challenges of floor soundproofing and coping with elevation - AVS Forum | Home Theater Discussions And Reviews
Forum Jump: 
 
Thread Tools
post #1 of 11 Old 11-12-2018, 01:37 PM - Thread Starter
Advanced Member
 
niccolo's Avatar
 
Join Date: Aug 2011
Posts: 734
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 267 Post(s)
Liked: 67
challenges of floor soundproofing and coping with elevation

I'm doing some partial soundproofing on a lower-end home theater build. I'm enclosing a loft space on the second floor of a wood-framed, newer construction house. I'm trying to figure out how to treat the floor at modest cost and within building code constraints.



And before everyone piles on me for not doing complete room-within-a-room construction, how the chain is only as strong as the weakest link, would I build a leaky fish tank, etc., I'm clear on the trade-offs I'm making. My thinking is that even a full-on soundproofing build would be significantly compromised in that second-floor space in this wood-framed house. And I'm not really in a position to do that full-on build at this time. And I'm okay doing some combination of more moderate SPL listening and using headphones as needed. But it still seems to me that some soundproofing efforts are warranted.


My original thought was to put a layer of rubber (of a thickness to be determined) down on the OSB subfloor, then put a second subfloor (OSB or plywood or MDF/HDF), and then a carpet pad and carpet on top of that. My thinking is that a suspended subfloor would be fairly helpful in reducing noise transmission into the bedroom below and the house framing more generally. I was also thinking of blowing some non-rigid insulation in if possible, to reduce the cavity resonance, because unfortunately the builders didn't put any insulation between the floors; but if I do that, I'm clear it would make only a very modest soundproofing difference.


My challenge is that my contractor says building code limits us to 1/2" height differential between the finished floor, whether we put a ramped or stepped transition in. I have 1/2"+ of engineered wood over underlayment outside the room in the hallway, so the final floor in the room can be a bit over 1" above the current subfloor. But if I put down 1/4" rubber (I know it's thin, but it should still significantly decouple) and float a second 1/2" or 5/8" subfloor over that, I'm already getting close to the full inch I have to work with. I'm also confused about how carpet does or doesn't count toward that inch, e.g. if I have a 1" plush carpet, I'm assuming the full inch doesn't count, just some fraction of it.



Suggestions?

Benq W1070 projector w/ Chief RSM mount with custom interface bracket
119" Da-Lite Cinema Contour with High-Contrast (gray) Da-Mat screen
Denon X2000 receiver fed by Panasonic DMP-BDT210 Bluray player
Focal Chorus 700-series towers and center, JMLab Tantal 500-series bookshelf rears
Rythmik FV15HP sub

Last edited by niccolo; 11-12-2018 at 01:40 PM.
niccolo is offline  
Sponsored Links
Advertisement
 
post #2 of 11 Old 11-12-2018, 02:07 PM
HOME THEATER CONTRACTOR
 
BIGmouthinDC's Avatar
 
Join Date: Jan 2003
Location: Northern VA
Posts: 32,141
Mentioned: 436 Post(s)
Tagged: 5 Thread(s)
Quoted: 5842 Post(s)
Liked: 5411
Quote:
Originally Posted by niccolo View Post
My challenge is that my contractor says building code limits us to 1/2" height differential between the finished floor, whether we put a ramped or stepped transition in.

I'm not sure this is true. It is worth investigating rather than taking his word for it. Many theater projects have had more than an inch differential.
BIGmouthinDC is offline  
post #3 of 11 Old 11-12-2018, 02:15 PM - Thread Starter
Advanced Member
 
niccolo's Avatar
 
Join Date: Aug 2011
Posts: 734
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 267 Post(s)
Liked: 67
Quote:
Originally Posted by BIGmouthinDC View Post
I'm not sure this is true. It is worth investigating rather than taking his word for it. Many theater projects have had more than an inch differential.

I wondered about this, and steps show up in various ways in various contexts in homes, so I don't see why a step at a room entrance would be out of the question. I suppose another option is to build up a landing outside the doorway, so that the floor height of the landing matched the floor height inside the room.



One of the challenges is that our local building department is an utter clusterfumble, so I'm hesitant to raise, or have the contractor raise, the issue with them.


Or maybe I let the idea of doing some soundproofing on the floor go; my build is rather soundproofing-compromised anyway, so investing a lot in a more soundproofed floor may not make much sense when the wall framing can channel vibration right around that floor. One option is to put the same underlayment plus engineered wood down in the room that's outside the room currently, and then put a nice area rug down on top of it.

