Foil Bubble Insulation Under Metal Roof

The r value of foil faced bubble wrap is so low that it has few if any advantages over rigid foam.

Foil bubble insulation under metal roof.

Green building advisor recently wrote an article about foil faced bubble wrap and did a balanced job of it. A secondary method of installation instead of installing under the attic rafters is to lay the foil insulation over the attic floor. Most brands of foil faced bubble wrap are only 3 8 inch thick or less and have an r value of only 1 0 or 1 1. It s important to know that ecofoil bubble insulation can absolutely be used in conjuction with other forms of traditional insulation for a combination to work against all 3 types of heat transfer.

The main one in the latter category is foil faced bubble wrap sold as insulation. Achieved by attaching to the underside of 2 x 4 roof purlins creating a 2 enclosed air space between bubble insulation and metal exterior roof. Foil insulation is a radiant barrier and it works by. Since the product often costs more per square foot than 1 inch thick rigid foam rated at r 5 why would anyone use bubble wrap as insulation.

There is no contained air gap inside the foil and the air gap outside the foil is fairly leaky i don t think that there will be much benefit from the insulation value of the bubble wrap. Unroll the foil bubble wrap insulation over the metal joists or purloins that create the frame for the roof. The question to ask yourself is do i want a foil interior or a white interior ecofoil double bubble white insulation is primarily used in pole barns metal buildings basement walls crawl spaces and storage units. Looking at the table of insulation values bubble wrap and foil will have limited benefit on reducing heat loss.

This insulation performs exactly the same as ecofoil double bubble foil insulation the white is just a cosmetic difference. This is why we recommend ecofoil bubble insulation for most metal building applications.