I assume you want it to vent out the ceiling instead of out the wall?

We are actually having it vent out the wall, but the chimney will go up to the ceiling.

Ours is “sunk” into the ceiling. It vents out through the roof.

The hood shroud gets installed into the cut drywall. Then any gaps are caulked. It’s seriously a 5 minute job if someone understands the problem and cuts the shroud correctly.

The ceiling is sloped and the installer cut it to the slope, but it isn't the cleanest cut.

If the cut is 'close', then caulk may be enough to conceal the boo-boo. It's not like it will be in your face way up there on the ceiling. Otherwise, ordering a new shroud and cutting it carefully will be the easiest way to fix it. (I would install the old one as a basis for a template to cut the new one. Glue some lightweight cardboard to the top of the old shroud butted up to the ceiling to mark the cut line on the new shroud.)

Thanks everyone! This guy doesn't seem to be great at making things look neat. Perhaps I'll do the caulking myself.

Cutting stainless steel neatly is difficult to do in the field. Cutting the sheetrock and recessing the steel into the rock is often cleaner. Or you could take it to a metal fabricator which can cut it properly

Ours isn’t caulked. The sheetrock was cut carefully (neatly). I don’t remember if it was taped and/or spackled around the edges. The stainless steel chimney passes though this opening (in the ceiling).

*We had to have the stainless steel cut with a laser I believe, in order to avoid “bluing” of the steel.

Water jets are another great way to cut metal cleanly and precisely. And it is very much something you cannot do on site

Did you end up getting it installed? We are getting ready to install our range hood on a sloped ceiling and I would like to purchase the crown molding but I’m worried it won’t fit properly.

i have the same problem. i have an ace up my sleeve my father in-law is a metal man. He will cut it with cut wheel. we put a straight edge attached it to the scrap end and cut along that straight line. then i used a finish wheel to smooth the edge. looks clean and correct. i used solid metal pipe in ceiling and connected to existing fresh air vents from bathrooms etc. kills me to see flex hoses laying in attic

kills me to see flex hoses laying in attic

Building code doesn't allow flexible ducting for vent hoods anyway. So, you did the right thing. Corrugated pipes are prone to collecting grease, and that poses a fire hazard.

For the same reason, you can't have any low points in your ducts. In fact, my local building inspector won't even allow you to have a duct that slopes down at any point. I didn't ask about level runs. But he was OK with our ducts that continuously slope up (or go vertical) from the hood to the exhaust on the roof.

Also, be sure that you use the correct vent cap and/or backdraft damper (if you have those). Equipment made for bathroom use will gunk up with grease and stop working.