Manufacturers of foil-faced bubble wrap are still convincing a significant number of homeowners to buy their worthless products out of the mistaken belief that bubble wrap is insulation. It isn’t.
Even worse, a few contractors—some of whom are ignorant, and others of whom are dishonest—substitute bubble wrap for insulation in a few critical locations where real insulation is needed: under concrete slabs, for example, or on the outside of metal ducts.
Back in 2014, I wrote a GBA article warning readers to “Stay Away from Foil-Faced Bubble Wrap.” My advice still applies to the current crop of worthless bubble-wrap products. Unfortunately, the decades-old bubble-wrap scam has not gone away.
Blurring the line between material R-values and assembly R-values
We’ll start by outlining the basic facts about foil-faced bubble wrap:
Bubble-wrap marketing materials often tout ridiculously high R-values that have nothing to do with the thermal performance of the material; the exaggerated numbers are based on assembly R-values, not material R-values. Assembly R-values take credit for the R-value of building component layers that aren’t sold by bubble wrap manufacturers: things like layers of plywood, drywall, or air spaces located between the bubble wrap and an adjacent surface.
If a manufacturer is claiming that its product is a type of insulation—and some bubble wrap manufacturers are doing exactly that—then the advertised R-value for the product must be the R-value of the product alone, not an assembly R-value that includes the R-value of plywood, drywall, or air spaces. This isn’t just my opinion; it’s a principle established in a federal law (16 CFR 460) called the R-value Rule. The R-value Rule applies to manufacturers, retailers, and builders. Exaggerating product R-values…