If it were my home, I would do as you're suggesting as far from
opposite the supply vent as you can get it. Don't cut studs, just
position the registers in between. For privacy, the louvers should
provide enough. If sound transmission is a concern, you might want to
vertically offset the vents on either side and use the wall cavity as a
short duct, lining the interior of the drywall (between your two cuts)
with a duct liner such as :
http://www.knaufinsulation.co.uk/out.../page_394.html to keep
the sound from bouncing between.

I don't think you have to create a frame inside your cut outs since
each stud cavity is likely sealed off. It certainly wouldn't hurt, but
is probably more work than is necessary.

I very much dislike doors that are undercut. For one thing, hot air
rises and an undercut door is sucking cool air out and leaving the hot
air in the room. Besides, it just looks bad.

"Vicki Szaszvari" wrote in message
...
wrote:

I live in S. Florida and want install transfer grills above the doors
of our bedrooms to increase the return air flow back to the main return
grill in the livingroom. Currently the doors are slightly cut on the
bottom but I don't believe it provides the proper amount of return air.

I would like to know how these are typically installed.
I will be cutting a how in the sheetrock on each side of the wall above
the door and will place about a 6"X12" grill on each side.

I need to know a few things:

If there is a stud which obstructs air flow; is it cut and braced
horizontally or just left in place and ignored.

To keep air from flowing from the insides of the wall, should I frame
it out with wood or just try to seal it off with pieces of duct board
and foil tape?

Will I need a baffle between the grills to reduce noise and retain
privacy between rooms? If so, can I buy these pre-made or is the an
easy way to make them myself.

I have not seen a home yet with a return duct system in South florida;
is this common practice?

Do you think adding the transfer grills is overkill and I should just
undercut the doors more? I hasd a quote from an AC Duct company and
they said that the new code requires these transfer grills.

Thanks for all opinions and advice,
Doug


Couldn't you use a transom?


Lets just cut to the chase scene then, and simply remove all of the
doors.....

--

SVL

Doug,

You are on the right track. You can't blow air into a coke bottle.

The return air duct your talking about doesn't have to be over the door. But
further away from the supply duct to the room is a good idea.

Commercial sites use 'cross-talk silencers' I think is the phrase. A duct that
goes up, over to the next room and then back down into the ceiling again. Any
decorative grill would work that allows the air to flow through freely. Remember
that a fan is pushing the air into the rooms and that same fan must suck it out.
So make it bigger than the supply duct. For sound isolation, the metal duct is
coated internally with this black fibreglass insulation. It keeps the sound down
a lot between the spaces.

You can make them up yourself or get a sheet metal shop to make them for you.
They do the insulation very neatly as well. Shape them to suit your construction
needs. As long as the over all shape is a big letter C, then it should work fine.

Dave


In article .com,
wrote:

I live in S. Florida and want install transfer grills above the doors
of our bedrooms to increase the return air flow back to the main return
grill in the livingroom. Currently the doors are slightly cut on the
bottom but I don't believe it provides the proper amount of return air.

Snip"