heavy duty rubber tiles for the studio floor

[tomaskarkalas]

i just took an industrial unit where i started building a recording studio at the back. Concrete slab seems to be repaired some time ago (new layer poured over), and in has couple of cracks. Also in couple of places sounds like it's hollow, possibly the top layer didn't stick to the old slab.
My concern is resonance and sound leaking between the rooms through imperfect floor.
Taking the top layer out is not an option, as the total area is quite large. Pouring another layer on top seems like massive job and not sure if it would solve the problem?
I got offered a lot of 50mm heavy duty gym tiles at a discounted price (works out round £16/Sq m). Picture attached.

Some technical data:
38kg/Sq M.
Surface density 780kg/m3
Tensile strength ≥0.3Mpa
Elongation at break ≥40%
Compressive deformation ≤15%
Resilience ≥38 %
Flame resistance 1 grade
Water permeability ≥40%
Hot-air aging 70℃*96h
Rate tensile strength ≤20%
Rate elongation at break ≤20%

any ideas if using these tiles under the laminate flooring would solve the problem?
any help appreciated!

[Soundman2020]

Hi. Please read the forum rules for posting (click here). You seem to be missing a couple of things!

- Stuart -

[tomaskarkalas]

sorry Stuart, should have forum read rules first.. to impatient

All is happening in London, UK.

Control room is 3m x 4.5m and 2.9m high ; Live room 7m x 4.5m and 2.9m high. These are rooms inside the room. 2x4 studwork, 100mm RWA45 rockwool, three layers of 15mm Soundbloc plasterboard and Green Glue sandwiched between first two layers (two tubes per sheet).

There's no neighbours realy that i should be worried about, it is more to isolate two rooms from each other.

Budget - up to £1000, time is also of an issue.

[Soundman2020]

My concern is resonance and sound leaking between the rooms through imperfect floor.

Is this a slab on grade, or is there some type of air space under your slab?

Pouring another layer on top seems like massive job and not sure if it would solve the problem?

Well, it probably would solve the problem, but not for £1 k. Also, I'm not even convinced that you do have a problem.

Some technical data:
38kg/Sq M.
Surface density 780kg/m3
Tensile strength ≥0.3Mpa
Elongation at break ≥40%
Compressive deformation ≤15%
Resilience ≥38 %

That's the acoustically useful stuff, but it's incomplete, and very questionable. For example it says that resilience is 38%, but resilience is not measured in percentage point! Resilience is measured in joules per cubic meter (the amount of energy that can be stored in the material, elastically) .... so units of "%" are not a lot of use, and don't even make sense. It doesn't even say what type of rubber it is! Natural/ Synthetic? Neoprene? EPDM? Sorbothane? Something else? All of those have very different properties, and floating a floor is a rather delicate thing to attemp.

50mm heavy duty gym tiles

To be very honest, I don't see those as being very useful for what you want. Unless you have actual acoustic laboratory test reports showing how this specific material behaves when used in the way you plan to use it, you are on your own. It may not even be legal to use those under flooring: check your local building code.

any ideas if using these tiles under the laminate flooring would solve the problem?

It would create another problem! Your floor will crack, and will not be covered by warranty. The manufacturers of laminate flooring are very careful to specify exactly how flat a surface must be before you can use their product on top, and they are just as careful to specify exctly what type of laminate floor underlay can be used, and what the acceptable thickness range is. Usually, that's something like 2mm - 5mm thick. If you use underlay that is NOT approved by them, then your floor will probably crack, and they will b under no obligation to fix it or replace it.

I would suggest using just ordinary, approve laminate underlay, and a good thick laminate flooring product.

- Stuart -

[tomaskarkalas]

Soundman2020 thank you for your help!

My concern is resonance and sound leaking between the rooms through imperfect floor.

Is this a slab on grade, or is there some type of air space under your slab?

it is slab on grade. but when you drill or knock on it you can hear that it has two layers and a gap in the middle.

Pouring another layer on top seems like massive job and not sure if it would solve the problem?

Well, it probably would solve the problem, but not for £1 k. Also, I'm not even convinced that you do have a problem.

There are few big cracks where the slab moves a little when you step on it. I might be totaly wrong but i imagine if there are gaps in the slab, the sound might travel through it. Also the thin top layer of concrete could transmit the sound because it has way less mass than thick original concrete slab. Please tell me im wrong on this

Some technical data:
38kg/Sq M.
Surface density 780kg/m3
Tensile strength ≥0.3Mpa
Elongation at break ≥40%
Compressive deformation ≤15%
Resilience ≥38 %

That's the acoustically useful stuff, but it's incomplete, and very questionable. For example it says that resilience is 38%, but resilience is not measured in percentage point! Resilience is measured in joules per cubic meter (the amount of energy that can be stored in the material, elastically) .... so units of "%" are not a lot of use, and don't even make sense. It doesn't even say what type of rubber it is! Natural/ Synthetic? Neoprene? EPDM? Sorbothane? Something else? All of those have very different properties, and floating a floor is a rather delicate thing to attemp.

It is EPDM rubber. And this is the only technical data i've been given, sorry

[Soundman2020]

(new layer poured over), and in has couple of cracks. Also in couple of places sounds like it's hollow, possibly the top layer didn't stick to the old slab. - when you drill or knock on it you can hear that it has two layers and a gap in the middle.

That's rather strange for an industrial unit. I'm trying to understand why there's a "disconnected" additional layer of concrete on top, and wondering if this was maybe an attempt to "float" the floor. IS there any way you can find out how that extra layer was put on, how thick it is, and if there's anything between it and the base layer? If it really is a floated slab, then that might not be a bad thing.... provided that it was done correctly.

Maybe you could provide some photos of the slab?

- Stuart -