I have been reading all i can here, and talked to some great people here and learned alot, but have alot more to learn. Ive looked at SIPS, ive looked at ICF's. I live in Northern Maine where it seems we have winter for about 8 months a year. Im building in the spring, and OSB SIPS worry me longterm with moisture. ICF's I dont think are a great alternative in this cold weather. I read alot that the other wall systems, like dual walls, etc are too expensive. What are you thoughts on the overall best way to SUPERINSULATE my home to around R50+ in the walls, and R80+ in the ceilings. Airtight and superinsulation is my goal. I want to be able to heat this home in the winter with a candle :) 1500sq foot ranch, south facing.

Go to buiditsolar.com, under solar analysis find the insulation calculation section and play with different R-values to see what upgrading the insulation saves.

Went to builditsolar.com what a great site that is...

Anyhow, was reading up on the larsen truss system, this sounds like a great superinsulation system. The only thing thats unnerving to me is no outside sheathing. I couldnt do it without sheathing the house...

A good read here about different wall systems..

http://www.coldhamandhartman.com/upload/documents/BE07-WallSystemOptions.pdf

Here is a link to the online version of Solar Today magazine. solartoday-digital.org/solartoday/20081112 There is some good info in it. Look at the zero energy home on page 26. Looks like they used a double walled system. Also info on solar water heating systems on page 42.

John,
   Thanks for posting that link! As a proponent of Super Insulating, it's always good to see what others are doing to accomplish the feat.

Hi cwarman,

It would be great to be able to heat a 1500sf home with a candle, but it would have to be quite large!
I understand what you are looking for as a person from out of the cold country myself.

The old conventional way SIP's are manufacture with OSB can cause problems when exposed to moisture. The hybrid SIPs use steel studs and EPS (expanded polystyrene) allows you to avoid those problems. The EPS is the best insulation material that is non-toxic and non-allergenic with no toxic chemicals and is an excellent air barrier along with a complete thermo brake when using it with steel studs. When building, using this type of panel for your exterior walls, roof and sub-floor you will have a very thermo, airtight, healthy envelope. Also with these panels you do not need heavy equipment as with conventional SIPs to set them. Standard panels weight between 1.3 to 1.5 lbs/sq ft and are structural. Take a look!

David (kwikbuildpanels.com)

I don't know where you read that a double stud wall is prohibitively expensive. In fact I'm not exactly sure how you are going to get to R-50 in the walls without using something similar. A larsen truss is essentially a double stud wall, without exterior sheathing. If you want a very cost effective way to insulate to very high values, first frame the exterior wall normally with 2*4, 24" OC , sheathed. Then, come in about 8" on the inside and frame a 2*2 24" OC Wall. Now you have a 14" cavity to fill with whatever you want, dry cellulose, wet cellulose, fiberglass, Board Foam, Expanding Foam, ect. You can also run all your wires and plumbing in the gap between, with no need to drill any holes. You can hang drywall from the interior 2*2 wall. Also, you can use the Zip system green board for your exterior sheathing, tape the joints to get a vapor retarder. This keeps the wind out, but lets the moisture exit the wall. It will increase labor on your walls by about double, and the cost of materials by about 50%, but it will probably still be cheaper than sips.

Wow, SIPS must cost a lot where you live!

You will not be happy with 2x2 walls 24" oc, and with all this effort for super insulating why would you stick plumbing in an exterior wall and stuff the cavity full of wires?

Well, around here you would have to get them trucked in from pretty far. I guess depending on your proximity to a factory or distributor could change a lot. However, an interior 2*2 wall is insanely cheap to build. You could actually buy 2*6 studs and rip them into 2*4's with a 2*2 left over. Doing it that way, it takes no more material to build than a standard construction 2*6 wall, and just a little bit more labor. The carpentry crew I work for can build something like this in no time.

I have never seen a problem with a 2*2 wall for just holding up drywall. Once you nailed it in place at the top and bottom, it makes a very strong surface, especially for just holding up drywall. In a perfect world, you would never have to run plumbing in an exterior wall, however sometimes to get a layout you want, you have to run a pipe or two on the outside. The national electric code requires an outlet about every 6 feet, so unless all your rooms bordering your exterior walls are less than 6' in width, you are going to have wires. Also, I have never seen a house that made you walk to an interior wall to turn the lights on after you walk into the front door. There are going to be wires on the outside. What we do is cut little pieces of R-Max and fit it behind the electric boxes and pipes so that you don't have the reduced R value in those locations. I would be more worried about thermal bridging across your studs than I would a couple wires.

cwarman, I ran some numbers for you and here is what I got.
Assuming 15% OVE stack framing for all walls, Wood=R-1/inch, Expanding Foam=R-4/inch, Fiberglass/cellulose=R 3.5/inch, Dow Board= R 3.3.inch, R-max=R 6.7/inch

SIP- 2*6 Foam with 2" Dow exterior Foam Board= R 21.8

Double Stud- 2*4 Fiberglass, 4" R-Max, 2*4 Fiberglass=R 44.58

Modified Double Stud- 2*4, 8" gap, 2*2, whole assembly full of cellulose(wet or dry)= R 41.0

As an architect (google swinburne architect) I have done a number of superinsulated double stud wall houses here in Vermont with different builders. Each builder has brought some new insight which I can then incorporate into the next project. There are a number of small cost advantages that can add up to making it cheaper and even easier to build with double stud walls than traditional single stud walls plus the additional energy savings once you move in. I have also worked with SIPs and they can be a great product too. A bit more embodied energy though. Careful detailing (read: simple) can keep them cost effective.

2x2 doesnt make for a strong surface at all and its prone to splitting when you build it, you can rattle a 2x4 7/16 wall with a push of your hand, you could physically deflect a 2x2 wall with gypsum on it and could easily crack a seam.
Also with so much thought going into superinsulation why not design the layout you want with the plumbing out of the exterior wall, thats just common sense. As for the electric, your inspector and the nec wouldnt let you walk to an interior wall to turn the lights off, but you make it sound like the gap between the walls is a raceway for your panel, which again would be counter productive to the goal you're trying to attain.