Very important question, what would you do?

[jeronimo]

Ok, I was planning to build my homestudio, I already have a room with standard bricks (not concrete bricks). Those are not solid bricks, they're 'hollow' inside. I thought about building another room inside this room with the same kind of bricks, 2" btw the walls. Those 2" would be filled with rockwool or fiberglass. Someone told me I should not build the inner walls with bricks, he told me I should use plywood (just like the projects in the SAE website) with rockwool instead... he told me it will be more efficient 'soundproofwise'.
What do you guys think? John? Everybody? HEEEELP!!! I really don't know what to do... I already bought the bricks, but I could exchange it for something else that I'll need... Heeeeelp!!

[Garak]

Bricks seem like alot of work to me. Drywall/plasterboard/gyprock/sheetrock/whatever you want to call it is likely to be cheeper and easier to work with. Thats the sheeting material used on everything on sae.

[ausrock]

jeronimo,

I would be hesitant to put anything between the brick walls because of the possibility of moisture build-up..........I imagine you could build the second/inner wall as planned, maybe increase the gap tp the outer wall a little, then still line the inside with sheeting. If you attached 50x50mm battens to the inner brick surface it leaves you with space for rockwool between the ply and bricks.
THE ABOVE IS JUST A SUGGESTION!!!!

John is travelling home at the moment and I presume may be at least a couple of days before we see him here again.

[kristian]

I think the outter wall bricks like you suggest are fine. Leave the 2" space with air, then do the usual 12 or 16 inch stud placement with insulation on the walls and roof, then sheetrock, wood, rockwool, or any other choice for walls. I think you will find acoustic using sheetrock or wood will be favourable compared to an inner wall of brick.

[longsoughtfor]

jeronimo - Most brick walls are more then one brick thick. It seems like building another brick wall is both a bigger space consumer and more expensive... One brick wall is great! Save your energy and resources and build a traditional wall on the inside.

One other thing is that the traditional wall will be easier to build acoustic control into... an inner brick wall would be very live.

Cheers
Kevin.

[ausrock]

kristian and longsoughtfor,

I agree with what you are saying about traditional stud frame inner walls, however I was anticipating that returning the bricks may not be a viable option.
Maybe I didn't make myself clear, but my comments were based on the fact that bricks had already been purchased for the inner wall.
What I was suggesting was that jeronimo go ahead and build that inner brick wall, then line it with sheetrock, plywood, etc.

[jeronimo]

So you guys think the second brick wall won't be efficient as a stud/plywood/rockwool wall to handle SPL? Damn... I'll try to see if I can return those bricks... the problem about the brick wall beign 'live' don't bother me, that's what I'm going for... I'll try to control it later with bass traps and some rockwool on the walls...

[longsoughtfor]

My bad Jeronimo - Ausrock, I had not seen the part about already having bought the bricks.

Jeronimo, do what makes best economic sense for you. Plus what make you most happy to be in your studio!

Kevin.

[kristian]

Plywood/rockwool etc. are still live materials. They just don't have the super reflective tendencies that bricks do.

[jeronimo]

Hey Kevin, I'll be happy while I'm inside my studio, doesn't matter what kind of walls it has !!!!
My question I just about handling high SPL!!!! Would bricks be as good as the regular SAE projects? Worst? Better?

[jeronimo]

Is that all??

[longsoughtfor]

Jeronimo - I think the SAE site has an STC chart with both brick and standard wall's included. You can compare the differences there.

Good luck! Keep us up to date.
Kevin.

[jeronimo]

I was looking at the STC chart and I have a question... If I have double walls the coeficients double?

[ausrock]

I think from memory, that the higher the number, the better the effectiveness of a given product.

If it was me in your position, considering I would already have the necessary bricks.........I would continue as planned to build the inner brick wall with a minimum 50mm air gap between inner and outer walls.
Then check the amount of noise reaching the outside. Construct corner bass traps and make some temporarily moveable wall units ( see other thread on Wall Units) and start tuning the room.

