Are There Advantages to Using Cordwood Over Traditional Timber Framing?

Advantages in Insulation and Cost

Cordwood masonry construction can provide higher insulation values than traditional timber frames, with reported R-values of R-20 to R-30 per inch of cordwood wall. This is due to the combination of the insulated core (typically consisting of wood chips, sawdust, or other organic materials) and the thermal mass of the cordwood exterior. When using cordwood masonry, builders can achieve similar insulation values to those achieved with traditional framing methods, but at a lower cost. For example, a cordwood wall 8 inches thick can achieve the same insulation as a 2x6 wood frame wall.

Design Considerations and Log End Walls

Cordwood masonry construction often employs log end walls, which can be prone to cracking if not properly managed. To minimize cracking, builders should use a combination of moisture-resistant mortar and a flexible bond beam. A typical cordwood wall consists of a core of insulated material (such as wood chips) surrounded by a layer of cordwood, which is then mortared onto a foundation or bond beam. Builders can use a variety of techniques to minimize cracking, including using a pre-mixed mortar mix with a high proportion of cement, and applying a layer of sealant to the cordwood surface.

Building with Cordwood: A Practical Approach

Building with cordwood requires a combination of traditional masonry skills and specialized knowledge of cordwood construction. Builders should begin by preparing a foundation, and then constructing a bond beam to support the cordwood walls. Cordwood walls are typically constructed using a pattern of alternating layers of cordwood and insulated core material, which are then mortared together to form a solid wall. To ensure durability, builders should use a high-quality mortar mix and apply a sealant to the cordwood surface.