Cordwood masonry is a form of construction that combines the appeal of wood and masonry together. Short logs of wood are stacked up firewood-style in mortar that contains an insulating space in the centre. It is a resource-efficient method of building because it can use so-called junk wood that cant be milled. Log lengths, and therefore wall thicknesses, range from 8 inches (200 mm) to 24 inches (600 mm). If cob is used for mortar, cordwood masonry can be a very inexpensive mode of wall-building in forested regions. Insulation costtypically for lime-treated sawdustis also fairly low. Cordwood masonry walls have great environmental appeal because they combine properties of insulation and thermal mass. They also have great aesthetic appeal, combining the warmth of wood with the texture of fine stone masonry. Experts are uncertain about cordwood masonrys origins, tending to feel it had multiple independent origins. Historical remains have been documented in Siberia and northern Greece around 1000 A.D. North American findings date back almost that far