Log homes may be site-built or pre-cut in a factory for delivery to the site. Log homes have some characteristics that are very different from conventional homes, and it’s crucial for home inspectors to understand them. InterNACHI has the only course designed to teach home inspectors to inspect log homes. Items specific to log homes include checking for settling and wood decay.
Settling is the loss of wall height over time. It’s one of the major concerns for a log home. Log homes may be built from green logs, which are recently cut logs with a high moisture content. Or they may be built using logs that have been kiln-dried so that their moisture content is no higher than 19%. Some log homes may have been built using logs with a moisture content somewhere between these two extremes. Moisture content is important because as long as logs continue to lose bound water, which is the water contained in the wood’s cell material as opposed to the water in the cell cavities, the logs will continue to shrink in diameter. When logs shrink, the log walls settle, which will result in a loss of height. In a home built with green logs, it’s possible for an 8-foot-tall wall to lose 6-inches in height by the time the home has finished settling. Allowances must be made during construction of log homes to accommodate the inevitable process of settling because a variety of components can be affected. These include but are not limited to the following:
- Doors and Windows
- Partition Walls
- Rigid Conduit
- Screw Jacks
Most home inspectors are familiar with wood decay. Design features that direct runoff onto log walls, especially log extensions at outside corners, will encourage the development of decay. This is decay you can see because it usually appears as dark discoloration. It happens first at log extensions because the exposed end-grain absorbs moisture faster than the rest of the log’s surface. Other forms of wood decay that can occur with log homes.
- Hidden Decay or Voids inside the Log
- Degraded Finish Coatings
- Wood-Destroying Insects
This is why it is important to obtain the services of a certified log home inspector who understands the differences between a conventional home construction versus a log home to ensure that you the homebuyer makes sound financial decisions to ensure your log home will last a life time whether it be your full time residence or a vacation property.