Can You Use Packing Peanuts As Insulation

Foam packing peanuts as insulation.

Can you use packing peanuts as insulation.

Osborn a former associate editor replies. Styrofoam is designed from air bubbles that are trapped to prevent heat energy from escaping. I m not sure when they switched to the new kind but it wasn t more than five years ago or so. In a wall cavity they would offer little resistance to air movement so they would be of limited r value.

The very reason why plastic peanuts work well as packing makes them a bad choice for wall insulation. By preventing heat loss packing peanuts make lovely insulators. Yes packing peanuts are excellent insulators because they are made out of styrofoam. The r value of polystyrene is about 4 0 per inch.

Plastic peanuts hold air that helps cushion whatever is being shipped. If the packing peanuts are newer they won t work. As far as being a fire hazard eps from which the peanuts are made can be and has been legally used in sheets for insulation as long as it s covered by a fire rated barrier such as drywall as bsee cm suggests above i would expect that if you were using peanuts in a wallspace that you would want to compress them as much as possible to maximise the extent to which they entrap air. New packing peanuts are made from a type of corn starch.

In the course of some framing it seems that there are spaces which get closed off and won t get insulated unless the gc does it on his own nickel during the framing process.