I'm not certain if this is in the PAC site or not, but I thought it was pretty nifty, to use a technical term. It is from this thread[url=http://www.avsforum.com/avs-vb/showthread.php?s=48505a795f5b53b1d7fec12af8e470c9&threadid=473081[/url]
The drawing was posted in BMP so I converted it to JPG, hence the posting of what is in the linked thread.
The idea could be applied to RC etc. also.
Discretely well hung;
Andre
Low celing RSICs
Originally posted at johnlsayers.com, topic 2709.
I've been planning to do the same sort of thing for a while.
In my case I'm thinking of using the Kinetics ICW springs, which require double perpendicular grid of hat channel. So the first layer of channel will be between the joists (1/4" below), and the second layer of channel will be lower than the joists.