When a stacked log wall reduces in overall height, it is called settling, a well known occurrence in log home construction.
Settling in log homes can occur in three ways: compaction, slumping and most significantly, radial shrinkage of the logs.
A- Compaction occurs mainly in log construction using cope style lateral groves where the interior and exterior sharp corners of the cope are the only contact with log below. The cumulative weight of logs, roof and snow above crush these contacting lines of wood fiber into the log below, creating a tight seal between stacked logs.
Compaction can account for up to 1% height reduction of a log wall.
Compaction is minimal for logs with large contact areas like tongue and grooved flat to flat log profiles.