In article ,
"David F. Eisan" wrote:

All the electrical from the interior walls has been moved or removed. The
HVAC ducts have been rerouted to the outside walls and tucked into a soffit
that runs around the main open room.

So you are stuck with the soffit, since it's full of ducts and what-not.
I'll offer a few variations other than what I've seen mentioned so far -
some may not make sense depending on ceiling and soffit bottom height.

Personally, I hate the texture, and associate it with cheap apartments
trying to disguise the crappy drywall job on the ceiling. Do a good job
and use a flat white so that you don't need to do a "perfect" job, as
gloss will shine up even tiny defects.

Coolest, but work - Cove it. Drop a nice convex curve from ceiling to
wall that allows space for the ductwork, make frames to hold the curve,
and either wet and bend drywall or use plaster and do it right, make
nice mitered corners, stunning effect. Tall furniture and short walls
could be a problem.

Craftsman-style ceiling - park a molding/picture-rail/crown on the wall
- everything above is "ceiling", everything below is "wall" - more
commonly seen dropping a 10 foot ceiling to a 7-8 foot "human scale"
visually.

For crown molding with the rectangular soffit, you can double your
pleasure by doing from the wall to the soffit, and from the soffit to
the ceiling - probably better with two different moldings.

You can get a nice effect by painting the soffit a color different from
the walls and ceiling (it's there, make it a feature since you can't
"hide" it.) Say you have blue walls and a white ceiling - paint the
underside of the soffit a lighter blue, and the vertical side a darker
blue - either darker than the underside but still lighter than the
walls, or boldly going darker than the walls. The vertical is a good
surface to stencil, if you're into that sort of detail.

You could also do some serious woodworking - raised panels set into
stiles and rails along that vertical surface (atoning somewhat for all
the 1970's soffits paneled with that lovely fake-wood panelling nailed
up). You could also take that look down around the bottom, if you wanted
to.
Then again, you could go for a slatted look - nail on battens, paint the
undersurface and battens black (or perhaps some other color - black is
typical for trying to make the support "disappear") then put natural
boards over the battens spaced 1/2-3/4" apart.

--
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