If you have ever looked into building a log home you are probably familiar with the term “settling”. Settling is simply the compounding effect of logs shrinking as they dry and compressing as they are installed into place in a log structure. Addressing shrinkage and compression is essential for every quality log home.
All wood shrinks from its original diameter to a smaller diameter as the wood dries. Wood is made of long cells that are oriented with the vertical direction of the tree. Due to the nature of these cells trees tend to shrink in diameter but very little in length as they dry. Once the moisture content of wood reaches equilibrium with the humidity of its environment the wood will eventually stop shrinking. In selecting a log product one must consider the moisture content of the material as well as the environment wherein the log materials will be assembled. It is best if your logs are at or below the average equilibrium humidity of the environment where they will be installed. If not you can expect shrinkage as your logs continue to dry after manufacturing. It is recommended to measure the moisture content of log materials at their core to ensure the material is in fact dried throughout the member.
Every type of wood has different compression and bending strengths. Compression is basically how much crushing occurs between the wood fibers as weight is applied. Compression of the actual wood fiber is normally minimal however if logs are not properly installed compounding within the log system may become a significant issue as the logs settle into each other. If logs are not installed tightly together the logs within a wall will eventually settle into place and as they do any space associated with the improper installation is compounded by each course into the overall net settling of the wall and/or the house. We recommend a tightening system that allows you to continually apply pressure to your log wall system as you install it and that will maintain this pressure as the log system acclimatizes and compresses. This will ensure you obtain the maximum compression on your log wall system prior to finalizing construction.
If you are using wood you can expect to experience shrinkage and compression. You can minimize these effects through proper drying prior to manufacture and by using a continuous tightening system to secure your log walls such as the Lodge Log and Timber Thru-Bolt System. Even with these systems you will still need to account for settling over windows and doors, vertical posts, and in framed structures attaching to logs. Minimal settling in these locations can be addressed by providing sufficient settling space and in some extreme cases settling hardware may be used.