Building a rustic home with cordwood construction

Building a rustic home with cordwood construction
Tags: Building Green
October 2, 2011 - Chad Cornette

The ancient method of cordwood building produces beautiful, rustic-looking homes. Like most natural building methods, the tradition of cordwood has a rebirth with the green building movement.

The history of cordwood

Cordwood structures can be found around the world, with the oldest standing ones in Greece dating back nearly a thousand years. In heavily wooded areas, using the scrap wood just made sense.

What is cordwood?

Using what would normally be cast aside for firewood, cordwood looks like a stack of wood you'd have behind your fireplace.

The cordwood is held together with mortar, creating a wall with both insulation value and high thermal mass. The ends of the logs are left exposed.

As with straw-bale walls, cordwood is not typically allowed to be structural and support the wall. Instead, the stacks of wood are used to fill in the wall between the pieces of a structural frame, or as a veneer like like brick, even though the cordwood is incredibly strong on its own.

Cordwood, from 1 to 6 inches across, is stacked up in a random pattern. The finished walls are anywhere from 12 to 24 inches thick.

You can find your own cordwood from a variety of sources, including fallen trees, timber mills, sawmills, and split firewood.

You will need to remove the bark from the wood to prevent water from sneaking into the home. Nearly any type of wood can be used, but the best choice would be naturally rot-resistant woods, such as cypress, cedar or juniper.

The process of building a cordwood wall is a lot like laying rows of brick, but more forgiving. The logs are set with their ends sticking out, and mortar is placed between each piece.

You may be surprised to know that the logs are not treated or coated with anything. The ends are left to breathe naturally. If you like, you can use lime plaster or linseed oil to finish the exterior of the wall.

Cement-based mortar is typically used to hold the logs together, mixed with sand and sawdust to help it bond to the bare logs. Cob mortar may also be used with waterproofing measures taken.