Isolating Airborne Noise Through Ceilings
Depending on the frequency range in question, the options for treating airborne noise from below can be limited. Whether the structure is of wood or concrete, adding resilience will be the best option to counteract the mass and rigidity of the ceiling.
WHAT WILL WORK
In order of highest to lowest performing
Decoupling will always provide superior isolation over all other methods or products. This is especially true when soundproofing your ceiling where most products have little to no effect. The most efficient way to decouple your ceiling in terms of installation and minimal head room loss is with the GenieClip® RST or HushFrame Raft. With this option, we strongly recommend removing existing drywall and attaching the GenieClips® RST directly to the joists for maximum performance. View the GenieClip® RST or HushFrame Raft.
DAMPING WITH DECOUPLING
While Green Glue Compound has limited value in a fixed drywall ceiling, on resilient clips or resilient channel, the addition of Green Glue Compound is significant. This is because damping compounds, like Green Glue Compound, are efficient when in resilient assemblies that allow the drywall to flex, thus allowing the Green Glue Compound to shear and work as intended. View Green Glue Compound tubes or Green Glue Compound pails.
Green Glue Compound on a fixed drywall ceiling will provide benefit only to airborne noise isolation. The high performance of Green Glue Compound in walls does not translate as well in soundproofing existing ceiling. The gains in mid to high frequency ranges will be noticeable, but not significant. While the gains in low frequency isolation will not be noticeable. View Green Glue Compound tubes or Green Glue Compound pails.
MASS LOADED VINYL
Depending on expectations, mass loaded vinyl alone may be enough for your project. This material will not help with isolation of low frequencies, but will help resolve typical resonance issues found in common construction materials. Contrary to popular belief, the mass of the vinyl is insignificant relative to the structure. How the vinyl resonates differently (essentially no resonance) than the other materials in the wall is what creates the value of the vinyl. View the TotalMass MLV.
Combining decoupling with damping will increase performance significantly. Mass loaded vinyl can also be used with Green Glue Compound if sandwiched between two layers of drywall. Sound tests of mass loaded vinyl in a resilient clip system show little to no gain.
WHAT WILL NOT WORK
In no particular order
ADDING A LAYER OF DRYWALL
An additional layer of drywall will do little for effective soundproofing. If the drywall layers quadruple, then some decent gains can be reached. This means a standard single drywall layer ceiling would need four layers for even noticeable gains.
Including sound board in a wall or ceiling is about as valuable as adding a layer of drywall.
LOW LEVEL PRE-DAMPED DRYWALL
Some pre-damped drywall performs well, but is hugely expensive and difficult to install. The versions found at leading hardware stores are cheaper and easier to install, but do not perform exceptionally well. Any chance of pre-damped soundproof drywall for ceilings working to isolate airborne noise in a ceiling would require the ceiling to be suspended from resilient sound clips or resilient channel, limitations similar to that of Green Glue Compound.
Insulation is necessary in partitions to avoid resonance issues (basically a drum effect), but provides little isolation of airborne noise.
FOAM STRIPS, NOISEPROOFING TAPE, OR SIMILAR ON STUDS
These tapes, whether a foam material or rubber, will not help to isolate sound. The drywall screws or nails will penetrate the foam directly with the pressure of fastening compressing the foam as if it were not even there.