wrote:

CJT wrote:

wrote:

Paul B. Andersen wrote:


... foam isn't a very good barrier. You should have a reflective foil
in the floor to stop radiation.

Wrong. Foam is opaque., It's an excellent radiation barrier.
Glass is also a longwave IR (heat) barrier.


FWIW, this suggests it is NOT:

http://dspace.mit.edu/bitstream/1721...1/24882071.pdf


Interesting. I don't see anything there about glass,

Perhaps I was unclear. I was addressing the foam issue.

and it looks like
radiation blocking additives only increased the foam resistance by 6%
(page 3) or 5% (page 32.) An 80% cell wall IR transmittance is less
important with more tiny cells in series, altho that raises the cost
and conductance.

Nick

The conclusion is that foam is not opaque.

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