Update studio : new ceiling

Hi all, I am new here, but I find this place full of good pro advices. So here I come with my questions, but before, it is better I explain a bit the story of the stud I am from Switzerland and I bought a house three years ago and I did my stud in the double box garage below the house. I just a wall and a door to close the box. You can see the pictures of this work at www.pulseconcept.com studio section. The walls have been doubled with rockwool (80 mm) and plaster. The goal of this was to stopped the sound so that it goes no way outside ... The goal was reached ! My neighbour are happy and so I was. I say I was cause now I am not ;-) The thing that I totally forget was the ceiling. I was covered by sagex (polyethyrène) and I added one couch of decorative sagex ... Good looking but very poor soundproofing I play the guitar and sings and make music with electronic stuff (I told me no more bands). But I changed my mind, and the result is ... I play with a drummer and bassist now and the level we play is quite loud ... The walls are still ok, quite no sound outside the house (so no prob here) but for my wife it is a nightmare as the sound stays in the house ;-) So I am gonna update the studio by soundproofing the ceiling. Here is what is planned after having seen a lot of pro people. My ceiling is a "dalle à ourdis" meaning I have a lot of gaps in my ceiling. So I am filling theses %&/ gaps with acrylic mastic (hard and slow work ;-( Then (my command is already done) I will place the following stuff to the ceiling from top to bottom : - wood "squares" in order to do panelling ... I will glue felt on the top of the wood (the part that will be strecthed to the ceiling). The goal is to reduce vibrations (I dont have enough money to go into RC channeling). - between this wood pieces I will place isover R confort (www.isover.ch) it is glass wool but special for acoustic treatment. - then I will place idikell (it is an swiss produt like auralex sheetblok + but cheaper) on fermacell panels (18 mm thick). Fermacell is a very heavy and strong product (gypsum fibers) - these heavy panels (idikell + fermacell) will be fixed to the wood constructions (that will be screwed before to the ceiling) - then I will check the sound and see how much absorbing I need ... Question: The joint between the new ceiling and the existing plaster-rockwool walls will be made with silicone (I know I have to keep a 5mm gap between ceiling and wall) My problem is more about the walls. I explain the "I" are the walls and the "i" are the rockwoll-plaster walls). "S" is sagex (polyethirèen) The thing is about height of insulation before Old "dalle à ourdis" ceiling ISSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSs Ii Ii Ii Ii Ii Ii Ii floor Now it is like this "dalle à ourdis" Ceiling I <- that gap here should stayed empty ?(now I still have piece of old sagex cause to throw Ii all these unuseful material I cut it next to the Ii wall) Ii Ii Ii Ii floor What is the best solution ? a) or b) or c) ? solution a) "E" empty "w" new ceiling : glass wool and pieces of wood "p" : pannels of fermacell and idikell "dalle à ourdis" Ceiling IEwwwwwwwwwwwwwwwwww Iipppppppppppppppppp Ii Ii Ii Ii Ii floor solution b) "S" sagex ... lets keep it as it is now (after cuting the old material) "dalle à ourdis" Ceiling ISwwwwwwwwwwwwwwwwwww Iippppppppppppppppppp Ii Ii Ii Ii Ii floor solution c) "w" glass wool will filled the gap. With that case the ceiling insulation will touch the wall (not by solid way but by wool) old ceiling Iwwwwwwwwwwwwwwwwwwwwww Iippppppppppppppppppppp Ii Ii Ii Ii floor YOUR HELP IS WELCOME !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! thanks in advance bye PHil

nobody can help ? my schemas are not easy to understand ? thanks

for isolation you have to follow the Mass air Mass theme. I would concentrate my efforts to accomplish this to the best of your ability. There are many other factors that need to be addressed also, but that is the concept to design around. As you plan this members here will gladly help your design. Remember Mass air Mass is the best isolation.

THANKS so solution a) should work ... I ll see ! I know about that air mass thing ... that's why I put strong heavy things and then glass wool (light thing) ...

It would help a LOT if you can post an actual drawing of some sort - I've never been able to see anything from these ascii type "drawings", nor can I see what's "hidden" in those funny little "dot matrix" pix - Basically, though, Johnnygate's right about the mass-air-mass thing. What some people get confused over, though, is what is "mass" and what functions more as "air" - Basically, any material that you can NOT blow through is mass - even closed cell foam, which weighs nearly nothing, is technically "mass" and not "air" - A hollow concrete block wall is already a mass-air-mass system, because the air gaps in the blocks are just that - air. Any time you put a layer, no matter how thin, of open celled insulation (fiberglass, rockwool, mineral wool, slag wool, open-celled foam) you've just put in an "air" space - you only get ONE of these, then you're DONE - the mass on either side of that is then considered as two separate masses, with an air space between. I checked your website out and found no pix that would help explain your ceiling construction, but if you have smoothed out the wrinkles using some kind of patching plaster, then you need a wide, insulated, air gap and a second mass (this is assuming your construction ABOVE all this has no more "layers" to it. To help kill footfall noise from above, you may want to use resilient mounting for the inner leaf of mass - also, I'm not sure what is holding your ceiling up - before adding more weight, we need to clear this up as well... Steve

okay so I am gonna try to takes pictures of the ceiling and the we can go on with the talking ... true : I finished the first part of the studio with the mastic thing .. dont like that but i think it will help a lot for the db stop thing ... the mastic I use is a stop air thing so I dont thing a need to put a second one (it stays elastic even when it is dry) the dalle à ourdis is a system that mixed blocks and iron ways .. but I will post pictures ... (if I know how to do it in a post ...) like we say in french : "affaire à suivre" !!!

