to trixieinthegarden - if I use an undercounter hood, don't I have to revent the whole thing? Or do all the under mounted models use recirculating vents? Right now, I have a nice arrangement that vents to the outside (I'm in a freestanding house, not an apartment) and I was hoping to keep this configuration (trying to save what remains of my budget!) Most are configured to vent through the top or through the back, sometimes offering both options. If you use a top-vented one you should be able to re-use your existing venting, depending on your vent size. Most take a 6 or 8 inch duct. The only thing that would be an issue for you is that undercabinet vent hoods usually have keyhole hangers for the back wall, so you would have to mount a strip just under your soffit at the back to mount the screws for the keyholes to hang. The vents are also attached through the bottom of the cabinet above so that takes much of the hanging weight.

As far as I know, no, there are not separate downdrafts that work with anything but a cook top. Are you having cabinets above on that wall? You could use a completely integrated hood and run the duct through the top of the cabinets. It takes a lot more work than building a box but it would look better. You could then run it through the pantry. Look at Broan and Faber Here is a link that might be useful: Broan Power Pack

We used a Tornado II by Zephyr. It's an insert that we built a hood around to fit my situation. I saved quite a bit of money by buying my insert directly from an ebay dealer that I bought almost all of my appliances from. (saving-u-money) is his eBay handle. I can provide more info if you want to compare prices. Here's a photo of my hood. Though not completed, you can see how a liner works. You can also download a PDF info from Zephyr that will give you a drawing, schematic, and other info that will show you exactly what you will need to do this. I love my hood. The photo online shows that they've redesigned it a bit. Mine actually looks like the Tornado III, but I know it was a II with 1,000 CFM. FWIW, I love my hood. It's a powerhouse and doesn't blow you out of the water. It's a solid whooshing sound, not whiney and tinney. My brother lives next door about 300' away. (We both have 1.5 acres.) He has called me before to ask, "When's dinner?" because he can smell what I'm cooking. My kitchen vent is away from his house, too. When I've told him that I'm not grilling and I'm cooking inside and not outside, he can't believe it. It has to be this powerful hood. Here is a link that might be useful: Tornado II

building2017 wrote: ... - What are the silencers I have read about and how do they work/would they work here? These are like giant truck mufflers, except designed for various diameter ducts. They have low pressure loss (forget the value but it is a lot less than baffles). Fantech is the source. - Any benefit re:sound to using two smaller liners instead of one big one and only using one at a time when using only one side of stove? Or is this magnifying the cost for no good reason other than sound? (Because I'm assuming I'd then have two runs up and out and two things on the roof because they wouldn't combine to avoid a turn and to ensure proper function? If only one side were run at a time, then MUA costs could be lower, but where code requires MUA, I am willing to bet a donut that the AHJ will demand an MUA system that can handle both at once. In theory, the sound reduction will be only 3 dB less. Also, when using the central burners, you will still need both systems for capture and containment. Well, I guess three things on the roof then with the MUA. While commercial systems mostly use roof MUA entry, and I use roof MUA entry, the options for residences are wide open and may include side of house entry, or entry into a basement that has an air path access to the kitchen.