Hey guys, newbie here. Been hanging around a while getting lots of info. I'm starting my dedicated theater room. here's the specs...15x20 with 9.5 foot ceilings. This is in a basement, but a seperate room. The front wall and both sides are concrete block walls. I'm struggling with what to do here. Should i frame out the walls and then cover them with my fabric panels, or just mount furring strips or 2x4's to the walls then install my padding aand panels? Heck the concrete doesn't let alot a sound pass through or vibrate it to begin with. Any recomendations?

Frame out all the walls making sure that the wall frame doesn't make contact with the concrete walls. Decouple the wall frames from the ceiling joist using RSIC-IV clips.

do i need to dd/gg it at that point or can I insulate and fabric over the framing?

GEE, at this point is drywall even necessary? Its going to get covered up by my insulated fabric panels. Can i use plywood instead, as I have acces to an infinite amount at no cost!

Frame out all the walls making sure that the wall frame doesn't make contact with the concrete walls. Decouple the wall frames from the ceiling joist using RSIC-IV clips.

If soundproofing is a goal, then this is exactly what you would do.

Plywood would work, especially if free... Just use heaviest you can get.

Clips are the DC-04 http://www.soundproofingcompany.com/index.php?/library/rsic_dc04_datasheet

You are not concerned with sound going through the concrete block. You are concerned about sound getting into that air cavity between the block and the drywall (plywood in your case). The sound will simply scoot straight up into your joists.

thansk for the info! Any clue on spacing for those clips connecting a 2x4 wall to concrete block?

Hi. The clips connect the top plate of the new 2x4 wall to the joists. Generally every 3-6 feet, depending on your preference

Plywood would work, especially if free... Just use heaviest you can get.



Thats sounds interesting. Would it be alright to use plywood as the first layer and then GG and some drywall on it. It would be easy to hang things on the wall then. :) Would 3/4" plywood and 5/8" drywall be overkill? Would it weigh too much to use that on a clipped & channeled ceiling?

3/4 ply + 5/8" DW = excellent

How about if you nail 2x's to the block wall (firring strips) keeping them from directly contacting the floor joists above, and fill the void between them with rigid insulation which is recommended anyway? Does that address the "flanking" issue?

I would love that idea, as the room seems tight to me already with the furniture in it. Can't think of making it smaller by another foot or so in width by doing all the framing.

3/4 ply + 5/8" DW = excellent

why bother with the drywall then? Dont need it for visual appearance as it will be getting covered up with fabric anyhow

why bother with the drywall then? Dont need it for visual appearance as it will be getting covered up with fabric anyhow
It provides extra mass, which will lower the wall resonant frequency and give you improved sound isolation. Many people use two layers of drywall (2 x 5/8" or 1/2" + 5/8"). Building code wise, you could have a problem with a plywood interior wall surface. Drywall doesn't burn.

Regards,
Terry

Drywall doesn't burn.

Regards,
Terry

Huh ? :eek:

How about if you nail 2x's to the block wall (firring strips) keeping them from directly contacting the floor joists above, and fill the void between them with rigid insulation which is recommended anyway? Does that address the "flanking" issue?

The small air cavity that is created will be problematic. You really need a deeper air cavity. Also, rigid insulation isn't what we want either. Great for thermal, not so for sound.

Huh ? :eek:
Okay, because of its paper facing it is in it's own official NFPA category of "limited-combustible."

- Terry

You can buy fire rated 5/8 drywall that gives you extra time to escape ( actually a requirement in multifamily construction ) ... but it is not " fireproof "

Regular drywall will burn just as quick as wood

also think of all the basements you have been in with that lovely wood panelling :p

There are no restrictions in our area regarding using wood as panelling ... check your local codes but if you can get plywood for free ( that did not fall off the back of a truck ;) ) then I would say go for it ... the only thing is how dense it is in comparison to drywall


just build a 2 X 4 wall with DC04 clips ... fill with the fluffy pink insulation ... and if you can get free plywood use 2 layers of 3/4" with Green glue in between

Ted already has your order ready for shipping :p:D

Products used for interior sheathing must comply with a long list of IBC and IRC codes and be certifed for that specific use by ICC-ES, Architectural Testing CCRR or other accredited certification and testing labs. These would include, but not be limited to, racking and shearing testing (ASTM-E 72-02), seismic, wind loading, fastener tests (etc, etc, etc) and, in particular NFPA 286-06, ASTM-e 84 and others (Corner burn, flame spread, barrier, etc).

Drywall meets the class A rating for use as an interior sheathing when applied to the specifications in the testing report. Some drywall is specifically tested and certified for use as a fire barrier but must be specifically certified as a barrier meeting IBC requirements. Not all plywood sheathing will meet Class A requirements (none that I know of meet fire barrier requirements). I have seen some plywood meet the requirements when coated with an intumescent paint.

Check with your local authority to see if plywood is accepted in your area as an interior sheathing. In some cases it is, in other cases only when covered with drywall.

Well Dennis after listing off all those codes and certifications you forced me to call the city and " make sure " :p ... as I suspected regarding basement development the only requirement ( here ) is to protect the vapour barrier so plywood ( or drywall ) would be more than adequate so 2 layers of plywood would be even better in the inspectors eyes. There are no fire retardant requirements for a standard basement development so that is a non issue IMO

As I mentioned above check with your local codes ;)