Retrofit Soundproofing for Garage Build

[mgent]

Looking for some advice on soundproofing... I am putting together a simulator in my garage, and before starting the install, am thinking through some ‘soundproofing’ options... I’m not as worried about transmission to the adjoining rooms on the 1st floor, as the garage was an addition, so there are already double, fully insulated interior walls separated by a solid brick (formerly exterior) wall... I am however concerned about transmission to the rooms above. The bedroom directly above is used as a game room, but my kids’ rooms are all next to that...

Currently the ceiling construction in the garage is as follows - rug over wood floors on 2nd floor bedroom, with plywood subfloors (waiting to get actual details from my builder)... Then the ceiling has 2x10 joists with 16” spacing, spray foam insulation, and 2 layers of 1/2” type X drywall. I’ve read a bunch about basically replacing the current drywall with mass loaded vinyl, isolation clips/hat channel, and 2 layers of 5/8” quiet barrier drywall w/green glue, but that raises a few questions:
- I imagine taking those steps would make mounting my EyeXO and Projector from the ceiling difficult/not possible? Those would mount to the joists otherwise, but not sure they would be able to... Would I have to build an area for both to mount and just not have that section soundproof?
- I’m not looking for complete silence, really just aiming for meaningful enough reduction it doesn’t disrupt them sleeping when hitting driver... Would I need to cover the entire garage ceiling, or can I basically cover just the area directly above the simulator (16’ wide screen back to hitting area)?
- Rather than ripping all the current drywall out, is it possible to just add the clips and channels then a layer of 5/8” quiet drywall on top of the existing - would that have similar effect?

Thanks

Mark

[Stetson]

Subscribing to this.

I believe that the big issue with decoupling and installing the sound dampening drywall to the current ceiling is the lack of strength of the drywall system already in place.

I would suggest green glue and 2 layers of drywall. Also would put as much rolled insulation as possible in the ceiling as possible, as spray foam is a great insulator but sound reduction comes through mass. Finally I would get some commando cloth and make baffles.

With a garage and an existing structure you are limited by the concrete floor, garage door and some similar factors.

[mgent]

Stetson - Thanks for the comments... If I end up opening up the current drywall, then I will look to add some rolled insulation as well... To clarify, I’m not really that focused on complete sound roofing, so that no sound escapes, or even for managing sound within the room - I solely want to reduce the amount of sound moving to the 2nd floor of our house... I plan to play most times with the garage door open, as I prefer the fresh air...

Another issue I just thought about on the clips/channel approach is the mounts for the garage door rails - I imagine those can’t be mounted to the channel, and would need to find a stud somewhere?

I have a hitting net I just got to hold me over for the next month or so until the rest of my stuff arrives - I’m going to go take some dB measurements to get an idea of where I am currently - I’ll measure dB in the garage while hitting Driver, then dB in the game room directly above, then the same in the kids’ rooms, and see where I stand as of now...

**edit - forgot to add that I’m using commando cloth for the sides of my hitting area as well - floor to ceiling...

[mgent]

Went out today and took some initial measurements so get a better sense of where I am currently... Granted, this was hitting a few drives into a Net in the garage, without any of the turf or rubber subassembly and without the side curtains up, but also without the screen... I used an app I downloaded on my iPhone called Decibel X, placed it in the room, set to record, then went and hit a few drives. Measurements were as follows:

Garage (where I was hitting, and with the garage door closed) - ‘Max’ measured 100.4 dB, ‘Peak’ measured 105.5 dB - not surprisingly, both shots are very clearly visible in the plot, and very clearly audible on the recording...

Game Room (directly above garage) - Max and Peak were both from me closing the door, but looking at the plot, both shots (middle two peaks) were sub-60 dB (~54 and 58), but were audible on the recording...

Kids Room (nearest to game room up) - Max and Peak were again me closing the door, but only one shot was audible on the recording, albeit it pretty quiet, and on the plot the one shot looks to be ~35 dB - I’m not able to identify the second shot on the recording or the plot, but no other peaks are above 40 dB...

Now I’m not sure if it’s worth doing any of the work... Using a chart from the American Academy of Audiology, 60 dB is a normal conversation or dishwasher, 50 dB is moderate rainfall, 40 dB is a quiet library, and 30 dB is a whisper... If the loudest it gets in the game room is 60, that’s not that bad, and if in the kids’ rooms it’s sub 40 then its not a problem... I imagine once there is some flooring (mix of SynRye 200 from SynLawn and a large T-section with rubber foundation by Fiberbuilt), and once the curtains are up, that will help a little bit as well, and I would guess that opening the garage door would help as well... Maybe not worth doing the retention clips, but maybe either replace existing 2x 1/2” drywall with 2x 5/8” drywall with GG, or even just add a single layer of 5/8” with GG to the existing? I’d rather be safe than sorry, as ripping out everything after it’s installed doesn’t sound very appealing...

[Stetson]

Great call on the decibel readings. The noise level in the kids room isn’t bad at all.

That would encourage me to do minimally invasive items and get that game room down to 50 and garage hopefully under 80. But as you said no need to remove drywall now

[Bobby]

Just add a layer GG and 5/8” if it’s too loud. I think that alone would reduce it by 10 decibels or more. There are a bunch of materials from GG online that might be able to give you a more official answer.

https://www.greengluecompany.com/sit...ra_drywall.pdf

Another option... put a white noise maker on low in the room above. We did that for our kids when they were younger. Worked like a charm.

[mgent]

The kids have white noise makers in their rooms already - we learned when my 1st was a baby that those are a must, and just never took them out...

I asked my contractor for quotes on adding 1 layer of 5/8" with GG to the existing 2x 1/2", and for stripping out the current and replacing with 2x 5/8" with GG... I'd rather not end up stripping the old stuff out, just because of the mess, but the advantage is that we can add supports to make mounting the Uneekor and Projector mounts easier... Screen should be here early Feb, so should be able to get it all done before...

[Daniel.Armenio]

mgent what did you end up going with here? How did the results turn out?

I am in a similar situation but my master bedroom is above the garage.

[The Horse]

Me too, subscribed. I'm going to do similar readings and report back and would love to hear of what worked.

[Daniel.Armenio]

I’m thinking for me it might be more cost effective to just try to sound proof the floor in the master bedroom. I reached out to a local sound proofing company to setup a consultation. I will report back once I talk to them.

[preludesam]

Everything I read on soundproofing suggest creating a room within a room. Creating a sealed room air gapped as many times as possible to the surrounding rooms. Do this and get as much dense material surrounding the room final air gap. The problem they said with using foam and other tricks is that’s designed to prevent reverb and not block sound completely. Like spraying water into a sponge vs against concrete. The sponge let’s the water through but stops it from bouncing around and concrete blocks everything.

[Brettster]

I've always heard that 'rock wool' is a good choice for sound-proof insulation. Regarding for the sound of the screen, you're going to have to dampen that with material behind it, unless you use a pure 'Archery Net' screen, which will reduce sound as much as possible, but result in lower quality image on screen. In which case you consider something like a Heavy Duty Sound/Blanket which I'm going to setup behind my screen, or you also add a 3"-4" thick memory foam mattress topper.

Good luck - let us know what you end up with and how it works - what your final readings are with the Decibel X App on your phone?