I'm in the insulation phase of my icebox conversion to reefer and freezer.
Achieving a meaningful R value, while still retaining any interior space (a
prior 19cf icebox is laid out to become a 6cf reefer and 2.6cf freezer by
adding 2" and 4" to the 2" of expanded polystyrene already there), is
proving more challenging than I thought.

Glacier bay has a derisive comparison of their panels against the other VIP
available through resellers. While Glacier Bay has what seems to be a
clearly superior product, it also has a clearly superior price - one which
makes the reefer the single most expensive refit I'd consider at this time
(and there are many!), so unless I get radically more motivated, I'm
unlikely to do that.

It appears that the quality control is irregular on the other VIP, as the R
values look to be all over the map from sample to sample. (That's from
looking at their published comparisons.)

Having despaired of finding a high R value cut-to-depth block foam, and
talking with Dow about their products, their change in blowing agents about
a year ago makes it very unlikely I'd find any R8 (the prior Tuff-R rating)
product available. The current R6.5 is certainly better than nothing, but
I'd still like better.

I believe I understand one of the challenges with VIP is future air
intrusion, sort of inevitable, if I understand the process correctly.
However, I think I understand that protecting that panel is also crucial.

Would you recommend a VIP sandwiched between some layers of foam, with
edge-protect foam around the perimeter of each (all encased in 6mil plastic
and sealed, of course) as an effective means of radically increasing the R
on a 2 or 4 inch layer?

Or, given the apparent discrepancies in R from sample to sample, simply a
crap shoot?

Thanks.

L8R

Skip

--
Morgan 461 #2
SV Flying Pig
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