BaleHaus Green Buildings

British company modcell is attempting to create more “green,” housing with the use of straw cladding panels in construction and has created a new project - The BaleHaus - A domestic “carbon bank.” It seems a practical approach to us, but whether this idea takes off and is as environmentally friendly as it appears remains to be seen, and according to their website:

Living more sustainably requires us to develop ways to:

1. live within our environmental means - especially in relation to our carbon footprint;
2. maintain a healthy and comfortable quality of life;
3. build strong communities.

BaleHaus addresses these three challenges in a number of ways and offers a straightforward and practical way to reduce our footprint on the earth, without the need for an “eco-guilt trip”.

A Lifetime of Low Carbon

The BaleHaus uses ModCell Straw cladding panels, to provide a super-insulated home, made from locally available materials that are designed to be dismantled, re-used and recycled at the end of a typical 75+ year life. This super insulating system meets the PassivHaus specification for zero heat homes.

A conventional house designed to today’s Building Regulations will emit ca. 3.1 tonnes of CO2 per year. The BaleHaus, however, reduces its heating demand by 80%. It does this through the super-insulation provided by ModCell, high performance triple glazing combined with airtight construction, passive design techniques and heat recovery ventilation in winter. A BioMass boiler combined with a solar domestic hot water system to each house supply the remaining heat requirement for water heating. Energy efficient electrical fittings and appliances in combination with passive design and good daylight levels reduce the electrical demand by 19%. These measures mean the Balehaus’ carbon emissions are reduced to 1.6 tonnes per year, a saving of almost 50%.A “Carbon Bank”

A reduction of 50% in carbon emissions from 2006 standards, while more than meeting an individual’s personal Kyoto target (requiring a 60% reduction from 1990 levels by 2050) still doesn’t meet the brief for a zero carbon house.

The BaleHaus has an additional feature however that allows it to become a carbon “bank”. Straw and timber are renewable resources that can provide a continuous renewable supply of building material, replacing high embodied energy (i.e. “CO2 generating”) materials such as steel and concrete. As straw and timber grow they absorb CO2 through photosynthesis, keep the carbon atom to make cellulose and give the oxygen atoms back to atmosphere. This is how we “bank” the carbon into the structure and fabric of each BaleHaus.

This process “banks” the equivalent of 130 tonnes of CO2 per house to deliver a less than Zero Carbon Home before any one moves in. Even allowing for the ca 70 tonnes of CO2 emitted during manufacture, supply and installation of the building fabric, structure, fixtures, fittings decoration mechanical and electrical equipment, this still leaves 60 tonnes of carbon in the “bank”.

This “carbon credit” is enough to offset 10 years of BaleHaus’ energy requirements using fossil fuels and over 40 years if energy is supplied from renewable, grid-based sources.