Basement ceiling already drywalled, best course of action?

Hi everyone,,,,first post. John...greetings! I'm starting a basement studio and the ceiling alraedy has drywall on it. I've considered adding resilient channel and another layer of 5/8 drywall. Will this do any good? Would a tear off and start-over be worth it? I'm trying to keep expenses down, so items like Aurelex sheelblock would not be the first option. PS, we'll discuss walls later.

Greetings and welcome to the site. If you would, please update your profile to include what part of the world you're in. If you haven't done so yet, read through some of the posts here: http://johnlsayers.com/phpBB2/viewtopic.php?t=2125 Lots of good info.

I'm starting a basement studio and the ceiling alraedy has drywall on it. I've considered adding resilient channel and another layer of 5/8 drywall. Will this do any good?

If you already have drywall and are thinking of adding RC and another layer of drywall, you're getting into a 3 leaf system. (the link above will give additional links and describe this in more detail).

PS, we'll discuss walls later.

Keep in mind, the entire construction works together as a whole to achieve the best TL and isolation. :D

I'm wondering which of the following options would be best (from top to bottom): existing 5/8" hardwood floor existing 5/8" plywood existing 2X8 joists 16" O.C. existing 1/2" drywall with "popcorn" Add 1 layer of 5/8" drywall screwed to joists Concerns: airspace between joists is inaccesible, no insulation or caulk and 2 untreated 6" ducts run to registers in the floor. existing 5/8" hardwood floor existing 5/8" plywood existing 2X8 joists 16" O.C. existing 1/2" drywall with "popcorn" Add RC-2 resilient channel Add 1 layer of 5/8" drywall Cocerns: Would this suffer from the "3 leaf" syndrone, and again, untreated airspace/ducts. Tear out existing drywall, treat airspace and ducts with insulation and caulk and add RC-2 and 2 layers of 5/8"sheetrock Concerns: Lots of work, trash and time...I'm already crippled from moving 4X12X5/8 sheetrock. Would this be worth it to protect my family from hearing the same song 300 times? PS: I am considering wall design to work in harmony with the ceiling.

The best isolation will be the last option. If you currently have no insulation, etc in those joists, I would suggest removing the old drywall and insulate the ducts and joists. RC2? If I remember is two legged.? I used RC1. RC was originally designed for ceilings to help level them. The RC1 only attaches on one side and when the weight of the drywall is attached, it helps to pull it away from the joists and decrease vibrations into the structure. :D

I'd be more concerned with why you're playing the same song 300 times! Kidding. Takes me that long to get a decent guitar solo... Couldnt you blow in some insulation, scrape the ceiling of the acoustic and add another sheetrock layer?

He could, but that would still leave the ceiling UN-isolated from structure; for this type construction, NOT using resilient mounts or separate ceiling frames is usually NOT an option, unless your family happens to think your 300-play song doesn't get heard nearly enough... :? Steve

To avoid the controversy I tore down the drywall ceiling today. Now the plan is to use RC-1 channel with a layer of 1/2" drywall and a layer of 5/8" drywall. A couple things still aren't clear: There are two round ducts between the joists that run all the way across the room and feed registers on the floor above. How does one treat these ducts to prevent sound from travelling out the registers? There is currently standard ~4" thick fiberglass insulation between the joists. I'm getting 2" thick rigid fiberglass board from a friend to place in the ceiling. Would it be best to place the board in contact with the plywood of the floor above or place it in contact with the ceiling drywall. I would use the standard fiberglass to fill the remaining void. (is the point of the rigid board to fill the area between the joists or to contact either floor or ceiling surface for damping/absorption?) Once again, thanks all.....

There are two round ducts between the joists that run all the way across the room and feed registers on the floor above. How does one treat these ducts to prevent sound from travelling out the registers? If these are metal ducts, you need to either insulate them with rigid fiberglass pipe insulation (comes in two halves, you duct tape them together around the pipe) or, especially if these will feed the studio, remove the metal ducts and replace them with flex duct, being NOT careful to run it in straigh lines but more like a drunk snake track - These ducts will be in between the two masses of your mass-air-mass sound barrier, so will get some sound leakage; if there is room vertically, you'd be better off boxing them in with cleats and wallboard (2 layers) and filling in everywhere possible with insulation. There is currently standard ~4" thick fiberglass insulation between the joists. I'm getting 2" thick rigid fiberglass board from a friend to place in the ceiling. Would it be best to place the board in contact with the plywood of the floor above or place it in contact with the ceiling drywall. I would use the standard fiberglass to fill the remaining void. (is the point of the rigid board to fill the area between the joists or to contact either floor or ceiling surface for damping/absorption?) The point is both; if you have insulation contacting both inside surfaces of the barrier with light to medium pressure, it will damp both membranes and improve isolation a few dB - putting the heavier insulation on top will require a way to keep it there, or it will sag; this crushes the other insulation, allowing the rigid stuff to fall away from the upper floor and reduce whatever damping you might have had. By putting the heavier stuff on the bottom, it will contact the lower ceiling panels by gravity; this will also leave the lighter stuff LESS compressed so it should remain in contact with the upper floor sheath... Steve