Replies

1. 
   Riversong | May 08, 2010 03:04pm | #1

   The Larsen Truss system, originally developed by John Larsen of Alberta CAN in the 70's for retrofit applications, has been used and modified by intrepid designers and builders ever since. I'm one of those who have successfully designed and built superinsulated, breatheable, non petrochemical homes with a modification of Larsen's approach for decades.

   It is still being used by responsible designers and builders in both its original exterior truss form as well as with such creative variations as using vertical I-Joists for studs. They are filled with blown insulation, occassionally JM Spider fiberglass but more often dense-pack cellulose (which is far more ecologically benign and healthy).

   This system creates some of the most efficient and livable homes without resort to plastic foams, rigid or sprayed, above grade.

2. 
   Riversong | May 08, 2010 05:34pm | #2

   My own iteration of the truss-wall system can be seen here: http://www.builditsolar.com/Projects/SolarHomes/LarsenTruss/LarsenTruss.htm

   I've also designed several other variations to this theme, using KD lumber and eliminating the repetitive gussets. One of those is about to be built as a lake cottage in Tinmouth VT by others, on a walk-out basement made of a trussed concrete system called ThermoMass.

3. 
   homedesign | May 08, 2010 07:52pm | #3

   Robert,
   I think I have said this before.
   It's kind of a shame that you have to cover your framing.
   It reminds me of the Architecture of Faye Jones.
   here is a link
   http://www.architectureweek.com/cgi-bin/awimage?dir=2004/0915&article=news_1-1.html&image=12511_image_3.jpg&return=index.html

4. 
   Riversong | May 08, 2010 07:59pm | #4

   I guess Fay wasn't designing for northern New England.

   But I do love the sight and smell and feel of the building skeleton before it gets covered. And it's at that point that I hang a hemlock sprig onto the ridge to honor the spirits of the tree people who have their lives so that others may live.

5. 
   Tex | May 09, 2010 01:05pm | #5

   As with most all non-conventional building systems, a truss wall system or the Larssen Truss System can be a good way to build a house, but it is not a fit for all. Make sure you are knowledgeable, prepared and qualified. Robert has been working with this product for many years and is easy for him, but make sure you are cover on the pros and cons.
   http://www.buildingscience.com/documents/information-sheets/high-r-value-wall-assemblies/high-r-wall-05-truss-wall-construction/
   https://www.greenbuildingadvisor.com/community/forum/green-building-techniques/16059/cost-effective-exterior-wall-construction
   http://www.greenfret.com/house/larsen.html

6. 
   Riversong | May 09, 2010 01:16pm | #6

   Tex,

   Trussed or double walls are not a "product" but an approach to building low-cost highly efficient homes. In fact, it is a far more conventional approach than most of the modern "green" systems such as thick exterior insulation or sprayed foam.

   While it does have a bit of a learning curve for the designer, it's based on simple framing techniques which any competent builder can manage. And while it's suitable to all architectural styles, it's more amenable to simple geometries, which are the most green configurations anyway.

7. 
   Brian | May 10, 2010 07:08pm | #7

   Thanks very much Robert. As you can tell I'm getting caught up on my homework-but I'm glad to know that others have been forging ahead.