I was wondering if the blown insulation in the attic is very flammable or is it made out of stuff that is alittle bit flame retardant?
Im asking because I see the hot and neutral wires that go to the fan running right through it. It is in a well insulated sheath but I was just wondering?
standerd white home wiring in the oval rubber sheath
Do you suppose that, somewhere along the way, it might have occurred to the folks who write building codes to prohibit the use of flammable materials as insulation?
Rock wool and fiberglass are non-flammable.
Treated cellulose (sometimes in the form of recycled newspaper) is also used as blown-in insulation. It's treated with a flame retardant.
If you're worried, scoop up a handful, take it outdoors, and try to light it on fire.
Unless the stuff you have is very old, it has been treated to be fame retardant. It is safer, fire wise, with it than without it.
As Doug suggested, take a hand full and try and light it - outside.
Fiberglass is somewhat flammable. The binders burn and give off fumes. Rock wool has no binders, and has a considerably higher melt point (overall heat resistance) to boot.
I wouldn't expect fiberglass to cause a raging inferno - a bit of smolder rather, but saying it's totally non-flammable isn't quite true.
As a bit of confirmation:
_Most_ building code disallows the burial of K&T (unsheathed but insulated single conductor wiring) in insulation. Fiberglass binder flammability (and old/untreated blown cellulose) is one of the reasons. [Some building code (California for example IIRC) permits K&T burial in insulation with an engineer sign-off.]
"Should be" treated with fire retardant. All stuff now has to be, some of the older stuff isn't.
Definately worth trying if you're not quite exactly sure what it is.
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