PVR wrote:
I am finishing my basement. One of the areas will be a family room.
There are 6 inch circular ducts running between some joists. I shall
install a drop ceiling using the Grid Max/Ceiling Max system. This
will give me a tiled ceiling about 2 inches below the joists. I shall
need heating /air conditioning in the family room.

Are there any registers available which I can attach to a circular
duct with a maximum protruding distance from the duct of 3 inches? I
have seen small circular registers which adjust by rotation of a
central knob but I don't know where. Can anyone help?

Peter.

If I am reading you correctly, you are planning to add additional
registers to ducts already there servicing other areas of your home.

Keep in mind that doing this is likely to mess up the air distribution
to the rest of your home and may well prove inadequate for your basement
room as well.

If you want this to work well, you need to have a professional do the
required measurements and calculations to assure that your present system
can handle the load and that your planed change to the distribution system
will work or if not suggest changes that will work. Otherwise you are just
trusting to luck.

Please ignore the above if those ducts are already feeding the basement
area you are remolding. You may find registers at your ceiling suppler or
you can find them at a real HVAC supply company.

--
Joseph Meehan

Dia duit