I think that if you want something out of the mainstream, you'll either have to shop around for a competent builder willing to do this (will be expensive) or DIY.

We also tried to go green as much as possible. When we looked into geothermal the HAVC rep said our location wasn't compatible to an efficient system. We did use the SIP systems for our outside walls and roof. This worked out nicely for us since we are DIY and having the panels allowed us to put in our windows and exterior doors at our snails pace. The only problem we had was the electrical wiring. Even though the panels come with the channels for the wiring, they weren't always where you needed them so we had to make our own channels through the foam. Not so easy.
So glad some of us are trying to do our part in greening the world. If only we could convince contractors that they should do the same....

I love building energy efficient homes!

But my next spec home will be strictly to minimum Code as no buyers around here have shown the slightest willingness to pay more for what they can't see or touch.

Before you cast everything in stone, you may want to look at some of the video here. (Especially the building envelope stuff.)

Couple other thoughts....

Search this site and others for "thermal bridging".
If you're considering any upstairs spaces in the future, make sure the floor joists are 2x10.
High density foam isn't the be-all end-all of all forms of insulation. It's just one other form that suits some applications better than others.

Here is a link that might be useful: Gardenweb thread about videos

egouin... After reading the comments at your website, a couple of thigs pop out.
1) Open-cell foam (like Sealection500) is very competitive and has a huge advantage to closed cell in one big area - it will allow water to pass. If you ever have a leak, then you will thank your lucky stars that you found it when it started! Rather than weeks or months later when the water finally found an egress point and you have more damage and mold that you care for. We had a roof leak six months into our occupancy and if it wasn't for the open cell, we still may not know it was there.

2) Your idea to seal (portions of) the attic floor with foam and then do blown in cellulose on top of it is exactly what we did on the attic space above our master suite. It worked out very well.

(BTW, we built ICF.)

good luck first...
and little rain on your party and no offence ,but sip/modular hybrids(very energy efficient) are built in Europe and Japan for past 20-30 years..... and i think in Ca there is a company who are building/designing sip/modular hybrids since 2001.

It's nice to see folks taking the inatitive to incorporate green building practices which can be done w/o getting caught up in the "go green" web of rip offs that are cropping up. Personal research and collaborating with a builder are key if you can find an open minded builder, but the point is, take the responsibility opon yourself and it can get results. As worthy states, most folks are only interested in cosmetics such as the current trend of granite/stainless steel/ and paint colors with names that only funk & wagnalls can appreciate, but anything you can do is key. Homes are far more energy efficient than ever and even doing things like recycling materials(cardboards, plastics, cooper cut-offs,etc), helps.

Actually, more rain... Sunlight Homes, in Albuquerque, have been doing it for many years. They have an excellent site -- one of the best I have ever seen -- detailing the whole process.

They do:
complete custom design
 SIP walls (R-35)+roof (R-43)
 wood crawlspace floor system
 Pella triple glazed windows
 Pella skylights + entry door
 insulated exterior doors
 framing lumber (interior walls, frame garage, porches)

Your builder erects, and adds the final inside finish-out, with Sunlight supplying the builder with the information they need to successfully build a SIP home. (Their son is also the website guru, and photographer for American Clay Earth Plaster who shot our home, and that's how I first found out about Sunlight.)

what is the shear stregh of SIP's? aka .. how strong is the bond between foam and osb. I've seen some where osb is routed out alot for wiring and wonder what kind of loss in strength that is

I agree with the OP that building green can be frustrating and expensive. We went with ICF (hope to move in during February) and decided against the geothermal as we felt it would be overkill with ICF. One nice point about geothermal is that in our area the prices have come down significantly. It is still more expensive than conventional but not nearly as pricy as five years ago. Radiant heat in my area is cost prohibitive as there are so few contractors that are skilled at installing. Further, one still must have A/C where we live and the cost to add the A/C venting on top of the super expensive radiant heat just did not work out with our budget.

Congratulations to the OP for sticking this out.

Teresa

I always enjoy threads dealing with energy-efficient homes, as our plan is to, within the next few years, build a home that is as energy-efficient as possible.

Like teresa b (above) originally considered, we have thought about an ICF home and geothermal.

The ICF concept is still almost unknown in our area. A few years ago, we attended a home show, and not only was ICF not represented, no one with whom we spoke knew what we were talking about.

Fortunately, I have located a builder in the area who has some experience with the Logix ICF system, so I hope to speak with him in the future.

Another interesting thing -- at a party last night, I spoke with a guy who has one of those Hardy (brand) woodburning furnaces, the type that is located outside the home, with underground lines connecting it to a heat exchanger located in the standard heating system. It also preheats water going into the water heater, to save on water heating costs. Something else I will consider!