East House and West House are two single-family dwellings, each roughly 70m2 in floor area with an additional semi-enclosed porch area of a further 70m2. They are located in a small village in eastern Cantabria. They were built during 2015-18, with a low cost and low environmental impact, using principally local and natural materials and volunteer labour.
Both houses have a timber frame built with locally sourced eucalyptus timber, harvested less than 2km from the site and used “in the round,” which is stronger, cheaper, and has lower impact than rectangular milled lumber or laminated beams. This structure supports a green roof with rubber impermeable membrane. The roof structure was built first, allowing the rest of the construction to be done under cover regardless of the weather.
The wall foundations were built using brick and stone. All the stone used in the houses was obtained during the earth-moving on site.
The wall and roof insulation consists of straw bales. The walls are plastered inside and out with cob, a mixture of clay soil, sand, straw, water.
The use of wood, straw, and earth as the main building elements means that there are an estimated 12.8 tonnes of carbon fixed in the building envelope, equivalent to the removal of 47 tonnes of CO2 from the atmosphere.
