Log home inspection: Disclaim the logs?!!!

By Kenton Shepard

When it was time to renew my E&O insurance and my provider told me they were requiring inspectors to disclaim the logs in log homes, I was shocked. They were forbidding me to give my client information about the most important system in the home! I'd like an explanation, Bob...

It was a short explanation. There are many courses available to teach people to build log homes, but none to teach inspectors how to inspect them. Inspectors didn't even know what they didn't know. Most still don't. Allen Insurance was force to buy three homes because inspectors had missed widespread, severe wood decay hidden within the log cores.

I set out to learn log home inspection and after talking with Bob, the first order of business was researching wood decay fungus.

WOOD DECAY

Wood decay is caused by fungal activity. When moisture levels rise above about 20%, wood decay fungus become active. When levels drop below 20%... activity stops. It's that simple. Dry wood does not rot. The term "dry rot" is an oxymoron . Here's a quick run-down of what I learned...

•·         Log species and seasoning methods both play a part in how badly logs check (crack). Checks on the upper surfaces of logs will trap moisture, encouraging decay.

•·         Certain design features can funnel runoff to areas of the home which can trap moisture, or can hold moisture such as snowdrift against the home. Inspectors must learn what to look for.

•·         The type of finish applied to logs must allow moisture vapor to pass though. A waterproof finish will trap moisture inside the logs. If that moisture level is above 20% at the time the finish is applied... BAD THINGS WILL HAPPEN!

I use resonance testing to help locate areas I suspect may hide decay. To document areas of decay I use a $4000 instrument called a resistograph which records decay levels on graph paper.

DIFFERENTIAL SETTLEMENT

As logs lose moisture, they shrink and settle. A home built of green logs will settle like you wouldn't believe! An 8-foot tall wall can lose 5 inches of height during the first several years. If provisions aren't made to accommodate this settling during building, in a very short time problems will begin to appear.

Doors will not swing. Windows will break. Stair treads will no longer be level. The home will begin to hump like a PBR rodeo bull about to explode from the chute. Mossy Oak Mudslinger and a home are two separate entities and they should have nothing in common. Homes must be designed to minimize variations in the amount of wall shrinkage.

If a home is poorly designed or built without methods which accommodate shrinkage and the resultant settling (some of these things are hard to confirm after the home is built)...BAD THINGS WILL HAPPEN!

DIFFERENT TYPES of LOG HOMES

There are log homes still standing in Russia which are in the neighborhood of 400 years old. Homes have been built of logs using every conceivable method, and although in the last 20 years the industry has seen increased standardization, don't put too much faith in that word!

Typically, each builder has a custom catalogue of homes which may or may not be designed by an architect, and proprietary engineering, meaning that each builder does pretty much what they want. They usually each want something different. For around $50 each of the many, many builders will provide a construction manual offering varying amounts of information and details about how the home should be properly constructed, but not many inspectors will shell out the money for a big library of manuals. I know I won't.

As a carpenter I worked on log homes. When I see them being built, I often stop and talk to the builder. I talk with manufacturers. I take seminars offered by product manufacturers. I have relationships with log home restoration contractors. I research log homes online and through organizations like the National Park Service. I have a library of photographs and I spend a lot of time looking at log homes to see how they fail. I've inspected homes built as far back as 1897 and as large as 10,000 square feet.

I helped review the Log Building Standards for the International Log Builder's Association and wrote an exam for them.

There is now one course available to teach inspectors to inspect log homes. It's in Canada. I've been asked by the National Association of Certified Home Inspectors (NACHI) to develop an online course for inspecting log homes but that will have to wait its turn in the project line.

To learn more about log homes, check out my Log Home Basics article (also on the EcoBroker and NACHI websites) and feel free to contact me if you have questions about a home.