(4) CeilingBasic Idea
- putting on a ceiling that's not coupled to the joists, i.e. is not going to vibrate the joists. There are other methods, by adding new joists, the method I'm familiar with is screwing in special clips to a select few locations. And then attaching "hat channels" to these clips. These hat channels take the place of the joists in that you attach the ceiling to these hat channels. The idea being that the clips are designed to allow movement - and in so doing prevent it from vibrating the joists (thus keeping it from the rest of the house)How To
Step 0 -(BigMouthinDC edit - check every item in the ceiling that may be prone to rattling and secure. Wrap noisy pipes in an appropriate pipe wrap/insulation, insulate the ceiling with at fiberglass at least R19)
Step 1 - you're probably going to have to toe tap 2x4 (2x6?) between the joists at the end of the room. In this way you can attach the whisper clips close to the wall. (BigMouthinDC edit - If you have hardwood or tile floors above your theater space consider securing damped mass to the underside of the sub-floor, Two layers of 5/8 drywall with green glue will work start taming the problem. Cut the drywall in strips to fit.)
Step 2 - attach clips (diagram to follow as to what pattern to use - want to make each row about 2' from the neighboring (parallel) row, and within a row - spread out the clips - every 3rd joist (assuming 16" o.c.)- i.e. 1 every 4 feet. You'll have to double up closer to the walls, and want to alternate - so clips for one row are on a joist, that clips for the next row aren't on the same joist - to spread out the minimal coupling that there is.
Step 3 - attach hat channels. Probably will have to connect hat channels together to form longer lengths - use short self screw screws for this (make sure to mark where the hat channels are - so you can find them later). (BigMouthinDC edit - the clips are spread so that the weight is distributed between all the ceiling joists not just every 4th one,. Check with your clip vendor for additional clips to support structures you might add later like soffits.
Step 4 - attach drywall to hat channels as you normally would, and add GG, then another layer of DWtips: substitute a sheet of 5/8 OSB for the first layer of drywall in the projector location for mounting purposes. If you plan an elaborate ceiling structure you may want to substitute OSB for the entire first layer. First layer screw is 1 1/4 second layer is 2 inches long. Use screws intended for light gauge metal framing. Be sure to get 25 ga furring channel with hemmed edges. If the guy says he has 20 and it is stronger, don't be tempted. It is a bear to work with and will reduce the spring action of the assembly. (BigMouthinDC edit)MaterialsCosts
Pic of wood added between joists:
Pattern of Clips
View from below (i.e. laying on the floor - looking up at the ceiling) of rows of hat channels: With Drywall and GG and DW added- my apologies - in the pic the clips are not attached to the joists, or according to any pattern (still learning SketchUp :-) ) - also I didn't put the hat channel/clips on the wood added between the joists
Here's a pic of the drywall on the jack about to go up (jack very recommended (can rent at home depot) - unless working with a team)
gotta go to bed.. construction is tiring :-)