First, a warning -- I have never lived in a house that needed make-up air. Not even close. Double-pane glass makes little sense for us since all the heat goes around the sashes in our Victorian. My experience with MUA is related to commercial systems. What follows is an opinion about the kinds of things that would make me consider MUA. Unless you have a Code requirement for make-up air, you have a fireplace you use when cooking (I seem to remember that you are South Bay?), have a "naturally" vented gas appliance in "connected space" (no always-closed doors between the hood and the appliance), or have a "tight" house (recent, energy-efficient construction, most likely), I would skip MUA. Even if you do need MUA, the difference in the maximum hood flow probably wouldn't significantly influence the the cost of the MUA system, which I would think was primarily labor driven. If not significantly more expensive, and you can run at least an 8" duct (preferably a 10"), I'd go with 900 CFM for two reasons: * You have it when you need it -- guests over, and the kitchen fills with smoke... * A 900 CFM blower at 600 CFM may be noticeably quieter than a 600 CFM blower at 600 CFM The 24" will serve you well. Enjoy your new range!

I encourage you to review the many hood threads on this forum. At the moment I cannot write another tract on this topic; maybe more is possible in a few days. The short answer is that as the hood height above the cooktop increases, the hood entrance aperture area has to increase to capture the rising and expanding cooking plumes' effluent. (And this may have to increase further due to cross drafts, where present.) Hence, the required hood aperture change increases as the square of the height change. Containment requires a sufficient air velocity at the aperture, so the blower flow rate has to increase proportionately to the hood aperture. The make-up air system has to similarly grow. These factors mitigate against very high hoods for residential settings unless commercial solutions are acceptable. Effective ceiling vent systems do exist, mainly in commercial settings. Standard height above the floor for the base of many common commercial hoods is around seven feet. A Wolf Pro Island hood will work well over an island or peninsula if it is long enough to overlap the effluent cones at the hood height selected. I wouldn't go above 36 inches above countertop height, however, unless some missed effluent is acceptable. A suitable roof blower and in-line silencer will keep the noise down for normal conversation. Here is a Wolf hood covering a 36-inch induction cooktop plus a nearby induction wok. You should be OK with a 42-inch wide or longer hood if you don't go too high. See the Wolf Design Guide (.pdf) available for download at Wolf/SZ's web site. kas

Does anyone have the Wolfe 36" contemporary gas cooktop. If so what material did you put behind the knobs and are you happy with the cooktop. I plan to purchase in a few months.

Julie , I don't think that is necessary or in the manual guide for install to do that. My builders had input from where we bought appliances and cabinet makers and thoroughly reviewed Wolf instructions. It is just the gas coming out is louder then the other two. The technician said it is completely normal ! But the way its built the gas makes a bit more sound when coming out of those tow burners. I understand I loved having help, and getting opinions. It really is a sleek unit I don't think there is anything else out there with that " look". plus it is bigger then most drop in units.