We are selecting materials for a 1200 sq ft 1.5 story superinsulated / solar cabin on an off grid island on Howe Sound, North of Vancouver, B.C. 

There are no roads and the site is about 30 feet above the water on a rocky bluff.  We would need a crane with about a 100 foot reach to erect SIP panels onto the foundation (and a crane would be $200/hr plus $150/hr for barge and tug ......)

We wanted to do a post and beam frame with SIP skin to get R40.  In addition to the weight problem with big SIP panels we are worried about OSB in our wet coastal climate.  The only SIP manufacturer around here, Insulspan, only makes OSB skinned SIPs.  Wind driven water seems to make it's way in everywhere during the big storms.
 
Our innovative contractor suggested laminating SIPs at site with marine plywood and polyurethane foam to make hand manageable 4'x8' wall panels to skin the timber frame, covering these with a rain screen system and then use vertical board and batten siding to make a tight skin.

For the roof they suggest putting down a ceiling of T+G 2x6 plank over the post and beam frame and then gluing foam panels onto that, with plywood upper skin and then strapping under the metal roof.

Any ideas on how these onsite fabricated panels might work or any problems with these ideas?

- Graham



PS  I used to build passive solar houses and now want one myself!   The plan includes: Thermomax vacuum tube collectors mounted below the site, insulated glycol lines to a heat exchanger in a stratified heat store tank under the house, solar panel powered circulation pumps circulating glycol into something like a warmboard radiant floor system.   Even if it does not supply 100% heating it should be enough to keep the place from getting damp inside like most island cabins.

Try Extreme Panel Tech. ( www.extremepanel.com ) they will laminate plywood panels in 4x8. They have done several projects in Alaska and may have some idea's for you. If you are worried about the rainy season when you are building, you may have a problem with pressing your own panels on sight. Are you going to get a good press time and pressure to make these on site panels strong enough to become structual?

Chris

Thanks for the tip - I'll give them a call. You are right - we would be better off to get the smaller panels made up off site (vacuum pressed inside somewhere?) and then manhandle them into place up on the island.

Likely we are not going to be able to create structural panels by laminating our own so we would be relying on the post and beam structure.

Instead of panels we might be better off with a hybrid wall structure like the staggered stud Super Wall - double framed with fiberglass on the inner layer and foam on the outer layer like the one talked about in the thread

MAKING YOUR OWN INSULATION PANELS - Post by Panel Crafters - Looks like a good option for remote hard to access sites.

Ever since building a dock on our own my wife has decided that we are _not_building our own house! Maybe it's her memories of running bundles of 40 foot rebar over to the island on top of a string of aluminum skiffs

Steel SIPs are done all the time with no crane, no splines

Try these: http://www.techbuilt.com/

You can put whatever skin you want on these panels because they are structural without any skins.

Thanks - Steel Panels next to the ocean and salt spray - Hmmm. Maybe if they were galvanized like steel roofing.

Graham;

Most steel panels are G-90 galvanized coil, in our panels we use white galvalume steel skin, which is a better alloy than the G-90.
It is what most better steel roofs are made of and commonly used in a salt water environment

Thanks Chris - We have had a galvalume enamelled roof next to the sea for years with no problems - quite impressive.

graham