CompleteNewb wrote:
....
...plan is to install a hood over the stove. The problem ...is that the
hood exhaust needs to stay straight ...no elbows.

...the stove is ...not against the wall ... outside ...

....
could elbow the exhaust as soon as it breaks into the ceiling of the
kitchen, go about 5' laterally (horizontally, along the ceiling, the width
of the kitchen), elbow again to go up, and come out through the roof on the
other side of the kitchen ...
...[ben] told ...kitchen hoods should NOT have ANY elbows,
should be a straight shot from stove up to outside. ...
... Will a hood not work well w/ 2 elbows in the exhaust?
If I used 2 elbows, would I need additional fans
at every elbow to help exhaust? Or would the fans not even help? OR, would
having the 2 additional fans be more complicated than just running straight
up through the ceiling/floor? Or am I thinking incorrectly that my plan
saves some work, and it would actually be EASIER to go through everything
going straight up?
.....

Straight shot desirable, not mandatory. The spec's for the exhaust fan
will prescribe the amount of outlet pipe length, etc., they can accommodate.

Not being able to see the actual building, which is actually "harder" is
impossible to determine and differing folks might have different
opinions on the degree of difficulty, anyway. I would say if you were
to chose the "jog" over that using two 45's to make the transition would
be much better than two 90s.

As for the roof exit, there are undoubtedly a multitude of roof
penetrations already, anyway. Properly done and flashed, they're not a
problem. One more won't make any difference although you might consider
where it is from an aesthetics viewpoint. That, in fact, might end up
being the deciding factor on which route to choose.

As for the function, if your cooking produces as much grease as you
imply, you probably want more than just a simple exhaust fan but
something more like a commercial exhaust that includes a grease trap.
Otherwise, the buildup problem could actually be a concern over time.

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