Benq W1070 projector w/ Chief RSM mount with custom interface bracket
119" Da-Lite Cinema Contour with High-Contrast (gray) Da-Mat screen
Denon X2000 receiver fed by Panasonic DMP-BDT210 Bluray player
Focal Chorus 700-series towers and center, JMLab Tantal 500-series bookshelf rears
Rythmik FV15HP sub
niccolo is offline  
Sponsored Links
Advertisement
 
post #4 of 11 Old 11-12-2018, 02:21 PM
HOME THEATER CONTRACTOR
 
BIGmouthinDC's Avatar
 
Join Date: Jan 2003
Location: Northern VA
Posts: 32,141
Mentioned: 436 Post(s)
Tagged: 5 Thread(s)
Quoted: 5842 Post(s)
Liked: 5411
yes sudden transition at the threshold is limited but with a ramp up or landing it should work.
BIGmouthinDC is offline  
post #5 of 11 Old 11-12-2018, 06:26 PM
Advanced Member
 
mhutchins's Avatar
 
Join Date: Aug 2006
Location: Austin, TX
Posts: 959
Mentioned: 14 Post(s)
Tagged: 1 Thread(s)
Quoted: 252 Post(s)
Liked: 237
Have you considered doing clips and channel with double drywall and Green Glue on the ceiling below? This might buy you more transmission loss and you don't have to worry about the step up into the room.


Mike
mhutchins is offline  
post #6 of 11 Old 11-12-2018, 09:25 PM - Thread Starter
Advanced Member
 
niccolo's Avatar
 
Join Date: Aug 2011
Posts: 734
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 267 Post(s)
Liked: 67
Quote:
Originally Posted by mhutchins View Post
Have you considered doing clips and channel with double drywall and Green Glue on the ceiling below? This might buy you more transmission loss and you don't have to worry about the step up into the room.


Mike

Interesting point. My concern there is that this would leave sound/vibration free to travel into the floor framing and from there throughout the house, including into the wall framing of the room below. And at this point I'm doing a low-budget build, so clips and channel aren't in the cards anywhere.


Then again, even if I put in an isolated subfloor, I'm still left with walls that are mostly coupled, and through which sound will travel. Half measures like I'm contemplating will really only yield very modest results.


Then again, even if I did a proper room-within-a-room build, on the second floor of a wood-framed house, my guess is the soundproofing wouldn't be stellar.


I think I'm going to have to live with some combination of modest listening levels, everyone in the house joining in for movie nights, or headphones.

Benq W1070 projector w/ Chief RSM mount with custom interface bracket
119" Da-Lite Cinema Contour with High-Contrast (gray) Da-Mat screen
Denon X2000 receiver fed by Panasonic DMP-BDT210 Bluray player
Focal Chorus 700-series towers and center, JMLab Tantal 500-series bookshelf rears
Rythmik FV15HP sub
niccolo is offline  
post #7 of 11 Old 11-23-2018, 08:30 PM - Thread Starter
Advanced Member
 
niccolo's Avatar
 
Join Date: Aug 2011
Posts: 734
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 267 Post(s)
Liked: 67
Quote:
Originally Posted by niccolo View Post
Interesting point. My concern there is that this would leave sound/vibration free to travel into the floor framing and from there throughout the house, including into the wall framing of the room below. And at this point I'm doing a low-budget build, so clips and channel aren't in the cards anywhere.


Then again, even if I put in an isolated subfloor, I'm still left with walls that are mostly coupled, and through which sound will travel. Half measures like I'm contemplating will really only yield very modest results.


Then again, even if I did a proper room-within-a-room build, on the second floor of a wood-framed house, my guess is the soundproofing wouldn't be stellar.


I think I'm going to have to live with some combination of modest listening levels, everyone in the house joining in for movie nights, or headphones.
Decision time, contractor needs to know next week in which direction I want the door hinged, even if we postpone the actual built-up floor for now. 3/4" horse stall mat is back in stock at my local tractor supply store, I'm thinking of gluing that on the existing subfloor and then gluing a layer of OSB/MDF/plywood (contractor is arguing for HDF, i.e. higher density MDF) on top of that, and maybe a second layer, maybe with Green Glue, because I think that shouldn't add too much cost and the extra mass might make a real difference. But I have to decide what to do at the door threshold. Options:


1) Build a step/landing outside the door, so the elevated theater height floor would continue just outside the door into the hallway (which is plenty wide to accommodate a step). This would involve some extra construction, and the aesthetic awkwardness of a step outside the door. But it would be building code compliant and the least trip hazard.



