Support for Larsen truss for a superinsulated house
A Larsen truss is a structure that supports insulation on the outside of the framing of a house.
A Larsen truss can be built very lightly, because it supports only
itself and the insulation. Fig. 1 shows one way of supporting a
Larsen truss on a conventionally framed house. A piece of cantilevered plywood serves as both floor and support for the truss.
Manufactured Larsen trusses are not widely available. This construction
method might simplify details of site-built Larsen trusses, especially at corners.
Fig. 1 shows the configuration of the support at the sides of the house perpendicular to the joists. Fig. 2 shows the configuration of the support at the sides of the house parallel to the joists.
For a more conventional Larsen truss arrangment see Fig.3 , reproduced
from The Superinsulated Home Book, by J.D. Ned Nisson, and Guatam Dutt,
illustrated by Michael Web, 1985, John Wiley & Sons.
A nice example of a house built with Larsen trusses may be seen at http://www.greenfret.com/house/larsen.html
David Delaney's site