Recessed lighting and ceiling fans are oft times difficult to deal with when floating a ceiling. You are correct in your assessment that sound can pass readily through these areas. The fan can be sealed with a good acoustical caulk, like the caulk you can get at Soundproofing.org.
Now the recessed lights are a different story as the light can will get very hot. Some of my customers have lined the outsides of these cans with the closed cell foam, and though this material is very flame retardant there still is a possibility of this material deforming under intense and constant heat.
Generally when floating a ceiling, I recommend the use of track lighting as opposed to the recessed can lights.
You have to make a choice when floating a ceiling, and that is to decide which is most important to you. Is it the asthetics of the ceiling, or the fact that it is a soundproof ceiling, If you are losing sleep because of noise, then it seems to me that recessed lighting should be a secondary consideration.
If any of our other posters have found a solution to this problem, please post your remedy for recessed lighting in a floated ceiling. I would be most interested in reading any solution to this delemma.
Jack, thank for the interesting post.
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