I have attached the plan here.

It is the nature of hot, greasy, moist cooking plumes to rise. Searing and stir frying plumes can reach velocities up to 1.2 m/s. Diverting plume momentum to the side or downward is possible with an enclosed fume hood, but not with the devices attempting side-draft and down-draft functionality for residential kitchens. They work for low velocity steam emitted close to them, as well as similarly low velocity plumes from simmering.

I recommend leaving the cooktop at the wall and revising the window plan. Put a prep sink on the island and a real sink next to the dishwasher, wherever it is.

Or anticipate having a "chimney" duct from the island through the ceiling to the roof with a proper island hood above the cooktop.

Do not design a kitchen with serious cooking equipment requiring an appropriate CFM hood system without designing in parallel the make-up air system.

AB Normal - I don't think we're trying to install too many items, and I'm willing to forget the magnets - not as important as proper ventilation.

Kaseki- Thank you for an informed opinion about the air flows. I am sure the engineer will agree with your assessment - I'l just make the process a bit more straight-forward and ditch the downdraft idea!

Hi! Can you share how your experience has been with the Gaggenau downdraft? I am considering one for my own kitchen remodel

Gabrielle -

The project isn't done yet, but after I received a quote for the downdraft units, it was a no-brainer to go with the range hood. The cost increases because multiple units are involved. If I'm not mistaken, the cooktops and downdraft setup were going to run around $30,000. The hood and blower were more like $7500. I'd had concerns about the downdraft and wasn't going to pay a huge premium only to find out it wasn't very effective. I hope that helps you with your decision.

Gabrielle, I am so thankful to read your post. I am starting a remodel and have to do a cooktop in the island. Like you, I love the look of the Gaggenau modules induction/gas with downdraft. I had no idea the cost was so much more. I will have to re evaluate now. My other option was a traditional Wolf gas cooktop and down draft. What did appliance brands did you choose?

Hi Kel,

We're still early into our kitchen remodel. But I still have my appliances set on Gaggenau. Thankfully, there is
a Gaggenau showroom nearby to us and we will be going to view and see it all in action.

Unless we see that the downdraft is completely ineffective, we will be getting the vario cooktop.

Gabrielle - This was the layout they priced for me...1 induction, 2 separate gas modules, and 1 wok module. In this configuration, there are three separate downdraft modules, which is why it was so expensive. If you go with just one 36" gas or induction cooktop, you only need one down draft unit, so that would be a sizable savings compared to this layout - similar to what they show on their website.

Good luck!

The other thing you need to discuss with your HVAC contractor or engineer is make-up air. The Gaggenau hood is rated 620 CFM.

Depending on where you live, the building department may also require you to replace the air removed by the hood (make-up air) if the hood exceeds 400 CFM or 600 CFM, depending on the locale.

So no matter where you live, don't forget to address this early on in your appliance budget. I was advised that a hood drawing less than 500 CFM is almost useless, so that might be a factor with downdrafts, but it's worth paying attention to the blowers' specs when deciding and asking your local HVAC contractor what they suggest.

Laura!

Thank you so much for providing more details.

We haven't been priced out yet but are considering the 15in induction, 15 grill and 15 teppanyaki. With 2 downdrafts in between. When emailing with the Gaggenau showroom, I mentioned I was concerned about the effectiveness of the downdraft. They shared they have a new blower but I'm not sure about the CFM.

For our home, we have vaulted ceiling in the kitchen and also have a kitchen window nearby. Not sure what the HVAC contractor will have to say about it yet though.

I certainly appreciate the appeal of your configuration. I ended up with the 15" induction and bought a teppanyaki pan to use with it, and then the 36" cooktop with the wok and 4 burners. I considered a grill, but our architect advised against it - said it was a mess to use and to clean, and that most people end up not using it. Your needs may be different than mine, of course, but I prefer a charcoal grill. If you really want a sear, a salamander, as used in commercial kitchens, would do the job, but it's unsightly. I looked into an outdoor salamander, but ultimately don't think I'd use it much, so I just punted on that. My kitchen is supposed to be done by April 15th. I post the installation. Fingers crossed.

Laura, How exciting you are almost done with your kitchen! I'm considering the 15" induction with the cooktop on my island. (not possible to relocate). Can you just use the retractable downdraft with this configuration vs. having the downdrafts in between or do you need both if no overhead hood? I really love the flixibility of options along with the design of the Gaggenau but I'm worried about lack of service people in my area. I may just go with Wolf and skip the induction but would still like to research it. Thank you for your feedback.

I dont know about that so you will have to ask Gaggenau they sell those pop ups that might work with both modules one thing that caused me to skip Wolf is that the gas unit and induction unit had different trim. when installed side by side they won’t match! that’s s design crime given the wolf level price i wasnt going to pay that kind of money and have the cooking area look like a hodgepodge. they may have changed that detail this year but make sure you check it out at a showroom. sorry about no caps or punctuation there is sime kind of glitch

The laws of physics has not changed. Downdrafts of any brand are still virtually useless. The correctly positioned capture area of a traditional overhead hood is the key to keeping your home and your lungs clean of nasty greasy cooking byproducts.

https://med.stanford.edu/news/insights/2018/03/use-your-range-hood-for-a-healthier-home-advises-indoor-air-quality-researcher.html

HJ- I agree.