Foil Insulation for Exterior Walls & Fiberglass | InfraStop®
If you want to combine insulation types, using reflective insulation and fiberglass insulation in a wall space can boost the R-value by 3.9 points. By utilizing reflective insulation, an R-21 total wall assembly can be created, with a vapor and moisture barrier.
In our InfraStop® line is a foil staple tab insulation product offered in 16″, 24″, and 48″ widths. The staple tab option allows you to recess the insulation 3/4″ into the stud bay.
This necessary 3/4″ airspace is for the reflective insulation to operate optimally. This is also your goal while installing, to create continuous 3/4″ airspace between the insulation and the interior panel, most often drywall.

For fiberglass insulation, choose R-19 un-faced option. You do not need the kraft back as the reflective insulation provides the vapor and moisture barrier. The un-faced is also less expensive.
To install, un-roll and cut the fiberglass insulation to length. Compress into the stud walls. To install the reflective insulation, unroll and cut to length. From the top, staple every 2″, 3″ as you go down the stud, compressing the fiberglass insulation as you go. Click the image for our installation page for this application.
The benefits of adding reflective insulation are two-fold. One, you get an increased thermal benefit, R-21, a 10% increase. Secondly, you get the major benefit of a radiant barrier. The reflective insulation will block 96% of radiant heat. This will pay dividends in comfort and in your pocket during the heating and cooling seasons.
Leave a Reply