Recently I received a sample of 1/4-
inch-thick foil-faced bubble pack
insulation material (FFBP). The
accompanying brochure claims that
a floor with the material stapled to
the bottom joist surface will have
an R-value of R-14.7. Another section
claims R-7.8 for the material
added to a basement wall between
two layers of furring strips. Beneath
both claims is a qualifying statement
which explains that the insulation
has demonstrated R-values of
R-8.3 for heat flow up, R-14.3 for
heat flow down, and R-9.8 for heat
flow horizontal under standard conditions
for the ASTM C-236 test
for R-values in a 6-inch cavity.
Can 1/4-inch-thick shiny bubble
pack create R-14.7 in a floor? Or R-
7.8 on a basement wall? And what
is the