Trying to make a low ceiling as invisible as possible

Hi trying to iron out as many of the kinks in my space as possible and could use some advice. My space is slightly oddly shapped, ok it's odd as you'll see with the sketchup I've included. I am fully aware that the size of the room and shape are going to make my job an uphill battle, but I'm working with the space I have. The room is for practice and recording my own stuff, occasionally friends music as well. I don't plan to do any mixing as such in the room, for the moment I'll be doing rough mixes using headphones and leaving it at that (I'll pay for someone else to mix in a real room if it seems appropriate). So the problem I am trying to sort out at the moment is the low ceiling, lets be honest the really low ceiling - approximately 2.2m to the base of the beams supporting the floor above. I am looking to try and minimize sound transfer to my house upstairs and if possible make to ceiling itself kind of 'invisible' acoustically, essentially convonce my ears and mikes etc that it isn't as low as it is. Is there any way this would be possible, within the bounds of the broke student/ basic home handyman arena? The Floor above is timber, the beams are 110mm deep by 450mm appart. The rest of the construction of the room is cement floor, timber stud walls with an outer skin of fibro-cement sheeting, stuffed with pinkbat insulation of the highest rating I could find (3.5 I think) and an inner skin of as yet unpainted MDF approximately 5-7 mm thick. Unfortuneately I can't do anything about the posts in the room as it would be a major job to restump the house and is obviously outside my studio budget. I don't have a fixed budget and I'm willing toi slowly work away at the problem as the money becomes available. I hope I covered everything you need for this if not let me know and I'll edit this to add the details or post extra as requested. Thanks for all the great info here on the site. Hope to hear back from one of the great luminaries on this site, if necessary I can also provide pics of the room or ceiling or whatever will help, Thanks, Nate

Hey there Nate. Welcome! With such a low ceiling, and since you also need some isolation for the room above, I reckon your best bet is to build an "inside-out" inner leaf ceiling, and fill it deeply with mineral wool or fiberglass insulation. So, if it were my room, I think what I'd do is first beef up the underside of that floor above you, using 5/8" drywall (16mm plasterboard) cut to fit exactly between the existing joists, held in place with cleats, and caulked all around the edges carefully. If you have loud instruments (EG, drums) then you'll need at least two layers of drywall up there, and more if you can afford AND I>F THE STRUCTURE CAN TAKE IT! This is an extremely important point, often overlooked: Get a structural engineer to check that floor and make sure it can handle any extra load that you plan to add to it. OK, so now you have your floor beefed up and sealed, but you are still going to have major "leakage" around that ceiling, due to the sound "flanking" through the walls, which are directly coupled to the rest of the building. To deal with that, you need to remove that "inner skin of as yet unpainted MDF approximately 5-7 mm thick", beef up the "outer skin of fibro-cement sheeting" in the same way as you did for the floor above you (a couple of layers of 5/8 drywall fitted between the studs), then build a second timber stud frame, an inch or so away from the existing frame but not touching it anywhere, and put a couple of layers of 5/8 drywall on only ONE side of that frame. Fill the gap between the two leaves with fiberglass or mineral wool insulation. So now you have the basic structure isolated and decoupled: Now you can get to your real problem: the ceiling. Here, you need to build that "inside-out" ceiling that I was talking about. This ceiling will consist of joists across the new inner-leaf frame that you just built, with drywall on the joists. "Inside-out" means that instead of putting the drywall underneath the joists like you normally would, you put it on TOP of the joists. This obviously complicates construction, but it does gain you 9cm of room height for your ceiling treatment: the space between the joists. The hassle is that you have to build the ceiling in sections, on the floor, with the drywall on top of it, then lift each section into place, nail/screw/bolt it in place, and seal it. You need to calculate the height just right do that the drywall ends up just below the existing joists of the floor above, like maybe 4 or 5 cm away, and you have to fill that gap between the floor above and the new ceiling, with mineral wool or fiberglass insulation. So now you have your total room height just a few cm shorter than it was originally, but well isolated and with all that space between the new ceiling joists for your "disappearing ceiling" trick. You can't make it disappear completely of course, but you can minimize it by installing stacks of mineral wool or fiberglass up there, between the joists. Fill the entire gap, and then cover it with acoustic cloth or something like that to hide the "ugly". Here are the numbers: You say you have 220 cm to work with from the bottom of the existing joists. If you leave a 4cm gap below that to the top of the drywall, that leaves 216 cm. 2 layers of 5/8 drywall takes up another 3.2 cm. Call it 4, to allow for imprecision and Murphy, so you now have 212 cm at the bottom of the drywall, which is the final acoustic height of your room. Assuming you used 2x5 joists, you can get a depth of roughly 12cm of insulation across your entire ceiling, and the bottom of the new joists will be at almost exactly 2m above the floor. Which is VERY low, of course (you already knew that! :) ), but still usable, I think. And those 12cm of insulation up there should help considerably to make your ceiling sound higher than it is. You can also build those new inner-leaf side walls "inside-out" if you want to: that will give you extra sideways space in the room. - Stuart -

