Good insulation works by trapping air.
Packing peanuts attic insulation.
We found millions of packing peanuts loose in the attic presumably intended to function as insulation.
New packing peanuts are made from a type of corn starch.
Another problem is that newer environmentally friendly cornstarch peanuts dissolve when wet.
The problem comes from the large interstitual spaces between the pieces.
The r value of polystyrene is about 4 0 per inch.
Osborn a former associate editor replies.
I m not sure when they switched to the new kind but it wasn t more than five years ago or so.
The older kind might work okay.
In a wall cavity they would offer little resistance to air movement so they would be of limited r value.
Air with very small temperature gradients will start to float through the peanut pack and transfer heat from the warm surface to colder zones with little resistance.
Plastic peanuts hold air that helps cushion whatever is being shipped.
The very reason why plastic peanuts work well as packing makes them a bad choice for wall insulation.
Has anyone ever seen this before.
If they get wet they ll dissolve and they re made to be highly biodegradable so they ll break down pretty quickly anyway.