As noted above, maybe a liner (hood without a fancy exterior) would be best for wood integration. I have a Wolf Pro Island hood, and it fits my desired hood height under an 8-foot ceiling by using a 1-foot extension. A seven-foot ceiling would seem to match the hood (or its equivalent liner) without an extension. In any case, island hoods are intended to duct upward, so you either have to put a bend in where the beams are, or continue through the ceiling. It is too bad that the main beam passes close to the chimney that you want to center the hood on. A large, quasi-commercial style hood at the ceiling could provide a large enough capture zone while being perhaps less obtrusive. Besides the question on the chimney sectional area, there is a possible issue with grease transport through a normal chimney, not that it hasn't been done for centuries, but then the heat source was a hot wood fire. The cooler internal tiles or whatever are being used to line the chimney will tend to collect grease more easily than thin sheet metal ducting that will tend to warm quickly. So the same issues as with wood creosote build-up may be in play. Also, using the chimney forces you to use an internal blower at the hood, rather than an external blower on the roof or exterior wall. An internal blower will be noisier for a given blower design and flow rate. What is above the ceiling by the chimney? kas

I'm actually wondering the same thing. I currently have a very old Jenn Air downdraft cooktop on an interior wall, so the ductwork is already in place. For budget reasons, we don't want to change the layout of our kitchen too drastically (relocating plumbing, etc.). I thought I was ok with a OTR microwave with a recirculating hood, but now I'm wondering if I should reconsider a downdraft setup. Does anyone have a new Jenn Air downdraft range? Does the venting take up space behind the range, or could it stand on its own? I'm considering a gas slide-in model, but I can't figure out where the space for the venting needs to be. Also, are Jenn Air ranges any good, or are they just overpriced niche proucts? I'm also considering a telescoping vent by Dacor, but I can't figure out if it can be installed behind a slide-in range or if it can only be installed behind a cooktop. Basically, I want to preserve the storage space under the cooktop, and I'm wondering if that's possible.

marthavila: sounds like a good decision based on good advice. All the cfm junkies on GW are nodding their heads. Both changes will reduce noise: the duct upsizing reduces the airflow turbulence, and as you note, the larger blower may run at a lower speed with same cfm output as a smaller unit running harder. The latter is particularly true if you do have a continuously variable fan speed control so you can "fine tune" the blower to what you're cooking. I have a somewhat different take than trailrunner however, on the issue of airflow speed and grease handling. In general, the concept of a well-designed hood is to trap the grease before it enters the ductwork. Once it's in the ductwork, all is pretty well lost, especially if the duct run is at all long. Much of the grease will end up on the duct walls, never to be removed again. As a result, different hoods use different systems to trap grease. There is the Ventahood "squirrel cage" system, which uses a centrifugal fan that theoretically flings the grease particles into the fan housing, where it is trapped, while the air continues up into the ductwork. There is the mesh filter system, which is similar to what is used in most (barely useful) recirculating hoods and UC MW/hood units. The air flows through a metal mesh that is supposed to trap the grease particles. Then there are the baffle systems. These use a system of alternating U-shaped baffles that force the air to make two abrupt 180 degree turns before heading out the duct. At each turn, the grease particles that fail to negotiate the tight turn are trapped by the baffles (and shameless bias--the polished stainless steel baffles on our new MA hood are gorgeous! Almost too pretty to hide under a hood). High airflow speeds likely do not increase grease trapping efficiency: I could imagine that overly high airflow might even facilitate more grease making it past whatever filter system is being used. The reason that high cfm are desirable is not so much to whisk grease out the ductwork, which is unlikely, but to exhaust as much of the fumes/smoke/odor/grease from the temporary confinement in the body of the hood before it can spill back out of the hood into the kitchen. The combination of large capture area, a deep hood, and a high cfm blower should give maximum f/s/o/g evacuation. But totally concur with trailrunner's advice about starting the hood early and letting it run afterwards. Definitely will help.

Wow, I'm very grateful to all of you who took the time to reply! Great to see your pictures, too. Some responses (if you're interested), now that I've finally been able to go through: Sammy and The Kitchen Place are correct that we could put it in the upper above the dishwasher — that's the only upper that is the right size that wouldn't block other cabinets. (Thanks for the pictures, The Kitchen Place!) I was intrigued by nidnay's idea of bumping into the bedroom closet, but that closet is filled with custom cabinetry so it would be a huge project to put the microwave there.If Icould put a Miele microwave (/speed oven) in an upper cabinet, I'd try for that, but of course our uppers are only 13" deep and the Miele opens down, so not workable. My better half is against mounting a "normal" microwave in an upper cabinet (he thinks in that case we might as well go OTR, and that it will pull away from the pretty stove/hood that's the whole reason for this conundrum). (ci_lantro questions the whole premise of opening the kitchen. Others in our building have done it and it makes a significant difference in the feeling of the whole unit—we're confident it's the right move, long term.) Helen, HU-41121833, Buehl, Interior Concept, RTHawk and others: Thanks for saying good things about the Sharp microwave drawer. nidnay, thanks for your criticisms of it, too! The slimline microwaves are attractive too! Unfortunately induction sounds great, but not in the cards for us. I do believe everybody who says we need something more powerful than a microwave fan — the Vent-A-Hood system does look quite good. kaseki, thanks for your hood comments. pittsburrito, I hear what you're saying about external ventilation. There is a small vent in the kitchen and windows in the living room, so we try to be careful. Thank you all! Still not sure what we'll do, but I'm grateful for all the advice on the Houzz forums.