Answer to Question #44857 in Physics for Renuka

Question

Hi,
I reside in Mumbai on 2nd floor of a 3 storey building
We have very troublesome topfloor neighbours. Since last 25 years we have been adjusting but its becoming increasingly difficult now.
3-4 kids run on a daily basis from morning 6 am to 1 am midnight. All people stomp around whole day and they keep dragging chairs.

Can you please provide a solution by which we can treat our ceiling so that the noise is atleast reduced if not eliminated

Please note that nothing can be done on flooring of the top floor people as they are very inconsiderate and have refused the carpet option that we gave them, changing their floor with acoustic material is ruled out

so whatever, has to be done, can be done only with our ceiling

Regards
REnuka

Answer 1

· Remove the existing ceiling drywall. Why? The current drywall is in intimate contact with the ceiling joists (framing). This is undesirable. We want to attach the new ceiling drywall in a decoupled fashion.
· You might consider increasing the mass (weight) of the subfloor overhead by adding strips of heavy drywall and damping compound. Screw the drywall strips directly to the underside of the original subfloor. Take care to not use a screw that is too long!
· Install R19 fiberglass insulation between the joists. Just the standard stuff you find at the local big box store. You will get no additional soundproofing by using expensive, exotic "acoustic" insulation. There's just no independent data that supports spending more on exotic stuff. Also, you will not significantly benefit from adding more than R19. Don't over-compress, as the compression can actually conduct a vibration.
· Install a resilient system to the bottom of the joists. You will attach the new ceiling drywall to this resilient track system. This is commonly one of a number of resilient clips and standard Drywall Furring Channel. Take care to select the correct channel.
· Install two layers of standard 5/8" drywall and a damping compound to the resilient track system. Do not place screws from the drywall to the joists. Standard drywall is great, and cheap. Pre-damped "soundproof" drywall is not only expensive, it is lower performance than doing it yourself in the field.
· Seal the perimeter with quality acoustic sealant.