Thanks Stuart, guess I'll start buying up as much plasterboard as I can afford, might look into shares in the company :lol: Thanks a lot for the reply I'll be taking a while to do this as my budget is low on a week to week basis but essentially unlimited - wife permitting obviously. Will post once something meaningful has happened I guess. Thanks again to the group for all the great info and help on the board, Nate

might look into shares in the company

And buy some shares in a mineral wool or fiberglass insulation company, too! Also in an acoustic caulking company, a timber company, an air conditioning company, a .... :) Jokes aside, how about if you post some pics of what you have, to give folks a better idea? Pics always help to spot potential "gotcha's" in advance. Plus, as they say here: "No pics means it didn't happen". - Stuart -

Ask and you shall recieve - and possibly regret it later :lol: Ok here is the sorry state of things at present, if you want more details about anything or better shots of anything particular let me know. Sorry about the dark photo's, can't seem to locate my external flash at present :roll: Nate

Well it's been a while since I posted and things are moving on. I have replaced the window plugs, things are quieter and the sound of the room has actually improved a bit (audibly, I don't have testing gear ... yet) Anyway on Friday afternoon I had a friend of a friend who is an engineer come and check the place out - not so good sadly. Basically I explained the situation to him and what I was trying to do including pics etc from here and other places and the result as far as he was concerned was it is a no-go too much weight for the structure to cope with, apparently way too dangerous. Bugger! So moving on is there some way i could seal the floor above with a paint type substance (I thought about soundproofing bitumen like they use in cars but I'm pretty sure that that's flammable and in a 60 plus year old timber building I don't want to tempt fate) to deaden footfall noise etc from upstairs. Is there anything like this available, are there simpler and lighter options? My current idea would be a thick coat of undercoat to seal all the small gaps between the floorboards then as much rockwool or equivalent as I can jam in there then a ceiling sealed as well as possible and clouds or similar absorbers spread around to reduce reflections etc. I will post some photo's of my new window 'plugs' (basically large absorbers with 20cm deep insulation in a timber frame hung over the blocked windows. I really appreciate any help that you guys can provide and thanks for the comments so far, Nate

Nate - if it were my room I'd fill the space between the ceiling joists with rockwool and then I'd line the ceiling with plastic and shade cloth from the garden shop. It looks like this ceiling in Lovestreet when finished You'll experience a notable difference.

Thanks a lot for the reply John. I'll do that, I'll still give the thick coat of paint a go just to help seal the floor boards a bit better than they are at present. I have started collecting the timber, rockwool etc to bulk up the walls so hope to be making larger/ more obvious improvements. Will post a few photo's of the changes as they occur. Nate

Thanks again to everyone who's weighed in with advice on my build, as low tech and low end as it is :roll: Here are a few pics of the latest addition to the room, some over engineered window cover/plugs/ absorbers. They are made with a pine box supported at the corners with metal reinforcers to take the strain of being hung on the wall, with 20cm (apparently approx 8" if I got my conversion right) of rockwool wrapped in black graden fabric to keep in the fibres with a hessian front cover to make it look a bit nicer. The windows themselves are plugged with a layer of plastic, a layer of quilted type material and then a slab of compressed chip board type stuff I had laying around screwed driectly to the window frame, then the frames hung over the top. They have nopticeably reduced outside noise, I used to hear birds etc outside in my recordings - now the extraneous noise from outside is restricted to the halfwit down the road trying to make 100km/h in the 100m's of road from my house to his and the occasional large truck working on the new appartments down the road. I think thius noise will be reduced even further once I have finished the last wall and done the roof according to Johns suggestion - well you can always hope anyway :lol:

Thanks again to everyone who's weighed in with advice on my build, as low tech and low end as it is :roll: Here are a few pics of the latest addition to the room, some over engineered window cover/plugs/ absorbers. They are made with a pine box supported at the corners with metal reinforcers to take the strain of being hung on the wall, with 20cm (apparently approx 8" if I got my conversion right) of rockwool wrapped in black graden fabric to keep in the fibres with a hessian front cover to make it look a bit nicer. The windows themselves are plugged with a layer of plastic sheet, a layer of quilted type material and then a slab of compressed chip board type stuff I had laying around screwed driectly to the window frame, then the frames hung over the top. They have noticeably reduced outside noise, I used to hear birds etc outside in my recordings - now the extraneous noise from outside is restricted to the halfwit down the road trying to make 100km/h in the 100m's of road from my house to his and the occasional large truck working on the new appartments down the road. I think this noise will be reduced even further once I have finished the last wall and done the roof according to Johns suggestion - well you can always hope anyway :lol: Nate