcoat is to protect the color coats just like the clear coat on a car. In addition to making a car attractive, car paint is designed to protect the underlying metal. The job of the clear coat is to protect the paint. The same concept applies to the exterior finish systems of a log home. The color coats protect the underlying wood, and the Clear Topcoat protects the color coats from the effects of dirt, wind, sunlight and weather. If you want a bare wood look, you can choose a color like Butternut or Wheat. They have the appearance of bare wood but offer the UV protection inherent in a high quality pigmented stain.
DAMAGE & MITIGATION
The most damaging environmental factors to wood are water and sunlight. Water penetration creates conditions conducive to decay while the UV component of sunlight destroys the integrity of the wood’s cellular structure. Technically, we define this UV damage as the photo-oxidation of the lignin. Although clear coats alone can temporarily provide a barrier against water penetration, they have difficulty dealing with UV light for more than a few months. Clear coats rely on two mechanisms to protect the underlying wood from UV light, reflection and absorption. If the clear coat is slick and shiny, it will reflect much of the UV light but as it gets dirty or dull less and less light is reflected allowing more UV light getting through to the wood.
Chemical UV inhibitors may be included in the formulation, but these are sacrificial, in other words the more UV light that they are exposed to, the quicker they get used up. The bottom line is that if only clear coats are applied to exterior bare wood, they provide only temporary protection against UV damage and degrade fairly rapidly so that even their ability to repel water may only last for a year or two. Within a few months the home will end up being multicolored with sun protected areas being significantly lighter than those areas exposed to direct sunlight.
You put so much into your log home to make it beautiful. Make sure that it is protected for years to come by understanding the stain you select and making sure of proper wood preparation and application. There is nothing more stunning than a Log Home stain that is done perfectly with good products and expertise!