>> The walls the sit in front of foundation walls will be 2x4 construction with RC, fiberglass insulation and double dry wall (1/2 and 5/8) screwed and green glued.
I am not sure if it is completly necessary (money wise) to use RC with GG on the concrete foundation walls. The only way sound will travel from the walls to upstairs is through the TOP of the wall that is attached to the ceiling joists.
I would say that Double drywall with GG would be enough for the concrete foundation walls.
All in all, you have an AWSOME idea of what is needed to attain the STCs you want.
>>The side wall adjoining the living space will be double 2x4 construction (1" gap), RC on the wall inside the HT, both walls insulated and double dry wall on both sides (different thicknesses, gap at top and bottom, same as above). This wall will have an exterior grade metal door with a weather seal in it. (Unfortunately, it will be located in the front half of the HT, just ahead of the first row of chairs.)
The double studded wall system ALONE with double drywall on each side and NO green glue yields an STC of 63. Adding GG will probably get you over 70 STC. I tried looking on the GG website, but could not find a test with double studded and GG.
I don't think you need to do RC on this wall if you are doing double studding. It would probably be a waste of money because your studs are not touching the other wall, RC is designed to stop sound transfer through the studs, and since you have a completly separate wall on the other side, RC will do little to nothing.
What you could do aswell is double drywall and GG the other side of the double studded wall (on the rec room side). That would make that wall literally commercial theatre quality sound proofing.
3) The ceiling will be heavily insulated (6"+), 1#/ft mass loaded vinyl, RC double dry wall (similar to walls). I plan on building a 1’ soffit around the outer 3” perimeter so that the recessed lights will not penetrate the ceiling.
Are you going to Green glue the ceiling between the double drywall? I would suggest this.
Mass loaded vinyl will not outperform double drywall and Green glue (MLV is around 45 STC, Double Drywall and Green glue is 54 STC). If you also add RC to the ceiling combined with double drywall and GG, you will get really good results. (I think around 60 STC)
4) For the floor, I’m considering either using 2#/ft mass loaded vinyl under the carpet and mat or a floating floor using the pads and two layers of sub-flooring. (I’m strongly leaning toward the mass loaded vinyl route.)
Since you are on concrete foundation, I don't think you need anything special on the floor unless you have ducts that are traveling through the cement floor to other areas of the house. In which case the mass loaded vinyl would probably be enough.
I would say, all in all, you will have an AWSOME theatre. Do alot of research on greengluecompany.com for construction tips, they know ALOT about sound isolation and can guide you through everything.
Last edited by Hutzal; 11/23/06 04:00 PM.
