Cordwood construction
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Cordwood construction is a term used for a building where 'cordwood' or firewood-length pieces of un-lumbered trees are used in wall construction with mortar between the lengths. The pieces of wood are placed such that the two ends are free of mortar. Walls are often between 18 inches and two feet thick.
Examples of this construction style can be found throughout Europe and North America, with small growth in Central America and South America. It's estimated to be a third of the wall-building cost of standard stick-frame construction and generally has a much higher insulative value (mostly due to wall thickness). Western Redcedar is the preferred wood for this construction as it is highly resistant to rot and insects.
Walls are usually constructed such that the pieces of wood are 'proud' of the mortar by a small amount (an inch or less). The mortar does not exist throughout the wall, as heat transfer would cool the interior dwelling spaces. Instead, three or four inch 'beads' of mortar on each side of the wall provide stability and support. The central space is insulation filled, with many modern builders using a mixture of sawdust and hydrated lime (not agricultural lime).
Roof support can be provided by the cordwood walls or by post and beam construction.