Monday, December 05, 2005

Soundproofing a Ceiling with existing Drywall

The most often asked question we receive here at Soundproofing America is "How do I soundproof my ceiling from impact noise (footfalls) and low bass and TV sounds"? If you ask the experts they will all tell you that soundproofing from impact noise is one of the most difficult things to do. I have to agree, but we have found some effective alternatives for soundproofing a ceiling that do not require the use of resilient channels or sound clips.
We all know that you can't just slap up a layer of the standard mass loaded vinyl to your existing sheetrock and simply drywall over top. This would great if it worked, but MLV needs to be able to move or resonate with the sound. This is something we have discovered over time and field tests. There is a very simple method that does indeed work for knocking down up to 75% of the impact noise from above. This method requires the use of a product that was basically designed as a carpet underlay. It is a mass loaded vinyl with a standard or a premium decoupler that is actually bonded to the vinyl itself.
Here's the way it works, you can nail the MLV with decoupler to the ceiling using roofing nails (the ones with the large plastic heads) then caulk the seams as well as the perimeter, you'll then tape the seams with an MLV sealer tape (all available at Soundproofing America).
The manufacturer of this product recommends leaving a 1/8" gap around the perimeter when you install the MLV as well as leaving the same 1/8" gap when you drywall over top of this product. The gap will be caulked in with the acoustical caulking and you will also want to butter all 4 edges of each sheet of drywall before you install it to the ceiling. This will insure that your ceiling is sealed properly but still offers a degree of resilience or movement. Now when install the MLV with the decoupler directly to the ceiling, you will always have the foam backing facing the existing drywall ceiling. You will also be cussing me out every step of the way because this vinyl is a heavy limpid material.
There is another way to install this in 2 easy steps. Purchase the drywall (usually 5/8" thick) and then glue the MLV to the drywall. Make sure you glue the vinyl side to the drywall, leaving the foam exposed. Now it is just a matter of screwing up the MLV backed drywall to the ceiling. It is still important to butter the edges of the drywall with the acoustical caulking, and also imperative that you leave the 1/8" gap around the perimeter so that the drywall and the vinyl do not touch the adjoining walls. This system actually allows the drywall and the vinyl to resonate as the sound comes down from the floor above. This system works well for both airborne and impact noise and is an alternative for sound clips or resilient channels.
I hate giving away trade secrets, but I have found from experience that an informed customer is a good customer. This is not a "cure all" but depending on the structure of your ceiling can afford up to a 75% reduction in Impact and airborne noise.
For more information on this and other soundproofing procedures, please call the Pros at Soundproofing America.
Thanks for reading and learning together.

As Always,

Bob O.
e-mail: dr.bob@soundproofingamerica.com Call Toll free (877) 530-0139

Soundproofing, Sound proofing, Acoustical treatments, basement soundproofing, Cheap soundproofing, Commercial soundproofing, DIY soundproofing, Garage soundproofing, Home soundproofing, Home studio soundproofing, Home theater soundproofing, Industrial soundproofing, Mass loaded vinyl, Noise reduction, Residential soundproofing, Room soundproofingCeiling soundproofing, Soundproof flooring, Studio soundproofing, Wall soundproofing, Construction soundproofing, building soundproofing, soundproof floors, construction soundproofing, Acoustiblok soundproofing, soundproofing materials.