Cordwood construction (also called “cordwood masonry,” “stackwall construction” or “stackwood construction”) is a term used for a natural building method in which “cordwood” or short pieces of debarked tree are laid up crosswise with masonry or cob mixtures to build a wall. Cordwood is a building technique that is richly embodied in sweat equity and labor intensiveness.
The actual physical process of building is not seriously strenuous (the log ends are only between 25 and 40 cm. long), but it does take time and will-power to complete all the walls. The materials for cordwood walls are found in the forest and not in the building supply store, so it is not something one can order and have delivered. It requires planning, perseverance and patience.
Remains of cordwood structures still standing date back as far as one thousand years in northern Greece and Siberia. More contemporary versions can be found in Europe, Asia, the Americas. The exact origins of cordwood construction are unknown. It is, however, plausible that forest dwellers eventually erected a basic shelter between a fire and a stacked wood pile.
Choice of wood.
Choices of which wood to use in building a cordwood house are based on things like local availability, durability, water content, storage facilities for drying out the wood, insulation value, how much water the wood will be exposed to, what type of mortar will be used, which exposure the side will have, how much wood will be needed and its cost. If you must use only wood from your own land, that does limit the decisions.
Rule of thumb suggests the dense woods have the highest rate of shrinkage and light woods are the best insulators. You also need to choose the wood that is least likely to expand if it will be subjected to much direct rainfall, or else plan on covering the exterior with a plaster mix to protect the grain ends from weather.
Ease of construction.
To lay up a cordwood wall, the builder need never handle anything heavier than a firewood log. Mortar is easily mixed in a wheelbarrow. Cordwood masonry makes use of natural, indigenous materials. To further mitigate the environmental impacts of construction, some cordwood builders concerned with concrete mortar’s high embodied energy use a Lime or even a Cob mortar (clay, sand and straw) instead.
Suffice it to say that cordwood is a natural building style of choices and decisions, based on ones personal philosophy and pocketbook. The first choice comes in the form of “Should I do this or not?” The best way to answer this “mother of all cordwood questions,” is to read the available cordwood literature, visit cordwood homes, build a practice building or take a workshop. Once a person has committed to becoming a cordwood owner/builder, the fun begins.