Cordwood construction is the process of building a wall out of stacked cordwood-just like fire wood-with the exception that mortar is set between the pieces of cordwood to secure them in place. This amazing beautiful and ancient technique for building utilizes smaller logs that would be unsuitable for conventional log cabin building. Curved walls, unique as each individual log, makes for exciting design opportunities that are both economical and practical.
While cordwood construction looks as if it’s supporting the walls up, many times, they are not. A basic frame and roof system are built first, then walls are backfilled in, similar to brick home construction. Although a cordwood wall could support some roofing structures, many local building codes prevent that from happening.
Since the roof goes up first, it is very easy to work on cordwood walls in all kinds of acclimate weather conditions. A complete mortar or cobb mixing station can be set up under the cover of a dry roof. This makes cordwood building techniques a first class all-weather project.
Cordwood construction contains another unique element. As cordwood is cut to whatever thickness you want the wall, a cavity is created between the two opposite sides of the masonry walls. Insulation is then able to be placed in between the two walls, creating an R-factor that is incomparable to conventional wall building insulation.
To further the green factor as well as the R-factor, use cobb masonry. Cobb is the use of mud, straw and Portland to create an adobe like cement that bonds just about to anything and is very simple to make.
One of the most common misconceptions of cordwood construction is that the ends of the logs rot. If you build your roof overhang out to 24″, keep all cordwood pieces off of the ground 3′ and build on a solid foundation like stone or block, rot will be impossible. Use rot free logs with no bark and avoid wood on wood contact to avoid future problems with rot.