New Studio Construction Need urgent help!

Hi I am ready to start building my Studio and have already read the Book: HOME RECORDING STUDIO Build it like the Pros. Now I have decided to build the studio using the STC 57 method of insulation shown on page 55... but I have a couple of question all of my walls in the Studio are COncrete... This book doesn't talks too much about Concrete walls and my question is: can I use the concrete wall and add insulation to it then the air space Insulation and insulation with Dry Wall?? Or do I have to cover my concrete walls with Drya wall? My Second question is... Where the concrete walls are I have Pillars ( I think that is the name of them my technical english is ot that good please refer to the pics) So they are basically hanging from outside the wall itself inside the space where the Recording Room is going to be there are 3 pillars in the right side and 2 on the Left side... How do I build my insulation around them?? Should I follow the contour they make when I build the room inside the room?? I mean should I make with Drywall the contour of the pillars?? I hope I explain myself properlly here are the pics! Regards, Roberto

Any help will be highly apreciated! Thanks

Concrete walls are your outer leaf. Now you have to build an inner leaf , in this case, wood studs with layers of drywall ON ONE SIDE ONLY, decoupled, not touching, completely independent from any wall, or existing ceiling. That will make your 2 leaf MSM system. About the pillars, yes, if you follow the shape you can save space, now you have to be creative to use that space for something or make it look good at the end.

Thanks for that!! Should I add insulation to the Concrete walls? SO basically it will be the Outer Leaf with insulation then air space... insulation and Drywall??

It doesnt matter if its insulation on one side, then air and then insulation.... The thing is you need dampening in the air caivity and it doesnt care where it is placed. If you are building "normal" walls (not inside out like john designs) then just put insulation inside the wood studs and leave the concrete wall alone

I like "inside out walls": existing concrete>air>drywall>timber frame with insulation but otherwise: existing concrete>air>timber frame with insulation>drywall is fine - just treat your room with "traps" later as needed. How is the existing ceiling made? What is above? (another room?) You might need to add mass to ("beef up") the existing ceiling - such as directly attaching some drywall, if possible. Then build your studio ceiling on top of your inner walls - not touching the existing structure. Make the existing structure absolutely airtight with an acoustic caulk/sealant. And the same for the inner structure that you will build. Include both ventilation (fans/ducts to provide air to breathe) and air conditioning (heating/cooling) at the design stage. Hope that helps a bit :) , Geoff

Hi Geoff, Actually above the ceiling there is no room I have used this type of ceiling that has insulation pre made into it so I plan to add ceiling>air>insulation> Drywall for roof... Ventilation is another issue I have to work... You have air returns between control room and Recording room? Or you guys use the same A/C duct? Thanks for the help!! Regards,

You should first MAKE SURe you can add extra mass that you ceiling can support

Totally!! Checking that with the contractor tomorrow! He is coming in to give me a quote!

oK Prepare for him telling u is gonna cost twice as you thought :P

LOL!!! Yeah have thought about that!!

I like "inside out walls": existing concrete>air>drywall>timber frame with insulation but otherwise: existing concrete>air>timber frame with insulation>drywall is fine -

But even in the inside-out case you should still have insulation in the "air" gap between the leaves, if you want maximum isolation. Not doing so will cost you around 5 to 10 dB of isolation, theoretically. It serves three purposes, two of which are: damps flutter echo and other resonance in the cavity, lowers the resonant frequency of the entire MSM system. The insulation must cover the entire surface of a leaf, and the thicker the better. - Stuart -

Ok So should I also cover the concrete walls with insulation?? I was thinking CONCRETE WALL> INSULATION > AIR SPACE > INSULATION > DRYWALL.... What you think? Regards, Roberto

How big is your air gap? How much isolation do you need? Fill the entire gap if you want to! Just don't jam the stuff in so tight that it starts bridging mechanically (flanking). As long as it lies in the gap loosely, more is better. There's a brief research paper on that somewhere here, I recall. From memory: half-filling a 6-inch gap gives you something like 6 dB isolation gain, while completely filling it gives you a 10 dB gain. (I think those figures are roughly correct, but look for the paper and check them to make sure.) In any case, more insulation in the gap is better, as long as it does not bridge, and is the right density. - Stuart -

What do you mean by Bridge? Regards

It means that you put so much insulation compressed that its acting like a mass and therefore, providing solid contact between leaves. You can attach insulation directly on the concrete walls if you want, using nails, wires, or whatever, but dont spend extra money building a frame just to hold insulation agains the concrete wall If you only put insulation on the inner leaf frame, fully filled, and have a good air space you should be fine. If not, attach some directly on the concrete if you want to be relaxed about it :)

Oh great! Yeah I though of actually attaching the insulation to the Drywall basically and air space between that and the Concrete wall Will totally leave the air gap in the middle!! Thanks for the Tips guys!