Sealing “Checks”/Cracks in Logs and Maintaining Exterior Wood Timber Elements

It is imperative to keep characteristic normal “checking,” or cracking, of exterior exposed wood timbers well sealed in the Pacific Northwest. Elevated moisture conditions in wood can lead to WDO (wood destroying organism) activity and damage. Open cracks, or ”checks,” which are normal and typically of no structural concern, allow water to penetrate the inside of log timbers and, in so doing, create wet conducive conditions for WDO activity. WDOs, such as beetles, carpenter ants, rot fungus and termites are literally attracted to elevated moisture; keep it dry and they have no interest in your home. Oftentimes, visible damage in exterior log timber elements doesn’t become readily apparent until the timber is substantially deteriorated. I can give countless examples of this from my experience inspecting thousands of homes.

Of course, home inspectors can’t see the interior of timber logs nor can we invasively inspect. A wise home inspector would- even if “checking”/cracking were noted to a minor extent- recommend further invasive inspection of the affected timbers by a qualified contractor to make sure there isn’t substantial damage within. This is why, when inspecting log homes for instance, I always recommend further evaluation by a qualified log home contractor whenever I see cracks/”checks” in logs or visible evidence of ANY water intrusion, water staining or damage whatsoever. Timber log elements are expensive to replace and are very important to maintain!

If you own a log home, or a home with exposed exterior wood timber elements, here are some tips to help you maintain their beauty and function for a prolonged period of time. It’s all about maintenance!

  1. Keep exterior wood elements well sealed. Untreated wood that gets wet attracts WDOs.
  2. Monitor log timbers for normal “checking”/cracking and properly seal when noted. Use the highest quality elastomeric sealant you can afford for reduced maintenance. A borate treatment should also be considered as a preventative measure.
  3. Monitor exterior caulking and “chinking” details, repair when failed or cracked.
  4. Eliminate Earth-wood contact; keep dirt and debris away from timber elements.
  5. Eliminate vegetative contact with timber elements; keep landscaping elements pruned back from the building exterior so
    the building can remain dry.
  6. Consider top- and edge-flashing exposed vertical and horizontal timber elements. Metal flashing details on the tops and edges of exposed timber elements look great and significantly reduce maintenance.
  7. Keep timber cut ends well sealed; cut timber ends tend to “wick” water quickly, are particularly vulnerable and deteriorate first. Flashing cut ends, as above, virtually eliminates the need to maintain and can create a nice aesthetic finishing detail. Use a high quality “end grain sealer” for cut log ends.

In the end, it’s all about moisture! Keep everything sealed and your home’s beautiful timber elements will last a lifetime. Failure to maintain exposed wood timber elements will inevitably lead to costly repairs. Log home contractors and vendors are a great resource on best maintenance and repair practices.

Here’s a link to a blog about log maintenance that might prove helpful and instructive.