@turkey_hollow_rr posted:If noise becomes an issue with the foam tops it may be possible to attach something to the underside to quiet things down. Homasote if it is available, auto parts stores carry Dynamat or some other dampening material. I don't know if ceiling tiles are dense enough to make much difference but that could be worth a try.
I've discovered that the butyl rubber sound deadening mat for cars works really well on my suspended second level. I'm about halfway done with it, (the easy half) and the difference in track noise on the finished part is pretty significant.
This is the stuff I am using, I got it on Amazon.
