I'm always on the lookout for ways to make my house more energy-efficient. I'm also always buying things online and having them shipped to my house. This leads to a problem - a bevy of boxes, and a plethora of packing peanuts. Boxes can be broken down, folded up, and recycled. What to do about the packing peanuts? Could I kill two birds with one stone, and use them as fill to insulate my attic? The answer is probably not. I trolled around the web looking for someone esle with the same crazy idea and came up relatively short handed. One point I picked up pretty quickly is that they are not really Styrofoam packing peanuts, the are Polystyrene foam. Styrofoam is a trademark that refers to a specific product, and were talking about the wild multicolored mass of packing material I have at my disposal. One blogger confessed he has always had an urge to eat them. I'm not sure how that helps me, but there it is. In an article saying they can be broken down into biodegradable materials, one of the people commenting on his post wondered the same thing I did, but there were no answers. At Ask a Scientist, a web site of the U.S. Department of Energy, a kindred spirit asked about the R-value of packing peanuts and styrofoam, and here I got my most definitive answer:
As a professional civil engineer, I recommend against using packing foam for building purposes in the strongest possible way. This is a DANGEROUS idea. Foam panels sold for insulating buildings are treated with flame retardants while it is likely that foam peanuts are not. Untreated Polystyrene foam is dangerously flammable and produces highly toxic fumes.So there you have it. I still say "probably not," because the main problem is flammability and it's possible there's an inexpensive flame retardant that could be used. But just dumping them into cheap garbage bags and laying them in the rafters looks like a bad idea. Still, it's not like using polystyrene is unheard of in the building industry. For example, I have found instructions for using peanuts in green roof construction, usually bagged into batts or pillows. Thermasave building panels are made of polystyrene foam sandwiched between two (presumably flame-retardant) concrete boards. At least one interior designer (so, not quite a civil engineer) recommends using the peanuts to insulate basement windows. Many do-it-yourselfers recycle them into projects such as solar water heaters. Of course, those biodegradable packing peanuts made from corn starch are fairly common these days. If I ever have to buy any peanuts, I'll definitely get those, and still save the world on packing peanut at a time. But right now I still have a ton of non-degradable peanuts to deal with. There's a company in England turning them into pencils, rulers, and other school supplies, but they are too far away. I've only found a few other reuse ideas. So my best bets are to keep them around in case I have to do a lot of shipping (though now I'm worried about the fire hazard), or take them to a shipping company like Mailboxes, Etc (now the UPS Store) so that other people can reuse them. I'm not likely to be sending a lot of materials that require packing peanuts for shipping any time soon, so I guess I'll go with the latter. Maybe I'll help someone avoid getting fired.