Super Soundproofing Community Forum

Soundproofing Forum Topics => Sound Control if you're Renting - Apartments, Condo, ETC => Topic started by: afry316 on April 14, 2018, 08:23:41 PM

Title: Duplex: Soundproofing between floors, next steps?
Post by: afry316 on April 14, 2018, 08:23:41 PM
Hello -

This community is awesome. I have read numerous stories and learned a lot, my only regret is not finding this website sooner :-o

My story/request:

I have a duplex, which is split level and is of brick construction (exterior walls) and solid wooden joists. I live in the bottom portion and rent out the top. The entire upstairs is carpeted/padded except for the kitchen. The kitchen happens to be above my bedroom. In the past this was not a problem, but my new tenants work late (dont come home til 10-11) and then they are stomping around in the kitchen. I have talked to them about being quite and honestly I am not even sure if its them at this point or just the poor construction. Once I realized this problem I scrambled to fix it in several attempts.

Attempt 1: I cut holes at every joist and blew in insulation. This worked good for the airbone noises. I could not really hear anyone talking or any noise like that. However, I could still hear them walking around and dropping things.

Attempt 2: I found out about Green Glue and read that adding mass to the ceiling would lessen the vibrations. So, I added two layers of 5/8 drywall to the ceiling with green glue sandwiched in between. This helped a bit, but not a dramatic improvement. Airborne noises are virtually non existent, but the impact noises were still easily heard.

Attempt 3: I asked the tenants to let me know when they were going on vacation and I would do some improvements upstairs. The kitchen floor was porceline tile, which was on cement board that was screwed directly to the wooden subfloor - no underlayment. So what I did while there were gone was I installed a floating lament floor on top of the tile floor. I used a premium wool underlayment underneath the floating floor, which claimed high IIC numbers. This seemed to work well. It definitely dampened the impact noise but I can still hear it. Its not terrible, but I have become fixated on figure this out once and for all.

So that takes me to today. I am not sure where I should attack this problem from now. Should I installed a vinyl floor on top of the floating with a better underlayment? Should I throw in the towel on my bedroom ceiling and do a decoupled ceiling? Any suggestions on what would be the best approach?

Thanks for listening!


Title: Re: Duplex: Soundproofing between floors, next steps?
Post by: Randy S on April 16, 2018, 06:30:19 PM

In order to reduce impact noise you have to decouple somewhere.. either the ceiling below or the floor the end as you can see decoupling is the only principle that provides the best perceived reduction of impact.

also remember if you decouple from the ceiling you could have some slight impact coming from the walls after the project is complete..normally in the field I find this to be minimum.

Randy S.
Title: Re: Duplex: Soundproofing between floors, next steps?
Post by: afry316 on April 19, 2018, 03:41:18 PM
Randy -

Thank you very much for your reply. I am quite familiar with your recommendations on how to decouple a ceiling as I have read quite a few of your posts. However, I have not found anything regarding your recommendation (process & products) for decoupling the floor. Would you mind either pointing me to a post or giving me a quick rundown on how to achieve floor decoupling.

Also, which do you think would be more effective in reducing impact noise - floor decouple or ceiling - if you HAD to choose.

Thank you sir!!
Title: Re: Duplex: Soundproofing between floors, next steps?
Post by: Randy S on April 19, 2018, 03:51:55 PM
Soundproofing at the source will always deliver the best reduction.

Flooring systems are normally reviewed in detail prior to system recommendations. The systems require enough space to raise the new floated floor anywhere from 1 1/8" to 2.5" lift before final flooring.
you can see some of the decouplers here on this page.

It would best just to reach me direct when you have some time to discuss the particulars that way the right system can be recommended.

Randy S.