What Is an R-value?
R-value is a measurement of the thermal resistance of a material, likewindow glassor insulation.
Higher R-values indicate better insulating abilities.
The Spruce / Jason Donnelly
What Reflectix Insulation Is
Reflectix is a brand of double-reflective insulation.
There is no metal content; it is all plastic.
Reflectix is a little thicker than a quarter-inch (5/16-inch).
It’s very lightweight (about 1-1/4 pounds per square foot).
It’s flexible enough to bend back on itself.
Reflectix is not a competitor tofiberglass.
It’s a different kind of insulation for different applications.
Reflectix caninsulate tight spaceswhere you cannot put thick insulation or where other types of insulation are not appropriate.
One airspace must be between Reflectix and the masonry wall and another space between the drywall and the Reflectix.
If you do not provide air space, Reflectix has less insulating value.
When Should You Buy Reflectix?
Even if you managed to do this, the R-value of this system would hover around R-3.9.
It makes no sense to use Reflectix where other products that are easier to install provide better insulating properties.
Reflectix Installation
Reflectix makes various products in different lengths and widths for many types of projects.
The product is usually stapled in place unless otherwise advised.
For instance, installing fiberglass is much easier than installing Reflectix.
But take into consideration that Reflectix is not good for large, expansive spaces in your home.
It may not always wrap easily around some pipes, vents, and certain water heaters.
In addition, Reflectix can be a little bit pricier than other types of insulation.
For example, a 50-foot roll of Reflectix that covers 200 square feet costs around $120.
Five rolls of R-13 fiberglass insulation also covering 200 square feet cost $150.
U.S. Department of Energy.