LogFinish (2024)

Logs and log siding come from trees. They are a natural product. The cause of wood rot is a fungi which grows rapidly in the presence of water that is trapped in wood.If proper measures are not taken to prevent rot, nature takes over.

Wood shrinks and expands naturally. This regular occurrence is caused by temperature and humidity. The expansion and contraction causes checks or cracks in the wood. If those checks are upward facing they provide an ideal place for water to accumulate. When water mixes with naturally occurring fungi in an upward facing check, wood rot can result. There are a number of ways to prevent wood rot from day one. Let’s look at each:

1. Controlling water by design is a great way to prevent wood rot. Large overhangs and porches all around will keep water off your logs. If the water cannot get to your logs, rot will not be an issue. Gutters also do a great job keeping water from running off your roof, landing on a deck or patio and bouncing back up on the logs.
2. All wood on your log home should be at least 24 inches off the ground. Make sure you design your foundation with enough height to make this a reality.
3. Treat your logs and log siding first with an EPA registered wood preservative. The typical preservative options are borates such as those found in Shellguard and Shellguard RTU.These wood preservatives are safe to use according to the manufacturers directions and are effective at killing of the fungi that causes wood rot. These products are penetrators and must be applied to bare wood.
4. A different approach to wood preservatives is a log home finish which is also a wood preservative such as Outlast Q8 Log Oil. This two in one product provides a beautiful finish as well as penetrating deep into the wood to kill off fungi. The active ingredient in Q8 Log Oil is Copper 8 Quinolinolate and it is just as effective the borate based product.
5. Another source of log rot is from water getting in around windows and doors as well as at corners and log butt ends. Energy Seal is the solution. Before applying Energy Seal log caulk, always first insert a piece of backer rod. No mater what species you have built your home from, you can rest assured that as temperatures rise and fall your logs will move. The backer rod allows the caulk to expand and contract without tearing.
6. The best way to prevent rot is to keep water out of your wood. This can be done by using a top notch exterior finish on your logs and log siding and regularly maintaining that finish per the manufacturer’s directions. The key is maintaining that finish on a regular basis to keep water out.
7. Logs and log siding are natural products. They shrink and check over time. When upward facing checks appear you should treat them to keep water out. The best way to deal with checks is to seal them up with Checkmate 2. First insert some round backer rod and then apply Checkmate 2 to a depth of approximately 3/8″. For step by step instructions on sealing checks visit LogFinish.com.