“Whenever I drive past a new building on the edge of every town, I wonder — why aren’t they building straw bale? But the word is spreading, and staw bale buildings are becoming a more common sight around the world. Want to take a little tour?”
“Learn how David Fortin, architecture professor at Montana State University, and his student Michael Spencer researched solutions to a housing shortage in Kenya for three years. This past summer, they worked on building straw bale structures in the east-African country. This summer they and a team of MSU students will build six to eight houses made from straw-bales in Ex-Lewa, a farming area of central Kenya. The 30-by-15 foot storage building that Spencer helped build last summer that holds 20 tons of potatoes cost about $2,000, or one-fourth less than what it would cost if it had been built of traditional stone or wood-frame construction. Spencer said. “There is already a long waiting list of people interested in straw-bale structures. I could work full-time for the next two years just on building straw-bale houses in Kenya for current clients who want houses like this.”
I live and work in Kenya and would love to build a straw bale house. Are you currently building homes here or do you have any suggested contractors that are familiar with the process?
No, you’ll probably have to figure things out using books and online resources. One good resource is Matt’s Myhrman’s free strawbale book. Search our blog and you can find the story and the link to his free PDF.
Oh, I forgot, I’d lay the keystone row as a vertical bale, alternating from either sides second to top row. And with the cattle panel permanent interior formwork embedded in a quality lime or clay plaster, along with appropriate exhaust and attention to detail, I’d think this breathable vault would last a long time. If someone does this, let me know how it works out before I do it :)
Thanks. I like the idea of adding a roof to strawbale vaults in rainy/snowy climates for added protection.
I had been thinking about strawbale vaults a bit ago. here IsIs what I came up with (from inside out):
$20 cattle panel, 4.2’x16′ 6 ga, with netting laid above (optional)
interior Hoops, temp or permanent (optional)
Quality bales, Running bond, fiber oriented with arch to best distribute loads.
Exterior roofor furring hoops, Pvc or bamboo or 1x
Exterior purlins, 2x, shimmed as necessary
This whole assembly gets strapping, banding or twine.
Slip and then wash the exterior
Then Metal roofing, if horizontal profiled tip downwards to drain, or better unprofiled. Or add rafters.
Breathable metal roofed strawbale vault. With cattle panels, possibly 16′ dia…
The same panels make 3’x 7.5′ door form work.
Abe, want to ask you questions on insulating FC roofs. I’ll be shooting you an email soon.
This sounds like a good method. Tie the bales to the cattle panels as you go so they don’t move.
Any details on the build, photos of the build? I like the roof shape, something like that covered with a vapor barrier and acrylic cement could last forever.
How do they build the arch?
Contact the builders for details of their project.
People have been building similar straw bale vaults for around 15 years at the Lamas Foundation in NM, Mongolia, Colorado, California. There are various support systems such as wood trusses, poles, rebar, saplings and bamboo. I highly recommend metal roofing because the bales are vulnerable to water damage. Plaster always cracks eventually and the bales will rot if they get wet.
http://www.stuccosprayer.com/strawbale-cabin-in-two-weeks/
http://www.balewatch.com/vault.html
http://www.sandovalsignpost.com/jan08/html/time_off.html
http://www.greenberg-art.com/.Infographics/qq1sgStrawbale.jpg
Here’s a new for me: straw bale vaults in Austria… very nice! http://www.strawleonardo.eu/galleries/straw-bale-houses-examples-we-visited-or-presentetd-in-europe/
http://straw-bale-vaults-wangelin.blogspot.com/2011/09/2-seminarwoche.html
What about condensation under a metal roof? I would think a good vapor barrier with a stable cap would be less likely of a humidity issue than metal open to the air.
The vault is plastered so it’s unaffected by condensation. There’s is much less risk of leaks from condensation from metal roofs than snow and rain sitting directly on the roof. Expansion/contraction of ice is brutal on exposed plaster like this or on domes.