John Sayers' Recording Studio Design Forum Archive

Edited - I misunderstood the question and answered incorrectly!

My main concern is that there will NOT be as much mass on walls and the ceiling.
Would adding another layer of sheetrock to walls and ceiling help?

I just don't want to put extra money and effort unless there is an effective enough improvement.
What do you guys think?

How about this for the floor?:

Considering your space available, I'm inclined to agree with Paul; your walls/ceiling will be the deciding factor here, up to the point you could spare about 18" total thickness for two heavy leaves and at least 12" air gap.

Rather than take up nearly a foot of ceiling height with a floor that won't be matched by walls/ceiling, it would make more sense (the more I look at it) to look into just leveling the concrete (more concrete) and adding at least one more layer to each wall/ceiling leaf. (It's still going to be "fun" figuring out your outer ceiling leaf; putting both on the same framing limits air gap and mandates using RC or similar, and there is still the roof acting as a third leaf.

To see if you have moisture problems, lay a piece of thin metal (like flashing) flat against the floor for a couple of days; pick it up fairly early in the morning, and if it (and/or the floor) is damp, there's a moisture problem... Steve

Wish had more space to spare

AlexT wrote:

...building a frame (level) and filling it with dry sand... Steve

Hey Steve,
Couple of questions:
Would this “frame filled with sand” be floating on rubber pucks or just on top of the existing concrete floor?
Is sand better alternative to rockwool for my design?

Nope - it doesn't float on pucks.

It's just a great way to both level a floor without creating a drum head (which is what will happen with a deck and rockwool) and also creates a real nice chaseway to run plastic conduit for low voltage wiring from the live room to the control room.

It's what is done in a lot of pro studios when building within an existing building. I would not do it with new construction.

Rod

Thanks Steve and Rod,
I had the concrete floors checked for moisture and leveling and luckily the floor is leveled and no moisture problem.

Seems like floating the floor will do NADA for my design.
From what I understand reading the link Paul had suggested it is better to use the existing concrete floor.
According to Scenario C: Do I just layer OSB and hardwood flooring directly on top of the “existing” concrete floor?

Paul wrote:Scenario A: This is the best. BUT... only worth it if BOTH the Floating Floor AND the walls and ceiling are HEAVY. Can't have concrete? Put steel plates in the floor.

Scenario B: Is pointless. Use the money, time and effort to make the walls and ceiling much heavier, turning it into a quality Scenario C

Scenario C: 2nd best. The heavier the walls and ceiling are the closer it will get to Scenario A. Cutting the original slab in the air gap will get you even closer to Scenario A

Make sense?
Paul

hi alex, fellow bay area dude,

i'm at the exact same point as you, trying to figure out whether to leave the slab bare or somehow floor over it with some additional layer, perhaps a thin sand layer (i've pretty much decided not to float).

i know one thing, you do not want ANY airgaps of even 1 or 2 mm. i think it might be the easiest thing to go with bare slab. as far as isolation goes, there is nothing that needs to be added to the slab, it already isolates very well. that's what my research tells me.

the tough part will be building a ceiling (or even wall) that isolates as well as the slab floor does ... as knightfly has said, it will take a good 3+ inches of gypsum (in other words FIVE 5/8 inch layers ) in BOTH leaves with around a foot of airgap to approach the TL (or, actually, flanking TL) of the existing slab floor.

p.s. you are lucky to be able to keep your garage door functional, i'm going to have to block mine

dan

Thanks Dan,
You’re right; it is senseless to float.

I don’t seem to have much of a moisture problem, however would still like to raise the floor… just to be on the safe side.

I’m still not too clear about the sand technique.
Is it basically a 2x4 frame filled with sand with regular floor layers on top of it?
Is there a picture or link to how it is actually constructed?

Is it basically a 2x4 frame filled with sand with regular floor layers on top of it?

i'm assuming so ... very important not to have any air betwen the sand and the floor surface that's for sure. if you are just leveling maybe you don't need a full 2x4 thickness either ... but others may be able to give more tips ... dan

... very important not to have any air betwen the sand and the floor surface that's for sure... dan

This is exactly what I’m wondering about!
How can sand be packed so that there is no air space between the top floor surface and the sand?

AlexT wrote:Thanks Dan,
You’re right; it is senseless to float.

I don’t seem to have much of a moisture problem, however would still like to raise the floor… just to be on the safe side.

I’m still not too clear about the sand technique.
Is it basically a 2x4 frame filled with sand with regular floor layers on top of it?
Is there a picture or link to how it is actually constructed?

Raising the floor won't cure a moisture problem. water travels upwards quite easily due to capillary action. Especially in sand

If you're worried about moisture you should simply put down a Damp Proof Membrane ( thick plastic sheet ) OR seal the concrete with a water proof sealent.

Much cheaper and easier than messing around with pointless raised floors


Paul

Thanks Paul,
It seems like my FLOOR issue is getting simpler and simpler.
My next question is:
How do I layer hardwood flooring over Vapor Barrier?

Dan Fitzpatrick wrote:hi alex, fellow bay area dude,

Yeah, fellow Northern California dude -- you (AlexT) need to join us!

i'm at the exact same point as you, trying to figure out whether to leave the slab bare or somehow floor over it with some additional layer, perhaps a thin sand layer (i've pretty much decided not to float).

Dan! So you're abandoning the idea of floating, eh? But, but, you're my hero!

haha hi keith ...

getting me back for when i said that to you ... that was back when i thought floating was always a good thing ... now i've learned that it's a lot more complicated

no i'm not floating, for reasons i'm sure you've been following. if you have any disagreement to that decision, i'd love to hear it

i have a comment to add about your situation, but i'll stick that in your thread a bit later.

dan

sharward wrote:Alex you need to join us

Just did Kieth

Dan! So you're abandoning the idea of floating, eh?

I agree with Dan, seems like floating a small studio is more of a risk than an advantage.

Anyhow, my next question to Steve, Paul and all you other wizards is:
How do I layer hardwood flooring over Vapor Barrier/Damp Proof Membrane... since gluing is not an option on a plastic sheet?
Would using one of those Home Depot foam/plastic hardwood-floor underlayments work for acoustical purposes?
I'm just worried since nothing is glued straight to the floor?
Alex