2. tech-talk
  3. 119545-501

Treating Floor in New Construction - Reducing Footfall and Vibration

Looking for some good ideas/solutions to treating my new dedicated music room's floor.  The room will be fairly large at 22w x 29L, built on the main floor of the new house with a basement below.  My current room is in my basement with concrete floors so footfall is never an issue.

I have asked the engineering firm to give me some recommendations on making the floor stronger structure wise; not sure what they will suggest, maybe floor joist on more narrow centers, say 12 inch vs 16.  

Have you tackled this issue?  What about mass loaded vinyl (MLV); would a layer of heavy vinyl between the OSB floor boards and carpet pad help?  Use two layers of OSB flooring and glue them together?  Ideas?

stickman451
ptss
1,964 posts
 
Instead of 2 x 5/8 drywall I experimented with 1 x 5/8 MDF under 1 x 5/8 drywall and was amazed at the improvement overall.  I used adhesive on the studs, probably PL400,can't remember. That's how I would go now,all around.  Seemed to put the sound on steroids for clarity,dynamics,nuance and overall sense of aliveness.The room was incredibly "quiet". What about your ceiling?
ptss
1,964 posts
 
Also,forgot to mention. Re the floor; 3/8 plywood glued and screwed to the underside of the joists gives 'tremendous' boost to rigidity and is how I would go if building new or renovating today. Between floors I like a second layer of press fit insulation resting on the plywood base.
I'm with needlefree re the benefits of QuietRock drywall. They claim 1 sheet of their 5/8 is equal 7 sheets of normal drywall if I remember correctly. 
ptss
1,964 posts
 
For decorating reasons I would go with all parallel walls. 10 foot or higher ceilings provide more flexibility for multiple levels,middle area treatment and massive crown mouldings. As a listening room I assume some sound treatments will be used for standing waves,etc. I live in the Vancouver area in Canada where it is not uncommon to install hot water radiant heating in concrete on all floors in better homes."Double" 5/8 plywood subfloor is minimum where a tile floor will be over the concrete in-floor heating of minimum 4 inches of concrete. Now the floor is stiff! and massive!! Enjoy 
last_lemming
639 posts
 
Use tongue and groove structural plywood glued and secured to floor joists with deck screws. Then use a self leveling floor system like gypcrete to a 3/4" tickness. This has about a 900 psi strength. For reference typical concrete has about 3000 psi strength. So this means the gypcrete will need to be covered. Cork is good for absorbing but it is soft. If you go wood flooring for a more lively room try to go glue down for the most rigid system. 
last_lemming
639 posts
 
Oh and cross brace you're floor joists beyond code requirements. Cross bracing is there to distribute live and dead loads to adjacent joists.  Plywood on the underside of the joist is a good helper as well.  Also at very little added cost ask them to double up or even triple up the floor joists under where the speakers will be - or even better use a glue-Lam member in liue of a open web joists as this will be substantially stronger and more rigid  then anything other than steel. 
More to discover