I just take this pictures...
The first one is the floor i´m planning to float... a tipical terrace floor in Argentina... (the thing is that the floor is a little angled, so, i also want to float the floor to correct it)
Te second picture is where the new window will be put... bigger and wider!
On the last one you can see where the new wall will be constructed... Te room showned is the control room, so the new wall will make the recording room...
What do you think? See any problems?
Thanks!
Depends; are those tiles that are the terrace floor resting ON THE GROUND, or on concrete, or are they on an elevated floor? How thick are the tiles?
Your architect said not too heavy on the walls; this tells me that there may be a problem with too much weight on the REST of the terrace floor, so I need more info to be sure... Steve
Steve... i don´t know if i used wrong the term "terrace"... That´s the second floor of my house... i mean, above the GROUND it´s the whole house, and above the house you have this terrace... By now, i can´t really tell you how thick are the tiles.. i´ll try to figure it out...
So, you can say that under that floor, you have my sisters bedroom ceiling...
The architect told me that´s not a good idea to overload the terrace floor, because this may cause the ceiling that is under start to crack. So she suggested to use hollow bricks, but didn´t said that anything about the floating floor... Her advice was to try to reduce as much as i can the weight of my new construction to avoid typical overload problems...
So, yes, the idea of not put much weight is for all the construction, no just the walls...
Wow, this just PROVES I need to get out more... Besides, probably a few hundred of those were just "fluff", so they don't count...
Just as I suspected on where your studio will be; now, can you (or your architect) do some sort of sketch showing the various layers between your sister's ceiling and your studio area's floor, including thickness and shape of framing, spacing between frame members, type/thickness of floor materials, etc?
Also, is gypsum wallboard available in your area and if so, how expensive?
I think your architect is trying to save your sister's life here; I'd recommend you listen carefully... Steve
I´ll try to post the sketch this afternoon... stay tuned...
And, yes, gypsum is available here, and it´s not expensive... in fact, i´m planning to use 2 layers of gypsum as my inner mass...
Why you asked me that?
I asked you that because gypsum is a good mass layer anywhere except outer surfaces, and can allow lighter WEIGHT partitions with as good isolation, if the extra space that would have been taken up with hollow blocks is instead left as air/insulation space - remember, it's mass-air-mass, so the more "air" between the better. This can compensate for lack of mass somewhat, keeping your construction lighter but still good for isolation... Steve
So, do you think that this it´s the best possible layout ?
I will only render the wall on the outside, and create a 20 cm air gap... (i can´t make it bigger, my room is not that big)
The gypsum boards are 15mm thick.
By now i´ll only use 2 layers, ´cause i don´t have all the money, but if i really need it (after seeing what happens with 2 layers) i would put the 3rd one.
Any other suggestion?
THAnKS!
What I'm talking about is to NOT use the hollow blocks (or are they already in place??) but instead use something lighter WEIGHT that would eliminate the extra "leaf" of the hollow blocks, and at the same time INCREASE the air gap to compensate for the loss of mass - something like a stud frame with about 30mm of MDF plus a layer of weather proof siding outside, these mounted on a normal wood stud frame; then your inner frame with gypsum, and fill between frames with insulation.
This would save weight, get rid of the third leaf, and give better low frequency isolation while keeping mids and highs as good as your drawing would do... Steve
I like the idea! By using that system i can achieve a 300 mm air gap!
The thing is, high density fiberglass is a little expensive here... so, do you think that i can use 50kg/m3 wool on the inner frame, and a 13kg/m3 on the outer... It´s critical on this kind of design?
A mix of heavy and "normal" insulation will work fine; do you have anything in mind to use for your outermost layer on the outside wall? Gypsum won't work for that layer, it needs to be more weatherproof... Steve
For the outer layer i´m planning to use 18mm gypsum board and attached to it, a layer of wood (similar to pine) treated to be weatherproofed...
That´s the idea i came up to have the mass of the gypsum and the weatherproof capacity of wood... what do you think?
Yes, since the studio will be exposed to weather changes, i´m planning to use a vapour barrier... right now i´m searching different brands here in Argentina, so i can ask you if i don´t understand anything...
BTW, where should i put the vapour barrier? In which frame -inner or outer-?
Steve, before getting into the vapour thing...
I found this... http://www.usg.com/USG_Marketing_Conten ... 63-003.pdf
from USG...
The seller told me that i can use it with basecoat and it´s 100% weatherproof. Do you think it´s a good material for the outer layer?
I´m planning to use 50kg/m3 mineral wool on the frame...
Besides, probably a few hundred of those were just "fluff", so they don't count... 
that would eliminate the extra "leaf" of the hollow blocks, and at the same time INCREASE the air gap to compensate for the loss of mass - something like a stud frame with about 30mm of MDF plus a layer of weather proof siding outside, these mounted on a normal wood stud frame; then your inner frame with gypsum, and fill between frames with insulation.