Dear Kevin,

I am sure this is going to be a hot topic very soon.

In Australia, the ASHRAE & other values have been used for some years with
regard to cavity insulation values. This includes subfloors, walls, roof
spaces and spaces between roofing and sarking. We have conducted a few
preliminary studies with Engineering honours and Architecture PhD students
on actual buildings. They have all shown dramatically different results to
what was previously accepted. In the case of walls this has a dramatic
affect on the current practice of placing the insulation on the outside of
the cavity.

In terms of the roof model we have documented variations up to 20 deg C
between DSP and observed results. Subfloors having variations but to a
lessor magnitude.

We are hoping for some future moneys to go back to the fundamentals of the
physics models and modify them to relate to what is really occurring in
buildings. We have measured amazing horizontal and vertical air currents in
cavity spaces dependent on wall orientation.

Mark Dewsbury