Straw bales stack up for Central Otago sustainable home

Central Otago residents can look at building themselves a better future thanks to a nationwide sustainable housing competition being driven by Otago Polytechnic.

A team led by Otago Polytechnic and consisting of about 50 people from Alexandra, Clyde, Cromwell, Queenstown and Wanaka, has been hard at work since 2008 designing and building a straw bale house as their entry for the 2009 Sustainable Habitat Challenge (SHAC).

The walls of the Clyde house are now ready to go up so everyone’s invited to lend a hand at the ‘bale raising’ in Earnscleugh Road on Saturday 7 November between 9.30am and 4.30pm.

And for those ‘sold’ on the idea of straw bale homes as the perfect solution to sustainable housing in Central Otago, the house plans will be publicly available on Otago Polytechnic’s Centre for Sustainable Practice website so they can download them and start building their own house.

Centre manager Steve Henry, who is also project leader for the Central Otago house entry, says he believes the house will “stack up” well against other competition entries from around the country, which will all be judged late next month.

“Straw bale houses are used extensively overseas, particularly in the U.S. where it’s become a very common building practice in dry climate areas.

“Straw is a great building material option for Central Otago – it’s cheap, natural and provides great insulation for the dry Central Otago climate. Essentially we’re taking a waste product and turning it into a solid, durable, well insulated and easy to maintain home.

“Solar heating and a super-efficient masonry stove will keep the interior warm and provide for hot water needs while keeping environmental emissions to a minimum.

“We want to encourage people to copy what we’ve done so we’re making the house plans available free on our website for downloading by anyone who’s interested.

“The bale raising and open home will be a great opportunity for people to get hands-on experience to see how they can build a better future for themselves and their families. We’d love people to bring their kids and come along this Saturday to help put the walls up,” he says.

For those interested in checking out the house in detail, there will also be an open home on Saturday 14 November from 10am to midday. Otago Polytechnic staff will be on hand to walk people through the house and point out its different features.

Located at 1088 Earnscleugh Rd, the three-bedroom house is built with non-treated timber and straw bales which give it a high thermal mass and insulation up to two times the building code requirements.

Earthen floors, a five-tonne masonry stove, thick earthen plasters and a large central earthen 'mass' wall will act as passive solar collectors, absorbing the warmth of the direct solar radiation during the day and warming the home on cold winter nights.

The masonry stove radiates heat over a long period at a fairly constant temperature and only needs to be lit every few days. It has cold smoke rather than hot which is routed around the home for warmth.

It also features a sauna at the request of the owner Sampsa Kiuru who can’t wait to move in.

Once the Clyde house is finished, Otago Polytechnic plans to build a public display centre dedicated to sustainable building practice.

For more details about the Sustainable Habitat Challenge visit www.shac.org.nz

or for straw bale construction visit www.smarterhomes.org.nz.

ENDS

More information about the Sustainable Habitat Challenge

Nine teams from around New Zealand entered the Sustainable Habitat Challenge (SHAC) earlier this year and have designed and built (or renovated) a sustainable home.

The SHAC teams comprise members from polytechnics and universities throughout the country, with a diverse range of backgrounds such as engineering, building, architecture and filmmaking. They are supported by private individuals and businesses interested in contributing to the challenge.

Key members of Central Otago team include designers Sarah and Ben Johnston, Paula Hugens from Green Bean Engineering Consultancy, and builder Chris Naylor from Alexandra. In 2008 up to 50 professionals and volunteers participated in the design of the house.

The competition will be judged in November. Judges include lifestyle and home improvement TV presenter and builder Dave Cull, Robert Vale from Victoria University, Nick Collins from Beacon Pathway, Maggie Lawton from Braidwood Research and Consulting, and Nigel Isaacs from BRANZ.