here are 3 images ... I ll try to put them in this post

the third one

the third has a problem to upload ...new try ok seems that the third is not able to be loaded but it is not a problem on the first one you can see what I call dall à ourdis with the old sagex .... on the second one you can see the wall that doesnt go to the ceiling (the blank) on the left a old piece of sagex and then it is empty ... so now you should better understand my ascii explanations ... thanks to respond bye

the round things on the ceiling are old pasting (for the sagex) ... no probs !

one more try .. I looked at the size of the files and that one was maybe a bit too big ... lets try

here you can see how I filled the gaps with the mastic ... on the picture with the wall (yellow) you can also see that ... the first picture is just the ceiling with no filling (yeah still lot of work to do) .... I ordered today : - 30 fermacell 1m x 1m50 x 18mm - 90 idikell 1m x 0,5m x 5mm (like auralex sheetblok +) - 22 pieces of wood of 5 meters - joint for fermacell I still have to order : - 5 piece of Isover (glass wool) of 15 meters each one - different things like screws and so on ... It is like I begin to see the mountain I will have to climb ;-) dont like that very much !!!!

bump !

Still trying to figure out how to answer your questions - Is this the product you call sagex? http://www.sagex.co.za/ IF so, it's light weight, not good for mass, and not an air space (EPS is closed-cell foam) Couldn't find much on "fermacell", other than it seems similar to gypsum wallboard. Mass loaded vinyl is normally more expensive for the same results as gypsum, and harder to seal/install/calculate - I tried earlier to explain the mass-air-mass principle, including what should be considered mass, etc - Now, I'm trying to figure out if you've already done some non-standard things and you want me to tell you they will work, or something else? Maybe you could re-state your questions now that we have a bit of background... Steve

okay so you are right about sagex, it is this "bad thing" ! ;-) the thing is my ceiling was totally covered with this sagex ... I removed it but not where i put "the new walls made of rockwool and plaster" .. you can see it on one picture the global question is : should I remove the rest of the sagex that stays between the new wall and the ceiling before putting the new ceiling ? If yes, should I leave this space empty or not ? If not with what should I fill this space ? Better this time ? thanks to answer all my posts !!! PS : I think I didnt thing I have beeing doing non standard things ... PS2 : you can find fermacell on www.fermacell.com. Yes it is like gypsum but stronger and heavier

the picture I talk about is : ceiling2.jpg .. you can see a piece of sagex on the left between wall and ceiling

bump :cry:

I’m thinking that about the only way you will be able to block the sound from your upstairs is to build an inner room - this would mean removing ALL the Sagex, and framing walls that are strong enough to support a new ceiling frame which would get filled with rockwool and 2 layers of gypsum under the frame - you need a true mass-air-mass envelope in order to stop the sound, and I’m not sure your concrete ceiling structure can support that. Plus, you’ve said you don’t want to use resilient hangers so you will need separate frames to isolate from the upstairs. Can you post the height of your studio so I can estimate whether there is enough room to do this? Thanks… Steve

Hi steve ! I have been working all the week-end since friday in order to : - finishing filling the gaps .. in total I used something like 70 "bootles" of mastic ... Endly I am finished with that - preparing the room for working ... meaning emptying and protecting the floor I begin the work tomorrow, so yes it is a bite late for advice from beginning ... As said I will fix the wood to the ceiling (with "feutre" in between) then between the wood structure I will place glasswool and then the idikell with the farmacell .. I will do the job with a professional so I hope he knows that my ceiling will support all the stuff ... I will be quite 30 kg per m2 ... Now it is too late to think about other solutions !!! the studio height is quite small as it was a double box from start ... it is like 2m 16cm ... so i cant bring too much space with this second ceiling ... something like 7cm in total ... I really trust idikell and fermacell properties to stop the sound and also the isover glasswool ... aargh tomorrow is the big first day ! cross the fingers for me bye

Hi there ! Happy new year 2005 ! I am finished with the new ceiling .. will be posting pictures very soon ... I am currently replacing all my gear inside the stud ... It has been a really hard and long work ... longer then I thought ... The main reason was that the man that should work with has broken his arm one day before the work as to begin ... bad luck I already did the very first tests with a boom boom radio and it seems that "noise" is approx. stopped by 50 % which is good for me cause the room is now empty and acts as a resonator ... So I really want to replace everything and do a real test ... The weaker point now is the door ... I think I will make a "sas" meaning a second door inside the stud ... but for the moment I just want to redo music again ... !!! bye

Yeah, the second door will probably do more for you than almost anything else at this point. Keep us informed on how it goes... Steve

yeah I think it too ! I think I wont do a second door but a big block on wheels that I can put in front of the door (in the outside of the stud) ... I have already design some primary plans ... I am happy with the new ceiling as more of 50 % of the sound is stopped and the sound inside the stud seems still good ! pictures will be posted here when I will have some time to do it ! bye

okay here are pictures !!! if I dont do it now I will never do ;-) first picture you can see the 1,2 tonnes of material laying on the floor and everything has to be fixed to the ceiling .. just one point : during the work I had to change the glas wool against rockwool cause the glass wool wasnt able to stay in place ... you can see one piece of idikell laying on the 30 pieces of Fermacell ... I use 3 idikell on one fermacell, so no need to cut ... one final piece was : one fermacell, three idikell and ... 50 kg ;-)

then you will see one during work with the yellow helpful machine to raise these heavy panels to the ceiling (fix them on piece of wood that were fixed just before to the ceiling)

and the last one to better understand the "system" I used ... more than 50 % of stopping sound with only 7cm loss of height on the studio .. thanks idikell and fermacell, the heaviest shit I know ;-)