Can used plastic grocery bags be used for home insulation??

Question

My local landfill is pleading with the town to stop using them as they just blow away. I know that everyone has like 2000 of them stuffed under the kitchen sink, and get more every week. I know that before we started using reusable grocery sacks that we brought home 5-10 per week, and saved them thinking that we would use them as garbage bags. Yeah right, I bring home 10 for everyone that I fill with trash, and I know its bad to just throw them away. Anyway I build houses, and I know it would take a ton of bags to insulate a new house, but would they be effective anyway?

Answer 1

hey good idea! earthship stylee. maybe stuffed with newspaper and stacked up in the cavity? might be a bit slow, maybe you could get some child labour.

Answer 2

The short answer is, yes, they can be used for insulation.

As for being effective, I am not sure.  The 'R' value assigned to standard isulation is based on the amount of heat transfer that can pass through it and that is based on the amount of air that the material can capture, among other things.  If you could seal the bags so that a little bit of air was trapped in them or arrange them so that they did not completely flatten out, then they would give you some heat insulation.

The only drawback to this is that most of these bags are flamable, and would act as fuel if you ever had a house fire.

Answer 3

That's interesting!  When my husband and I took out the interior of our old (1920's) house we found they had insulated with newspaper.  The only problem I can see is it could be a fire hazard.  Plastic bags burn quickly, spread fire quickly and release poisonous chemicals while they burn.  I don't think they'd pass a building code.