I have the Bosch 500 series induction cooktop. I just measured the installed cooktop and we have 1-3/4" in front and 2" in back. I assume the specs you posted were for the cutout, not the installed cooktop. That said, I don't see how you could possibly have room for a downdraft in back of the installed top in a regular depth counter (I.e. 24")

All downdrafts require a minimum 27" deep cabinet rather than a 24", and even then, it's tight. They also don't provide very good ventilation. Overhead venting works much better as it works with the laws of physics instead of trying to work against them.

Using a deeper counter or pop-out cabinet also provides more countertop at the front and back of the cooktop. This can add useful strength if the countertop is stone. And the underneath front and back space allows more room for structural support across the 40-plus inches needed for the cooktop.

I concur with Hollysprings' view of down-draft quasi ventilation. If there is any practical way to avoid using a downdraft in a configuration, it should be adopted. If there isn't, then consideration of a different configuration is recommended, so long as ventilation of cooking odor and removal of greasy effluent before it condenses on the walls is actually desired.

kas

We have a Thermador induction cooktop and downdraft (Bosch twin, Bosch made) in our kitchen island.

Just now measured countertop and it is 33 1/8" deep, on a base cabinet that is 30 1/2" deep (this does not include doors, just the cabinet itself.) Island had to be that deep to handle specs of cooktop & downdraft.

I hope this helps.

If there is any way you can configure an overhead exhaust, do it. The downdraft unit is very inefficient (rather lame, really), but better than nothing. We had no other option.

Editing this post because it occurred to me that our actual cabinet/island depth might be deeper than necessary because we did a full kitchen remodel last year and we had the cabinets use the same footprint. So ... you probably do not need 30 1/2" depth. Just wanted to correct myself....

This post was edited by Cavimum on Mon, Jan 6, 14 at 18:02

One thing to watch out for when viewing pictures of kitchens that may not be real kitchens, whether poser kitchens in high-end homes for people who only have their food catered or demo kitchens in kitchen and cabinet designer offices photographed for advertising, many have inadequate or even missing ventilation. Most real kitchens such as reported in the Kitchen forum will have at least adequate ventilation. This can be achieved without going as far as the hood shown at the link below (not to mention its presumed make-up air system).

kas

Here is a link that might be useful: Handcrafted Metal Inc.

Hello Barbarav, I would appreciate if you could share what you ended up doing with an induction cooktop and the retractable downdraft exhaust? I have purchased those products (GE models) and am now trying to design a counter that will accommodate them. I thought I would put the cooktop in the island is the reason I purchased the downdraft exhaust, but now I re-designed the kitchen and put the cooktop on the outside wall. I would rather not have to eat the cost of the downdraft and purchase a different kind of exhaust. Also, I hope that the newer models are more efficient than when you first posted your question 9 years ago.

Thanks a lot! Martha