Super insulation, truss wall, double wall, etc.

[phalynx]

I just picked up a book on super insulated home design.  Was funny when I opened it up and saw John's name as an author.  Anyway, there were drawings and such about adding a truss wall to a regular built wall for extra insulation capacity.  I don't see this anywhere in any pictures or construction. 

What are the problems with truss walls?  Are they outdated?  I am working on a new design for a new place in a much colder climate and I really want to super insulate.  I saw the house that is being built in Moab using double wall construction and I am really interested in this. 

Which technique is the best for extra thick walls?  I don't want to spend tons of money on a "money is no object" design, but I would like get all the R factor I can get.

Let's discuss.

[Don_P]

I've not done one but just to bump this up, google larsen truss, I believe this is the wall truss you are thinking of.

[psammy]

Superinsulation is more than just walls.  Dealing with thermal breaks in the construction and insulating the foundation and roof are just as important (as well as high quality windows and doors).  For walls, building a double stud wall filled with cellulose will probably get you the biggest bang for your buck....if properly planned for in advance.  Fine Homebuilding magazine has had a couple good articles on high insulation and passive houses in the last year.  Good illustrations on how to achieve a high-performing home.  Don't forget proper moisture control and ventilation either...

good luck,
psammy

[John Raabe]

Phalynx:

The Larson truss was tried in a few super-insulated houses in Canada and the more severe climates of the US. It does provide for high wall insulation but has not generally been cost effective in new construction compared to other options such as double-wall or high-density batt in a single wall with a layer of foam insulation.