2) Put the step up/down at the transition, with the door hanging lower at hallway floor height, opening out into the hallway. This would be somewhat helpful from a soundproofing perspective--the door could seal against the vertical part of a carpeted step--but a trip hazard I'd have to warn people about, and not code compliant, so either the inspector would have to not care (which it appears may be the case) or it would have to be done after the inspector did their final inspection. And if I sold the home it might become an issue.


3) Put the step up/down at the transition, but hinge the door in. This would basically look like a typical front door of a house (where you have to step up a few inches to keep rainwater out of the house). It would be visually more obvious, hence less of a trip hazard. If necessary, one could always add a step or ramp outside the door later.


It's probably worth mentioning that there's also a closet in the room--which for now I'm not using as an equipment closet, just general household storage--that will have to be stepped, too, though it will get less frequent use.


It's so helpful to have this forum to talk this stuff through. I didn't say it at the Thanksgiving table yesterday, but I'm thankful for you guys!

Benq W1070 projector w/ Chief RSM mount with custom interface bracket
119" Da-Lite Cinema Contour with High-Contrast (gray) Da-Mat screen
Denon X2000 receiver fed by Panasonic DMP-BDT210 Bluray player
Focal Chorus 700-series towers and center, JMLab Tantal 500-series bookshelf rears
Rythmik FV15HP sub
niccolo is offline  
post #8 of 11 Old 09-15-2019, 09:48 AM
AVS Forum Special Member
 
jjcook's Avatar
 
Join Date: Dec 2004
Location: Portland, OR
Posts: 1,088
Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 468 Post(s)
Liked: 189
Quote:
Originally Posted by niccolo View Post
Decision time
@niccolo What did you end up doing for the floor elevation transition?
jjcook is offline  
post #9 of 11 Old 09-15-2019, 07:29 PM - Thread Starter
Advanced Member
 
niccolo's Avatar
 
Join Date: Aug 2011
Posts: 734
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 267 Post(s)
Liked: 67
Quote:
Originally Posted by jjcook View Post
@niccolo What did you end up doing for the floor elevation transition?

Ha, I didn't. We were able to schedule the final building department inspection/sign-off without having the floor done or a door hung, and the contractor got busy with other stuff, so the project got put on hold.


But my current thinking is to glue down 3/4" hose stall mat over the OSB subfloor, and probably two layers of OSB/plywood/particle board floated over that. On the transition, I've basically decided to go with option #3 , having the door swing into the room and a small step up in the door frame, kind of like the exterior doorway into a house.

Benq W1070 projector w/ Chief RSM mount with custom interface bracket
119" Da-Lite Cinema Contour with High-Contrast (gray) Da-Mat screen
Denon X2000 receiver fed by Panasonic DMP-BDT210 Bluray player
Focal Chorus 700-series towers and center, JMLab Tantal 500-series bookshelf rears
Rythmik FV15HP sub
niccolo is offline  
post #10 of 11 Old 09-22-2019, 06:14 PM
AVS Forum Special Member
 
jjcook's Avatar
 
Join Date: Dec 2004
Location: Portland, OR
Posts: 1,088
Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 468 Post(s)
Liked: 189
@niccolo I'm looking forward to how it turns out -- good luck! Thanks.
jjcook is offline  
post #11 of 11 Old 09-22-2019, 08:36 PM - Thread Starter
Advanced Member
 
niccolo's Avatar
 
Join Date: Aug 2011
Posts: 734
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 267 Post(s)
Liked: 67
Quote:
Originally Posted by jjcook View Post
@niccolo I'm looking forward to how it turns out -- good luck! Thanks.

Thanks! With building permit delays, contractor scheduling headaches, and personal stuff, it's pretty amazing how long even fairly simple projects can drag on

Benq W1070 projector w/ Chief RSM mount with custom interface bracket
119" Da-Lite Cinema Contour with High-Contrast (gray) Da-Mat screen
Denon X2000 receiver fed by Panasonic DMP-BDT210 Bluray player
Focal Chorus 700-series towers and center, JMLab Tantal 500-series bookshelf rears
Rythmik FV15HP sub
niccolo is offline  
Sponsored Links
Advertisement
 
Reply Dedicated Theater Design & Construction

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off