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We have several modified straw bale buildings in San Diego County including one at the Wild Animal Park. In addition, there is one being built to house two Friends groups and the Peace Resource Center.

It's "modified" because the local governments don't trust straw bale as a good structural member. That means it's really post and beam.

In any event, the "truth window" is a feature usually added to a structure that will be used as a demonstration structure. If you want crunchy people touring your summer house, it might be possible to get some grant money to help build it. If you don't care about being a demonstration home -- and I pretty sure you don't -- then you don't "need" the truth window.

Also, we did look into packed earth floors for the Peace Resource Center, but decided against them in favor of pretty tile.

The lobby for straw bale touts the "environmentally friendly" aspects and adds all they can think of to make it all self suficient as part of the sell to building departments. Even then, it remains a fringe building technique that will likely not grow into anything substantial. People just think the whole thing is weird. :)

If I was a government inspector and had some knowledge of the more earthy-crunchy straw-bale builders, I'd be pretty suspicious of using them as a structural element too, not because straw is flimsy, but because of all the other earthy-crunchy things that come along with it :-)

What I'm looking at is a modified balloon frame (using 2x8 joists at bale-width (3 ft?) intervals, which gives a good window size, plus doesn't involve manipulating 4x4 or 6x6 beams -- an important consideration when the house is going to be built by two adults and their helpers) It would make the framing a little more expensive, but I'd make up for it by not having to purchase fiberglass insulation for anything other than the roof. It would most likely need some sort of inspection hatches on the inside, so I could occasionally stuff humidity probes into the bales at the base of the walls to check for condensation.

I think that if I was shopping for grants, I'd promise to set up a website with lots and lots of photos of the house under construction, and the obligatory scans of the bill of materials and heating bills, showing how much the insulation actually cost and how much I was suffering for it (I'm guessing that if I do use strawbale and get a good heat-storage fireplace, I could heat a cottage for basically nothing; when we were heating our big poorly insulated house with the furnace insert in our fireplace, got the downstairs up to about 72f by burning a a chopped up 8' x 18" diameter log over the course of two days. A well-insulated small house should be able to do better than that without any trouble), and then I'd do ecotouring for people who didn't want to be earthy-crunchier than thou, but wanted to reap the benefits of having a snug house built from recycled bits.

My dream is to dump this house, buy a lot in Vancouver BC, then move up there and build a snug little recycled-materials house in the city. There are a few obstacles I still need to deal with before doing that (and that's not including Canadian migrant visas, which are apparently a real pain to get even if you're upper middle class), but in any case I'm a boring old aesthetic conservative and I want my house to resemble the bungalows and prairie-style houses I grew up in and around. So no truth windows for me.

Straw is fine unless and until it gets wet; once it gets wet -- which is fair odds in Vancouver -- it's doomed, and unrecoverable. (This is basically a 'does the roof ever leak over the lifetime of the house?' question.)

The other thing to think about for building in Vancouver is that it's due a Richter 6.5+ earthquake sometime. Most of the recent large construction is designed with that in mind; much of the older construction is not. Anything you put up ought to be, and while frame structures certainly can be it's hard to do that with masonry walls, which straw bales -- even stacked betwixt 2x8s -- may approximate.

I'd be looking at pre-cast concrete, post-and-beam with tensioned plywood sandwich wall panels (should be able to recover the materials for that -- old I beam post and beam, recycled plywood, recycled 2x4, empty water bottle insulation...), or just a straight up modern quonset hut; those are relatively inexpensive and come in R-lots. Lets you do the interior with recycled materials, gets the shell up fast, and gives you something that -- properly fastened to the foundation -- will shrug the earthquake.

I'm not that worried about strawbales getting wet; Nebraska-style (structural) walls aren't even on the horizon, so the bales could be topped off by a nonpermiable header of one sort or another. And I'm very fond of craftsman/prairie-style wide eaves, which would tend to discourage all but a pretty enthusiastic gale (offer not valid if the gale pulls the roof off the building.)

