Home Studio Build

Hello again, I've started a new thread here, because my previous one was in the design forum and construction is now well under way. Here's the background: http://www.johnlsayers.com/phpBB2/viewtopic.php?t=5765

So the builders knocked everything out apart from the chimney breast which will be removed next week. The floor in the old bathroom was dug up. 60mm of sand went down, then a polythene membrane, then 50mm of polystyrene, then 100mm concrete. The concrete is drying over night and then I must decided how to lay the floor and walls onto it.

Awesome man! That's going to be really cool. I can't wait to see more pictures.

Thanks. I really need to get some advice about this floor, so that I can order the neoprene to arrive Monday A.M. I found a company in the U.K called Christie Grey - they've had some big clients and designed some decent products for room-within-room studios, i.e, Resilient Sway Brackets (which I've discovered in the UK are called Resilient Wall Ties), and neoprene / rubber / anti-vibration products like this: http://www.christiegrey.com/studflex.html Anyway, what I'd really like to know is which of the two floor plan options you prefer. There is a real issue with head height and I can't afford to give up too much. I think I know which you will say you prefer, but is there really that much difference if my air space in option 2 is only 25mm? Any feedback very very welcome. Thanks

If you go with option 2, you will be introducing a resonant space into your floor (think about a giant drum head), that may cause you a headache. the space of 25mm just determines the frequency of the drum head. it will just be a higher frequency. Why do you need any neoprene at all? you already have a slab that is isolated from the building, why not just build on that? the neoprene is not going to make that any better IMHO. it won't make it better, and it will possibly make it much worse. also you should not need neoprene under your walls, just build right on the slab. again IMHO ... save your money. If you are really worried about having excellent isolation, you are better off giving your walls a larger airspace and adding another layer of plasterboard there (although your brick is a definite plus here). by the way, what are you planning for the inner and outer ceiling? Dan

Just to put in my two cents worth, you sound like you're going to immediatly start building on your new floor. Everything I've read here and other places say you need to let the cement cure for AT LEAST a couple of weeks before you can start building on it. It takes time to build up strength. Find out from your concrete vendor how long you should wait before putting any kind of load (other than walking) on it. len

Thanks for the tip - they haven't built on it yet and it probably won't be for at least another week now. I will ask my supplier how long I should wait. Today was a real struggle. Its difficult enough trying to convey the room within a room idea to anyone, let alone builders who speak very little English. To fair though, these Polish guys are superb - they work very hard and they don't mess around. I think the chimney breast is being removed next week; the people in the apartment above me have decided to remove theirs also, so the builders will start at the top and work down. I would imagine it will be Thursday or Friday by the time its gone. In the meantime I need to get working on my plans because it doesn't even really seem clear to me yet how this is all supposed to piece together. I'll post some more plans asap. Cheers, Trevor

If you want to get the idea of "room-within-a-room" across, try explaining as building a self standing outhouse in the middle of your room, just expanded out to right up close to the existing walls/ceiling. len

Dan Fitzpatrick wrote:

Why do you need any neoprene at all? you already have a slab that is isolated from the building, why not just build on that? the neoprene is not going to make that any better IMHO. it won't make it better, and it will possibly make it much worse. also you should not need neoprene under your walls, just build right on the slab. again IMHO ... save your money.

I thought the timber frame of my drywalls were best off being built onto a material that would prevent the vibrations reaching the floor and in turn the outer walls. The other half of the studio has a timber floor, made from joists which are attached to the wall, so I think I will definately need to figure out a way to prevent the impact noise travelling through to outer walls in that room.

by the way, what are you planning for the inner and outer ceiling?

I will post the details of my ceiling design asap. The outer leaf is the floorboards and the joists which hold up the apartment above me. I have removed the plasterboard that was attached to those joists, and new joists will sit on my drywall timber frame. These new joists will protrude an inch or so lower than the old ones and will hold the new plasterboard ceiling. Bye for now. :?

Temas wrote:

These new joists will protrude an inch or so lower than the old ones and will hold the new plasterboard ceiling.

Nice! That'll work out great for decoupling from the stuff above you. If you can afford even a little more space you'd gain even more.

Hi Temas, I just said what i said based on those two sketches. If you are building on a slab that is isolated, you don't need the neoprene. But if there are other parts where you are building on existing house's wood floor, then that's another story. Maybe neoprene could help here. But, let me just throw an idea out there, which may be crazy ... I wonder whether the best thing on the part that is wooden is to build an isolated floor that is supported by the earth below, without touching the existing structure. basically tearing out the subfloor and buildign a new floor on pillars. but that is just an idea, i've never heard of it done. I just mention it because you look like you are going for big time isolation, so building on an existing wooden floor might be somethign to avoid if you can. The wood floor won't be designed to support the weight of your inner leaf anyway. Seriously, it might just collapse if you overload it with a 10,000 pound inner shell ... Dan

This was my ceiling plan, but the underneath of the floorboard are so covered in pipes and wires that it is impossible to lay the plasterboard up against the underside of the floorboards. I've managed to lay some soundbarrier mats flat against the floorboards but I don't know what else I can do to add more mass to that leaf.

Dan Fitzpatrick wrote:

Hi Temas, But, let me just throw an idea out there, which may be crazy ... I wonder whether the best thing on the part that is wooden is to build an isolated floor that is supported by the earth below, without touching the existing structure. basically tearing out the subfloor and buildign a new floor on pillars. but that is just an idea, i've never heard of it done.

I have thought of this also, but not in great detail because I think I'm a little scared of what I might be getting myself into. The cavity beneath the joists appears to be only about 2 foot, so I think it would be possible. I'll try and post some detailed pictures. There is a also a small cellar (20' x 6') under part of the apartment with 5 foot high ceilings, which I would like to excavate further, but just as and extra storage area.

The wood floor won't be designed to support the weight of your inner leaf anyway. Seriously, it might just collapse if you overload it with a 10,000 pound inner shell ...

Man, I need to consult another structural enigeer - I've got 75 sheets of soundbloc sitting in a pile in that room. I just did a sum and it totals over 7000 kilos (not sure what that is in pounds).

well yeah that's over 15,000 pounds. over 7 tons. if that's one stack of 4x8 sheets then that's 480 pounds per square foot. normal loads for residential contruction is more like 50 pounds psf. :shock: so yeah, that would worry me. be careful ... collapses can happen without any warning. so one sheet of sound block weighs 93kilos/205 pounds? about 3 times what a sheet of firecode drywall weighs. that's impressive ... anyway, don't go under there. :o

Sorry, big mistake. Its approx 2721 kg. So thats about 6000 pounds I guess. Pheeewww!!! But thats still a lot. :oops:

That's kind of what i suspected. I think you would have noticed a hole in your floor by now, with a bunch of sound bloc at the bottom. :) So 187 lbs/sq.ft, still way above what the average home in the US is designed to support ... at least current US standard ... in any case, you need to look into it and see what the floor can support. i'm sure by the time you are done you will have a lot of other heavy things to add into the equation ... building on top of your existing floor may not be an option. also from an acoustic perspective, floating a wooden floor on top of another wooden floor is just something to be avoided. unless you can afford an 18 inch airgap with about 5 or 6 layers of plywod or gypsum etc. mass in the floor. which again, you can't do because of the weight. you will quite possibly get a floor that "rings" at a certaiin hz.