Sound isolation quality
Sound transmission controlled by wall/floor assembly type, insulation, air gaps, and mass. STC 50+ recommended between living spaces.
Standard
Sound transmission controlled by wall/floor assembly type, insulation, air gaps, and mass. STC 50+ recommended between living spaces.
How to check
1. Test with a sound source (radio/speaker) on one side — listen on the other side
2. Check for gaps under doors (install door sweeps or acoustic seals)
3. Verify insulation in partition walls between rooms (batts should fill cavity)
4. Check for back-to-back electrical boxes (sound flanking path — offset by one stud bay)
5. Verify outlets and switches are sealed with acoustic putty pads
6. Check for gaps around pipe and duct penetrations (seal with acoustic caulk)
7. For floor/ceiling: verify resilient channel or sound isolation clips if specified
8. Check for double-layer drywall on sound-rated walls
Common problems
- No insulation in partition walls (sound transfers easily)
- Back-to-back electrical boxes (creates a hole in the sound barrier)
- Gaps under doors (sound travels through any opening)
- Penetrations not sealed (sound flanks through gaps)
- Single layer drywall on sound-rated wall (need double layer or resilient channel)
- HVAC ducts transferring sound between rooms (need duct lining or silencers)
- Outlet boxes not sealed with putty pads