Only use sheetrock, plywood, etc as needed ONCE you have tested the bare brick room, with or without basstraps, etc..........don't spend any money until you are sure you have too.

[jeronimo]

Hey ausrock, that was exactly what I was thinking .
By the way, I found some places that sell rockwool and fiberglass. Even with the moisture problem, do you think adding fiberglass/rockwool will help to keep the sound inside the room (ausrock, I didn't understand your comment very well, about the plywood/rockwool thing in your first post :/).
And, double walls have twice the STC? Yes or no?
Well, tuesday I'll have people starting the construction, I'll keep you guys posted about that.
I'm worried about the SPL outside the room because I'm a drummer, and I want to be able to play any time, day or night, and the studio will be very close to the my kitchen and close to the bedroom... let's see how happy I'll be!

[ausrock]

OK, it's easier for me to explain this verbally rather than drawing and posting diagrms. This is how I personally would be approaching the job, if John were here, he may advise a bit differently.

Working from the outside you have:

1; An existing brick wall
2; An air gap. (With nothing filling the void)
3; A new brick wall. (It may be wise to paint some masonary sealer on the bricks once everything has cured)

Now at this point, I would play drums, make lots of noise in the studio while checking how much is audible outside..........if the levels outside are acceptable, then great, just treat the inner walls enough to control standing waves and reverb type issues. HOWEVER, if the outside noise levels are still too high, then I would continue to fully line the inside brick surface. Continuing from above..........

4; Resilient Channel or timber battens (attached to inner brick surface)
5; Rockwool
6; Sheetrock/Plywood/MDF (attached to Res Channel or battens)...........this would be your final inner surface.

The heavier/denser this inner lining is, the better it's ability to absorb and not transmit vibrations. Hopefully the rockwool behind it will minimise the effect of that sound transmission.
ALSO, seal ALL joins and gaps.....the room must be virtually airtight to be effective where sound leakage is concerned.

Hope this makes sense.

[jeronimo]

Great ausrock, that is what I'll do!! I'll keep you guys posted... by the way, do you think John would put my "project" at the website? That would be cool, 'cause everybody is helping me so much, than I could leave some feedback with my experiences... I don't know !

[ausrock]

Take photos as it comes together and ask John when he re-surfaces here. I would imagine it wont be a problem.

Good Luck.........

[jeronimo]

Where did John go?

[ausrock]

He was "in transit" around the countryside but is back now

[barefoot]

jeronimo,

Soundproofing is certainly important and probably done much more easily with wood construction. But if you plan on recording live acoustic instruments the sound character of the room can also be very important.

If you have some good bricklaying skills, you could wind up with quite a unique and pleasing acoustic environment. You'll sacrifice space, but curving the walls, and especially curving the corners can make for a beautiful sounding room. You could also create a texture in the wall by staggering the brick faces. There are lots of creative things you might do.

Maybe you're not looking to build an "acoustic space", but it's something to consider.

barefoot

[jeronimo]

barefoot, thank you very much for your reply... I'll experiment for sure!!!
ausrock, thanks again!

[John Sayers]

I'm back - I think? no sooner did I get back and my phone line went out, (water in the line) and since our Gov decided to privatise our phone system we have cheaper phone calls but no service

What Ausrock suggested is correct IMHO.

This is great - when I started posting here 2 years ago noone seemed to know anything about acoustics but that's finally changing

very happy to post your construction jeronimo - send me the pics with some related text

cheers
john

[ausrock]

John,

Water in the lines makes it virtually impossible to work, due to safety issues..........the line techs apparently have to wait till things have dried out somewhat. This is according to my wife who is now working in Telstra's Corporate Call Centre.....I think if you have 3 or more lines you can qualify as a corporate customer, then you could ring my wife and hassle her.......lol.

Any advice (hopefully valid) I give on studio design is mainly due to what I have learnt from your tutorials and input........again many thanks


ChrisO

[John Sayers]

All fixed now - I'm not with telstra which is probably the problem. Give me her number and I'll hassle her anyway

cheers
john