We will be the first people you’ve heard say this: We’re not fans of sealing the cracks and checks in log houses. We will explain why in a bit. But first, let’s understand the challenge.
As logs naturally dry, they get cracks in them. Have you ever split firewood? You set a piece of wood up on its end and look for a crack to hit with your axe, since it will split easiest there. What we see from that perspective is what we, in this context, refer to as checks and cracks.
As the logs swell and contract due to atmospheric changes (much like concrete), the cracks open and close. Now, the logic here is sound. Water is the greatest enemy of a log home. Shouldn’t sealing those cracks be of primary importance to prevent water from settling in the logs?
While we agree that water is the great enemy of a log home, let’s first discuss why it is the enemy. Once the moisture content of wood exceeds a certain point (somewhere around 20%), the brown rot fungus that is responsible for what we call log rot becomes active.
Water WILL get on your log home…a lot. Every time it rains or snows. While we must accept that water will get on your logs, that isn’t really the problem. The actual problem is that the water STAYS on your logs. What we want to achieve is an environment where water can ESCAPE as easily as possible, thus not remaining IN your logs. Generally, this means we want an environment where a wet log can dry as rapidly as possible, with the water escaping in a gaseous form.
Now, back to our first question. Shouldn’t sealing those cracks be of primary importance to prevent water from settling in the logs?
We say, not necessarily. Here’s why.
With these cracks always opening and closing, the sealants will almost always have tears in it. And while it may be 98% sealed, the water finds its way in through that 2% opening… but then it can’t escape fast enough. And it stays damp. And then it rains again. And it gets more damp.
Before long, you have rot setting in in your crack(s).
This may all go against logic. We get that. Know that we are speaking purely from experience. We see more log rot on homes that have done lots of caulking and sealing than ANY other homes. We’ve noticed this trend now for 15 years.
We always tell our clients, “Step away from the caulking gun!” You will almost surely do more damage than you will save. Are there exceptions? Sure, but infrequently.
Contact our office to discuss if your checks need to be sealed and let us know what questions you have!