Clear Exterior Finishes

Occasionally we get a call from someone with an older log home who wants to “seal and protect” their logs but does not wish to remove the gray patina that has built up over the years.

Typically they think that some type of clear finish can be applied to their home which will keep water from penetrating into the wood and help retard wood erosion due to sun, wind, and rain. The truth is that there is no clear exterior product that will meet their expectations.

First and foremost, we NEVER recommend the application of Advance or any other Lifeline™ product on bare, grayed wood. The grayness is an indication that the surface fibers have oxidized and lost their integrity. They are like the rust particles on an old steel plate. If you paint over the rust with a latex paint, it will not adhere properly and soon peel off. The same thing happens when a coat of acrylic latex finish is applied onto grayed wood. Since it does not have an opportunity to bond to intact wood fibers, it too, can peel off.

On the other hand, penetrating oil or solvent products don’t rely on surface adhesion so they can be applied to grayed wood without the risk of peeling off. The trouble is that these types of clear products last only a few months - at best.

For example, many clear water repellent products consist of paraffin wax dissolved in petroleum solvents. When first applied they may look like they are doing a great job repelling water since water beads up on the surface. However, within a few months the solvents evaporate and the wax gets weathered off. So unless you are willing to treat your home every six months to a year, they won’t do much good protecting the substrate.

So what’s the best advice we have for anyone who is not willing to remove the gray patina on their home? Our answer is to do nothing. Just like rust helps protect the underlying steel plate from further corrosion, a layer of grayed wood helps protect the wood beneath it from additional damage.

Is this the best way to protect your home? Of course not; if you want your home gray you should use one of our gray colored stains. But if you are unwilling to do it correctly by removing all of the gray oxidized wood, applying any type of clear coat is a waste of your time and money. Sometimes less is best.


Last modified on Tuesday, 10 July 2018 21:44