This is a short little video on how to install
radiant barrier into a wall assembly on basically, how to keep the heat out; this is more of
a hot weather or summer application. We get a lot of customers calling and they are doing
a remodel or tearing out some walls, they’ve got their studs open, they’ve got their exterior
sheathing and they want to know whether or not they can install a radiant barrier on
that west or south facing wall to help reduce the heat coming in. The answer is “yes” but
the first thing you have to do in order to do this is create an air space; you have to
have an air space for a radiant barrier to exist. Normally what happens if you stuff
this bay full of insulation is the exterior sheathing gets hot and the heat travels by
conduction all the way through the insulation and in to the house. When you create this
air space and you put the radiant barrier foil right there, what’s going to happen is
the exterior is going to get hot, it’s going to want to conduct across but when it hits
this air space, in order to get across that air space, it mostly has to convert to radiant
heat and once heat is in a radiant form, it’s great because we own it. We can just reflect
it back. What that does is keep the insulation right here cooler and that drives less heat
into the home. So, the insulation is more effective basically; it’s almost like adding
more insulation is the net effect. Now if you are doing a remodel and you really want
to do it: what you do is you put some foam strips in, then you’re going to staple your
foil up – so the foil is going to go basically right up against the wall on the spacers (use
either 1/2″ or 3/4″ foam board) staple and pull it across and staple on the other side.
Put your batt insulation in and then this is an optional layer. This is 1/2″ blue board
(or foam board – blue, pink, it doesn’t really matter) and what it does is it gives more
R-value to the wall but it also makes the wall air tight and it reduces what is called
“thermal bypass.” Basically this is heat coming through the stud that would go into the house.
It’s kind of like putting a jacket on that wall, and ultimately drywall or sheetrock.
So, coming from the outside in, you have: exterior sheathing, you’ve got your air space
made up by your foam furring strips then foil, you’ve got your insulation, optional foam
board, and then sheetrock. Now if you do the foam board and the sheetrock, one thing you
might want to do is offset all the pieces so you don’t have two seams on one location;
you don’t want to have a foam seam right on top of a sheetrock seam. Really, that is about
it! It’s an easy install, it’s cheap, it works great; you’re going to notice this wall is
a lot cooler, a lot less heat is coming through, the room is going to be a lot more comfortable
and energy efficient. For more information, visit www.AtticFoil.com or www.WareHouseFoil.com.