Straw Bale House construction

[themisfithitman]

I was looking online at school today during my free period and I found a site that was talking about all the benefits of building with straw bales. I thought it sounded like a good idea, but I was wondering what some of the cons of the whole idea might be, also, if later, I decide to build a straw bale house, what kind of money would it save me, and what impact would it have on the environment?

Thanks.

[Johnny Electriglide]

There is reportedly enough rice straw burned yearly in California to provide the exterior walls of all houses built in the USA. In other words, there is plenty of straw and it helps the environment to use it for superinsulation of homes. At R-43, and a compressive strength of 5,000 lbs. per bale, it certainly is sensible. Generally, it is used as infill where the compressive loads are greater--i.e. more than a 20' single story span. Books from Realgoods.com are helpful. Really, it can be used as a concrete panel system, and there are more and more engineers qualified to do the necessary calculations.
Generally, strawbales are not heavy and fairly easy to work with, but must be protected from weather and wind. The problems I've heard about were rainwater intrusion and rot, especially on two story models. The latest books address these problems. Done right, do it yourself, you may save up to 10% on construction and 75% on subsequent heating bills. You can save even more on utility costs with alternative energy systems, and solar gain/thermal mass trombe wall systems, or the more expensive geo-thermal heat exchanger systems.

[Corey]

Keeping it dry. moisture mold mildew would be nasty not to mention fire resistance especially with the heating environment. I could see the house hoing up in flames.

[Johnny Electriglide]

The concrete/stucco covered bale panel wall has a 3 hour fire rating, at least, just like the Rammed Earth tire stucco covered wall system. Even as a fill it is much better than wood frame. With the straw bale wall there are special foundation designs, bond beam designs, anti-uplift designs, allowance for compression and even a reinforced concrete 3" exterior for load bearing (with finish stucco cover), plaster over stucco interiors, special electrical embedding, and large over hangs. Easier than the rammed earth tire wall system which is also much stronger. Insulation factor 43 vs 30. I used course soil cement pour method with tire walls for safe stability and weatherproof-ness on the way up, whereas the bales need to be tarped and braced as they go up. Tires and subsoil (if good gravel) are free where straw bales cost, usually.

[dan]

bale house old and new after seeing a old (1800+) bale house i kept looking for info. they work. back in the 60's i had used borax as a bug and fire proffer on chopped newspaper insulant. so i was thinking about ways of doing more than adding it to the whatever bale. then people started really doing it, not thinking about it.. now bale house, and barns and churches started with coming of the hay baler. but not just hay. weeds that were too tuff for animal food were preferred. one farmer is said to have pulled his baler down his fence and picked up tumbleweeds. one of the new guys said that if the baler is set to pack the bale real heavy, they burn like phone books. that's to say not much. the old timers used river clay on the walls. with a big over hang to keep rain off. the walls. later they mixed asphalt in the top coat. the old ones were bad about bugs, like bed bugs. so they had to keep the inside plastered to hold out the bugs. with borax that would not matter. but it does not anyway they say. standard water proofing should keep out water just like it does on a wood house.

[mybarnconversion]

As others have mentioned ... similar to sheeps wool insulation, a major con is the amount of nasty chemicals that you may need to add to the material to keep it fire retardant and bug free. These will obviously varying depending on where you are in the world and whatever building regulations that are in force.

[Johnny Electriglide]

In the past 14 years I've never heard of a strawbale house using chemicals for bugs or fire retardation. I have heard of rot from water intrusion from too high walls with too little overhang, insufficient ground clearance of footings, and not enough water proofing. The designs are modern, fire and insect retardant without nasty chemicals except for the lime and portland cement in the stucco/concrete, and plaster parts before they set.
The strawbale/concrete panel wall is fireproof for at least three hours with 1.125" stucco plaster or more per side, and compressed enough so there are no channels for bugs and insufficient air to maintain combustion. Sheeps' wool for insulation is not ecologically or structurally sound enough to even have any plethora of books on it like straw (not hay) bale construction.

[Seeria]

Hello everyone

Strawbale building is something we've had an interest in for a few years and plan to use it to build our own housing in the near future.

Like with a lot of building and things "green" there is a lot of myths and misconceptions.

If you want experiences I'd suggest visiting the logs/blogs of people that have built with it and lived in it for a good length of time.

If you want studies you can start at places like:

The Ontario Straw Bale Building Coalition
Where they do research as does the Canadian MHC.

There is also the Last Straw which has articles of current and early days. T h e L a s t S t r a w - ( w w w . t h e l a s t s t r a w . o r g )


Kind regards

[johnaydan]

Yup,

Strawbale house is certainly very very interesting, thanks a tonne for sharing the info...

[natureguy]

After massive earthquake in Gujarat (India) in 2001 (or may be it was 2000) a few local NGO's joined hands to build houses of mud (single room sorts) which costs only INR 15000 including everything.

Best thing is that in summer the temp inside the huts are pretty low while in winter it feels much more warm.

Lets go back to stone age. What say?