I moved into a townhome in 2011 and my shared-wall neighbors are extremely noisy (the police have been here numerous times regarding noise). My builder sent the results to me of the noise transmission building code test, and the structure exceeds minimum requirements. The walls do seem exceptionally thin, however, as besides loud music I can hear people talking through the walls. Do you think it is worth it to have a second test performed, and if yes, do you know who can do this?
Thanks
You need to tear down the existing wall and install sound proof material behind new sheetrock. Why test if you can hear the person talking then it needs fixed.
Or you could just cover your walls with sound board and an additional layer of drywall. Less messy that way.
Recommended Isolation Level
An assembly rated at STC 50 will satisfy the building code requirement, however, residents could still be subject to awareness, if not understanding, of loud speech. It is typically argued that luxury accommodations require a more stringent design goal (as much as 10dB better – STC 60). Regardless of what STC is selected, all air-gaps and penetrations must be carefully controlled and sealed. Even a small air-gap can degrade the isolation integrity of an assembly.