I'm collecting quotes for additional spray-in attic insulation. All of the quotes involve a count of the can lights and work to block the top of the cans in the attic space. There wasn't any talk of determining whether the lights were IC or non-IC. House was built in 1979; maybe 1/3 of the can were put in new when we moved in 5 years ago.
We've got a low level of loose-fill insulation in the attic now (below the joists throughout), though enough that most of the cans are swimming in it, including the ones that we had installed 5 years ago.
The only information I've been able to find is that IC-rated cans have a metallic, unpainted interior; non-ICs will be white (short of pulling model numbers).
Is this a definitive way to identify IC vs. non-IC? If so, I want to make sure the ICs are sealed before the insulation goes in. I understand that there's no sealing possible for non-ICs (is it correct that sufficiently large air-tight boxes can be built over and around them?). Either way, I'm probably lucky the house hasn't burned down yet