[GBlist] insulation

[Alan Courtright <acourtri@krl.org>]

Last week we went to talk to the people at Timbercraft, who build timber 
frames that are then usually put together with SIPs for nice 
high-efficiency homes.  They told us that their structures usually run 
15-20% more $$ than stickbuilt--right at the edge of acceptability as far 
as we're concerned.

One of the Timbercraft people then took us to a house that's being built 
not too far away, thinking that it was going to be a SIP-built house.  It 
wasn't: the contractor for the people who had the Timbercraft frame built 
told them he could do it cheaper by a) using "nailbase" for the roof and 
b) foam-in-place insulation instead of SIPs for the walls.

The nailbase is essentially a SIP with just one OSB side; the other has 
building paper on it.  The builder was applying it over 2x6 T&G with 
special screws; we were told that foam would be applied to all seams to 
seal 'em.

I'd read some time ago about foam-in-place insulation, but hadn't heard or 
read a thing about it for quite awhile.  Anyone here have any experience 
with it?  Is it better (subjectively or objectively) than SIPs or 
fiberglas bats?  Does it have the same 
humidity-infiltrates-the-closed-cells characteristics as the foam in SIPs?

I read recently about a new way of making aerogels so that they're tough 
rather than brittle; the brief description indicated it'd be valuable for 
insulation, but gave no hint of a timetable.  Anyone have more info?

Still searching for the "best" way to create a low-heat-loss house. . . .

                         -|//*Alan Courtright*\\|=   
                                Poulsbo, WA
                             acourtri@krl.org
                       



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