Steven, that is a very good question and a complicated one. I've written threads on how walls or the total envelope(roof, foundation, windows, doors, penetrations, etc) are active and passive HVAC mechanical units, or that is the way I see them. With that said they can add to HVAC loads or reduce them. More importantly they add health benefits or remove them.... allergies, cancer, etc.
So my design approach is to focus on the envelope first. I just can't seem to get past it after two years of looking at all the possibilities. I think I'm obsessed!
or perhaps challenged especially when we start looking at cost, code(safety requirements(structures fire and smoke etc), sub-divisions dos and don't allow), etc...). If your in rural with lots of DIY time or $$$$ where noone cares it is MUCH easier.
So back to walls. I got some studs, American Clay plaster samples (nice looking I'll post some cost soon). Learned quite a bit from there site today, so I'm going to try my beginner hand at plasters to their on-line instructions. Tomorrow I call and have some questions. I'll also call Carmeuse lime about there type O interior mix, and perhaps my friend Bill Bradbury if he's still alive I have not seen out here in a while. He does
alot of lime on drywall renovations and has a lime co in Idaho he recommends. That is the other way I design is before I spec it out on a drawing I build it or mock it up, talk to trades with
experience. Then I can get a feel for the trades I'll assign to the task. As in clay or lime plaster veneer that can be our plaster/stucco or paint and drywall trades so I can get competitive quotes. If I go all thick lime plaster that is one quote, plaster trade.
I already know the insulation will be mineral wool unless someone know what can beat it, but I'd that differently. As soon as I have my stud and truss cost I'll compare it to Timber bolts(wall and truss timbers combined, see my blog below we did on a commercial job) craned in and if it looks good I'll model it.
Cost, durability, toxicity, sustainability,
Cost is huge, toxicity is hard to place value on in light of all the false green washing out there the average(non-educated) person may not buy it. "natural" might work, maybe, perhaps to some people that go to health food stores like me or chemicall sensitive, small groups not the masses
. Sustainability is a new buzz word and a hard
sell in America where the average person buys another home or moves every five years. I think getting them to pay more is going to take a very convincing sales staff we do have, but still in reality a hard sell but I do like the word. Nice!
The exterior is tricky since most subdivisions mandate a certain look, color, for siding and roof materials such as asphalt shingles, so some of that is out of my control and unfortunately in the hands of the developer or ACC or common
land owners by land contract and law. The best plan I have is 1-direct meaning I will use a structural rated siding like LP or plywood, it has to be stamped by APA or an approved agency in code with an on center spacing to satisfy braced wall code (shear, racking). The OSB is the pic above is gone which I call and improvement. I back yard tested the "fiberboard" LP "smartside panel siding and it held up well in
water submersion, I just do like the fact I can delam it with my finger nail at the T&G. Georgia Pacific plywood structural siding I cannot do that. We'll get into more of that later since it also mates directly to mineral wool so we have to be careful. I may put a furring strip rain drain gap there if cost allows. Roxul and Thermafiber spec out house wrap. That is OK since in my mind the interior materials are more important. Probably T&G pine or cedar ceiling, again cost?
I'm just about to try
chicken wire as lath, wood is too expensive. I'm also thinking about getting some marbled sand, different clay types and experimenting to drop cost and keep it local.
But yes, it is easy to through ideas out there. This thread is different I hope it looks at reality cost and safety. BTW: If you have an idea don't be shy, I know
enough about code and ACCs to identify it's feasibility.
Thanks for the interest, I was not going to not waste my time if there is none. I have alot to do. Behind all this I have a 3,200 SF flex/next generation spec home to get past the dang envelope once and for all. After which I'll run the HVAC loads through some software it
should be low, decide the HVAC unit and rest of building design for improvements, cost reductions. So what I will have done is move cost from HVAC to the envelope and provide a more comfortable living environment....not easy!
BTW: By following code we do not have the expense of a PE. Single family US homes for the most part up to a duplex and three stories do not require the stamp of Architect. The software I am using is complex and has a steep learning curve, one can do their own models and drawing's but it takes time to gain the skills.