Author Topic: Party Wall in brand new condo blocks no noise. 2.5" fiberglass insulation.  (Read 5085 times)


  • Guest
I need some expert advice. I just bought a brand new condo and the party wall in my bedroom blocks no noise from the poeple next door, and they are by no means loud. I can hear them snoring, I hear their conversations, I hear every little movement. The building was finished in 2006 and says the following in my Purchase Agreement:

Party Walls between units -
Type of insulation: fiberglass
Thickness of insulation: two and one half inches (2.5")
R-Value of insulation: not applicable (7.75)

I would think with 2.5" fiberglass I shouldn't hear my neighbor snoring. Am I wrong??

I've been here less than a year and can't take it anymore. I want to approach the developer/management company and insist that something is wrong.

I would really appreciate any advice or guidance on what I can do to have the wall tested or how I should approach the builder and what kind of response I might expect from them.

Thank you...

Mark Daveis

  • Guest
Re: Party Wall in brand new condo blocks no noise. 2.5" fiberglass insulation.
« Reply #1 on: February 28, 2008, 01:10:55 PM »
2.5 inches of fiberglass does not have much mass so wont give much soundproofing.
A golden rule of soundproofing is that if it does not weigh much it wont stop much.
Only 2 things really matter mass and isolation (such as an airspace).
You need to use heavy materials and a air gap for best performance. :)


  • Guest
Re: Party Wall in brand new condo blocks no noise. 2.5" fiberglass insulation.
« Reply #2 on: February 29, 2008, 02:11:39 AM »
Sounds like your builder did a shoddy job. 

It would be expensive, but maybe hiring an acoustical consultant is a good idea.  He/she can both test the wall and inspect it for construction deficiencies.  Maybe he'll have a solution that won't cost thousands, who knows.

You might also want to contact your local building dept.  A multifamily dwelling is supposed to achieve STC 50 between units, and at that level, you shouldn't hear much at all from next door.  If you have solid, third-party evidence that the builder didn't do his job, you'll have the legal teeth to get him to fix it. 


  • Guest
Here's something that really works!
Add a layer of 1/8" MLV with pressure sensitive adhesive back (PSA) directly to existing wall.  Tape the MLV butt seams with metal seam tape and caulk perimiter.  Then add a layer of 5/8" fire code dry wall with Green Glue squiggled on it (2-3 tubes/4x8 sheet) and screw it on (to existing layer of dry wall - you do not need to go to studs).  Although it has not been "lab tested", field results have been spectacular.  Poeple who have had contractors build them a home recording/practice studio where neighbors have complained (and in some cases called the authorities) have fixed their walls/ceilings using this method - no more boom boom or blare blare.