Soundproofing ceiling in bsmnt apt

[Laura Johnson]

We we are trying to soundproof a basement apartment ceiling. We have torn down the previous drywall so that we have a clean slate. Our plans include searching for and filling small holes and cavities with acoustical caulk, adding a layer of roxul safe and sound between joist, attaching resilient channeling, and finishing with a 5/8 in drywall layer. 

I am also trying to find a product to slip inside the ductwork to the ceiling registers. I'm not sure how else to help prevent sound transfer because the basement and upstairs share the main ducting. 

I have been reading about isolation clips, I can't decide if they are worth the price or not. I'm finding them at about 5 bucks per clip. The apartment is approximately 700 square feet of ceiling oh, that's not including closets or the laundry room. 

I also read that are drywall should not touch the wall and have a 1/8 inch Gap around the whole ceiling permit vibration sound. Does anyone have any other tips or tricks that I have not listed?

Upstairs we have four children, who are quite rambunctious, so we will alert the new tenants to this fact, but are trying to lessen the impact of noise as much as we can. We plan on living in this basement apartment once the kids are gone and want it to be done right!

And for your laugh of the day, when tearing down the drywall ceiling, we found that there are at least four sheets of 5/8 chipwood / MDF screwed to the ceiling. It has been textured and we had no idea it was not sheetrock. Quite the surprise!

Thanks for your ideas, tips, and suggestions.