I am planning to build a new soundproof wall between two rooms. There is continuous strapping between the rooms in both the ceiling and sloped ceiling.
The ceiling construction is:
- Mineral wool (170 mm in sloped ceiling, 315 mm in ceiling)
- Vapor barrier
- Strapping 28x75
- Ceiling gypsum 9 mm (with unfilled v-joint)
I plan to slit the ceiling gypsum at the new wall, i.e., between the edge profiles' rubber strips (Gyproc ACOUnomic), but not slit the strapping.
One of the rooms will have a skylight, where sound will likely reach the strapping via a window reveal in PVC and vapor barrier.
How much flanking transmission is expected through the strapping and the air in the strapping?
Can I hope for a total R'w 44 dB for wall and flanks together? Given a wall with R'w 48 dB (Gyproc XR 70 NN-NN M45)
For me, only frequencies with human speech are relevant to isolate.
Do the skylight reveal and the ceiling gypsum's unfilled v-joints have a significant negative impact on the flanking transmission?