Earthquake protection, well, yes, that's another thing. But what I'd do would be to put the structural sheathing on the inside of the walls instead of on the outside, like:

                 |== <----- 2x8 stud
     plywood --> |xxxxx
                 |xxxxx <-- strawbale
    room         |xxxxx
                 |xxxxx         outside
                 |xxxxx
                 |==

A lot of the references I've read about strawbale say that the less permiable membrane be on the inside, so that the humid air from the inside won't get into the strawbale, but if it does, it will vent through to the outside. So by merely flipping the structure of the house inside out, I can get the shear resistance of the panel wals and still get the cheap insulation (and lovely inset windows) from the straw. And since the strawbale isn't structural, a leak into one of the bale columns would most likely mean only having to replace that column (depending on what I used as fill to pad out from the 2x8 to the outside wall) of bales, instead of losing the entire wall.

Actually, now that you've put the worm into my head I've been looking at more strawbale house resources, and a common claim is that a nebraska-style frame is actually more earthquake-resistant than a plate girder frame. I'd have to look at some of the reference materials to believe this, but if it's so my suggestion of reverse wall girders might not be a good plan. The cheap and well-insulated parts of straw-bale construction are very appealing after going down US$900 (650 for heating oil plus 250 to have the stupid oil furnace fixed after it ate an air bubble and a oil clot) for heating costs before December was half over this year.

It would be sucky to have a stucco house (too much time spent in California has left me with a deep and abiding loathing for the shotcrete "stucco" that's found on too many houses and apartment buildings there), and I'm guessing that the shock absorbent qualities claimed for strawbale would mean that after The Big One hits Vancouver my house would be standing, but every bit of plaster inside the house would be cracked into teeny tiny pieces (and, of course, the nasty stucco would be heaped around the outside of the house like a really bad case of structural dandruff) but better insulation is kind of appealing and the hypothetical money I could save would be enough for me to slap a 4-6mw battery array onto the roof.

(I can hear the best muttering something about this plan. Something about "over my" something "body".)

Stucco in Vancouver develops mold, mildew, and moss. (As opposed to collapsing in leprous flakes, which is what it does when the Southern Ontario freeze/thaw cycle gets to it.)

You could just do the outside with shotcrete over the straw, parge it roughly flat, and then stick aluminum siding or similar on it. If you stuck rebar -- well, reinforcing wire mesh -- into the gaps before you shotcreted it would even be quite strong.

The problem I was seeing with the inside-wall-skin version is how you stick the weather layer on the outside so that it's attached to the structural frame; stucco would certainly do that, but nothing porous is a good idea in Vancouver. (Victoria and Nanimo are even worse for that.)

Insulation, yeah, it's a good thing, but you don't have to use straw. Even if the mice aren't going to appreciate you as much for failing to provide an entire house made of nesting material.

Fireproof and non-porous more or less limits things to glass block and foamed glass block; there might be foamed metal insulation or sintered silicon carbide or something but those aren't even vaguely economical.

If you have to go for straw you might as well just do a wide sill on the foundation, regular interior balloon walls, the layer of straw bales, and a light -- 24" centres -- plywood sheathing wall over that, with aluminum siding to taste. :)

Well, I don't think you'll find any disagreement when you say that stucco is teh 3v1l. I'm not sure about mice infestation; when I looked, I found a couple of really spectacular horror stories (one which included a monster moth infestation, too!), but they're few and far between. I think that strawbale that's covered with plaster might be fairly inhospitable to mice, Republicans, and other scurrying vermin, and in any case if I strawbaled there'd be 4 feet between the first strawbale and the ground (2 feet of concrete footing, then a foot of floor, then a foot clearance so that pipes breaking won't soak the walls), so the happy nesting material might be too far out of the way for them.

If I trebled layers of fiberglass insulation (and if the R-values are additive), I could get R57 with 18 inches of insulation. It would be kind of expensive; I think that it would cost me about US$6000 for 18 inches all around as opposed to $2500 for strawbale + insulated floor and roof. But that would make it pretty easy to shingle or clapboard the sides of the house, while I'd have to do some sort of studding to get a proper exterior on the house.

But strawbale doesn't have fiberglass fragments in it, and those are really nasty little glassy bastards.