Hi Dan, Apparently the most important sound proofing is to eliminate air spaces. Sound travels through even small penetrations. Oddly then, dust proofing is already an important sound proofing function.
There are special glass fiber and other insulations which improve on the more general heat insulation characteristics of the usual pink insulation. You would need studs at 8 inch centers if you offset them, you could probably get away with drywall on 24 inch centers I suppose but it would be inconvenient if ever you want to hang anything on them. You might like to hang 3/4ths plywood then thin sheet rock over that on the shop side at least where you can then mount anything anywhere by running screws through the thin drywall veneer and into the plywood. The extra density would also help to kill noise. Now I would consider some sort of strip rubber or even a rubber like membrane across the studs before applying the wall sheeting. This would isolate the panels from the timber except for the attaching screws. You save two inches and you build in the sound damping. If you form it around the back of electrical boxes you will also stop up any holes for sound to penetrate through. Failing a membrane and I don't know where you would get something suitable, you can get rolls of that poly foam. You would usually use it on the underside of the 2 by 4 you lay on the floor and along the one at the wall to form a good seal, you might like to double it and get it wide enough to run up the edges of those boards. The edge of each stud would be covered. I would also consider stretching a layer of that 6 mil poly vapour barrier. Though a little more expensive, in this case I would consider the heavier stuff which is also UV rated for exterior use, it is a lot easier to handle. Staple this to the stud wall, bring it up over the ceiling, then fold up the poly foam over the vapour barrier and add strips to the studs then apply the plywood and the drywall if drywall is what you want. A thin layer of drywall does provide a good surface for paint and is easily repaired when necessary. Treat the ceiling as you like but again, if foam isolates the ceiling material from the strapping holding it up you shouldn't get a lot of sound transmission and if air isolated there isn't a passage for sound to leak. The electrical box in the ceiling and switch boxes and plug boxes should be air tight too, there are now those plastic ones which are essentially sealed. You could use something like faucet washers between the ceiling strapping and the under side of the floor joists as well to further isolate them. For rigidity and to make erection easier you should run a cross member between the floor joists to fix the top of the wall. Now apparently the correct way to do this is to construct the wall a little short of the fixing struts, drill holes up through the top plate of the wall then spike or bolt up through the hole, across the space and into the support struts so that there is a bit of room for vertical movement. Apparently in some situations movement of the building up and down can cause problems when the building settles down on a wall which does not compress. I should say here that I have never actually seen it done this way personally but that is how it is recommended. In your case this would provide you a rigid wall and a pretty decent measure of sound isolation at the same time Now as I remember you have a steeply sloped floor and sometimes some water issues. You might consider fixing the bottom plate through enough thickness of something like extruded Styrofoam which could more easily be shaped to the contours of the floor with a good rasp or even a belt sander. Though a little compressible, with the weight spread out like that it would be relatively easy to turn an uneven floor into a nice flat surface. Your door should be a good fitting one and consider weather stripping it against noise. After all that you may wish to introduce some deliberate ventilation. The room will be quiet though. Hope this gives you a few new ideas. Dale leavens. ----- Original Message ----- From: Dan Rossi To: [email protected] Sent: Saturday, January 03, 2009 1:34 PM Subject: [BlindHandyMan] Noise reduction. So, in the fantasy world in which I live, one of my projects is to wall off one end of my basement to make a shop where I can go and make dust and noise without getting dust and noise all over the rest of the basement and house. I realize I won't make a sound proof room, but I would like to take some steps to reduce the amount of noise that will bleed out of the shop area. Here are some of my thoughts, any corrections, additions, or ridicules will be accepted. The wall will have a footer and header that are 2X6 instead of 2X4. Then there will be studs staggard two one edge or the other. Thus, there will be no stud that reaches from edge to edge, so no bridging. The cavity will be filled with fiberglass insulation. The dry wall on the shop side will be mounted to Z bars instead of directly to the studs. Lots of fiberglass will be stuffed up into the joist bays overhead and then acoustic tile as a ceiling. One major question I have is dot dot dot. The wall runs parallel to the joists, so should I run the top of the wall up between two joists, but not fix it to joists or floor and then stuff lots of fiber glass around the top edge, or do I absolutely have to fix the top of the wall to something. Obviously, there is a rigidity issue if I don't. The ends of the wall can be fixed to the cement walls of the basement, if that is enough of a substitute. Most of the sound will be high frequency sounds so doesn't fiber glass batting and sealing up cracks take care of most of that sound? Without trying to make a sound proof room, are there any other things I could do to reduce the sound bleed? -- Blue skies. Dan Rossi Carnegie Mellon University. E-Mail: [email protected] Tel: (412) 268-9081 [Non-text portions of this message have been removed]
