For measurable reduction in both Footstep and Airborne noise we have to make a fundamental change in the way floors and ceilings interact. The problem is that everything is screwed together; no matter how many layers there are, no matter what kind of high priced insulation is used, it is all still screwed together.
The single most effective product available to break this "screwed" connection is our QuietClips. When you are willing to remove the old ceiling, or are starting from scratch, we have the opportunity to create a much needed mechanical separation from up to down. Using QuietClips, with a standard 7/8" hat channel, you will be able to attach new sheetrock to a floated metal channel rather than the bottom of the floor joist.
Common sense tells us this is the best possible situation; vibration from footsteps and airborne noise from above cannot travel through the structure in either direction. One or two layers of sheetrock can be installed with our clips; you do not have to add any extra clips with 2 layers, you need only use a 20 gauge channel. Drywall furring channel is locally available, if you have any questions about sourcing the channel call us, we will find it for you.
One final upgrade is possible for your soundproof ceiling; we can use Green Glue between the two layers of sheetrock. Even at one tube per 32 sqft you will get a noticeable result when sound isolation clips are combined with Green Glue.
Get it right the first time!