In the last pic the wall will be where you have signed the orange line...
Good, but you will also need to decouple the other two walls form the concrete block wall behind. If you leave that framing as it is, you will not get isolation, as you will still have major flanking paths. The same applies to decoupling ALL of your walls from the concrete ceiling above: unless you do that, you will have poor isolation, due to the flanking.
The window are made in 2 separate walls and the rounding wood that you see will not touch the other rounding wood that will be mounted on the other wall
That's not what this photo shows:
Coupled-walls-04b.jpg
Clearly, the wood goes all the way through and contacts both walls. There is no way that such thin wood can support the weight of both windows if it does not rest on both frames.
And regardless of that, even if you could keep it from touching, you are still destroying your isolation because you do not have the necessary gap between the frames for installing the necessary deep porous absorbers around the edges of the frame. Without that, you have no acoustic damping in the cavity, which has a major effect on both the MSM resonance and the coincidence dip. Take the equation that you used to calculate the MSM resonance, and change the constant from 43 to 60, and you will see what I mean. 43 is for damped cavity, 60 is for undamped. Actually, you should probably use something more like 70, since you are also sealing the cavity edges with substantial rigid mass.
the grey that you see is the concrete with no floor
OK, but that makes no difference: there is still no benefit to that, and it is only wasting room height. If you leave that out, you would have several extra centimeters of height in your room, which is very important for such small rooms.
What is the original floor made of, under the concrete that you added on top?
I will use a bamboo wood that will be glued
Do not glue it! Instead, use a thin acoustic underlay, and just put it on top of that, which is the way laminated flooring is supposed to be installed.
It seems to me that there are a lot of problems with the concepts behind what you are doing, and I would urge you to stop and fix all off those before you proceed. There are several mistakes, and they can all be corrected at this stage, but it will be difficult and expensive to correct them later. If you don't correct them, you will end up with poor isolation for low frequencies.
- Stuart -
