Concrete block walls on heavy timber floor?

[pwsharp]

I have at my disposal (for no cost) sufficient 35mm particle board (ex office panelling) hopefully to use as flooring for my intended studio. The studio will be in a detached garage on a concrete slab. My question is, being much heavier than the usual timber flooring, is there a suitable method of under-floor support for a wooden floating floor with hollow concrete blocks as the wall? I envisage bearers (75x125mm) around the edge to support the concrete block walls - which would sit on top of the 35mm particle board - while joists (perhaps 50x150mm trimmed to 50x125mm) would suffice for the rest of the open floor, with rockwool in the cavities. What type of mounts would be required? If spring mounts under the walls/bearers, would neoprene still be adequate for the open floor areas?

Thanks, Peter.

[pwsharp]

On another thread I've also heard mention of Hebel blocks. Could hebel also be a possibility? Are they (or could they be) hollow also? I know Hebel is much lighter / lower density than concrete, so perhaps not as effective an insulator. Are there sound-proofing ratings available for Hebel products?

BTW, my situation is an acre block on the edge of town & edge of bush. Nearest neighbouring dwellings are 30m & 100m from the proposed studio, with my own home 5m away. Intended use of the studio (initially at least) will be rehearsals, lessons & as a practice venue for local bands. Recording will come later & I am planning with that in mind, too. So, the main need for sound-proofing is to provide sound insulation for my own home & occupants.

Peter.

[John Sayers]

Hi Peter -welcome to the site:)

Mate I wouldn't worry about floating floors in your situation. Your neighbours aren't going to hear the 30hz in the drummers kick out where you live.

Use the particle board as wall lining instead of drywall.

cheers
john

[pwsharp]

Thanks John. I initially thought of the walls - but I only have enought of the particle board for about half my walls. Still wondering if this as flooring could work with a masonry (hollow block) wall. And I don't want anything to be heard inside my home (light sleepers - you know!).

Peter.

[knightfly]

Peter, even for isolation from your own home a floated floor would most likely be a waste of time and material - the only exception to that would be if both your home and the detached garage are sitting on solid bedrock. Otherwise, if 5 meters of earth isn't enough to deaden the low frequency from your studio then you should learn to play quieter, or your ears won't last more than a few hours.

You didn't list dimensions (all three) of the inside of your space, so this may need modification - what I would do is to make sure that all walls and the ceiling adhere to the principle of 2 leaf, one air space - where you have two centers of heavy mass (including the outside wall) with one air gap that is dampened with cavity insulation - if you have the space, you could put the INNER leaf on its own separate frame. Read through some of the wall construction threads here, I've repeated myself to death on this. The secret is two, and ONLY two, leaves in a wall (a leaf can be any number of LAYERS, as long as they have no air gap between them), separated by one air gap (insulation is considered air, only better) and the wider the air gap the better the isolation. The more mass in the leaves, the better the isolation. Using different thicknesses of paneling in each leaf helps, as does different construction for inner and outer leaf.

If you do your walls and ceiling correctly, and SEAL EVERYTHING, you should get really good isolation from the house. Then, if it's STILL not enough, you can build your floating floor INSIDE the inner walls. We can help with that part too, but first please read the EXISTING threads on floating floors - some of your questions may get answered there.

Following this sequence could save you having to over-build, that's why I suggested it... Steve