Insulating ceiling fixtures
Would you suggest the best way to insulate ceiling fixtures exposed to an unconditioned attic is to set an insulated box (rigid foam) over the fixture? Then seal the box to the drywall ceiling. Fixtures such as ceiling fans, recessed lights, and speakers.
Do you have any other suggestions to seal & insulate these fixtures?
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Replies
Mark,
Since recessed can lights are problematic in many ways -- they leak air, they're hot, and they take up room that should be filled with insulation, leaving thin insulation above them -- it's best to remove your can lights and throw them in the Dumpster. Then replace the can lights with surface-mounted fixtures.
However, if you can't be persuaded to get rid of them, you can either build an airtight foam box to cover them with, or you can use a polystyrene beer cooler, or you can buy a product like Tenmat covers.
Site-built boxes are usually made from rigid foam scraps sealed at the corners with housewrap tape or canned spray foam.
In all cases, the cover or box should be sealed to the top of the drywall.