Actually ideally you need a 42" hood.

That's for a gas stove. Everything I read says that you don't need nearly the vent for induction as very little heat is created. So it's only for odors and not heat. Anyway I realized I can't go wider than 30" because of my windows, so it's going to have to be good enough. Fact is I have a downdraft vent now and I turn it on a couple times a year.

qofmiwok: What friedajune wrote above is essentially correct. For added background please review various hood threads published on this forum. Once you are up to speed we can provide refined advice for ensuring good performance.

kas

I am not participating in this thread anymore because the posters are stating their opinions as if they are fact. When this is the case you have no idea what to believe. So sadly, there is no value in participating.

It is stated "That is against every building Code there is." The truth is that the building code (at least as of now) specifically states that vents are not required for stoves. And according to other forums most cities don't require them either.

Which is not to say they are not a good idea. But people should not be scared into things with false information. I state this so people who come across this forum in the future don't assume the facts are correct.

Some other information was presented here which might be good information, but it is impossible to know. So I will stick to actual Houzz forums where many of the posters are Pros who identify themselves.

I am sorry you didn't like what I said.

Would you have preferred everyone tell you that a 30" hood over a 36" cooktop is good? Please do ask the "Houzz forums where many of the posters are Pros" about this plan. Here is the link to the Houzz Forum where HVAC pros hang out.

You didn't like what I said about a 30" hood over a 36" cooktop. What else didn't you like? Was it offensive that I advised you to check a hood's specs for its required duct size? Was it bad information that you should think about cfms in terms of the type of cooking you do? Or that a modern and minimalist hood will look cool, and that is fine, but a more effective hood has a canopy shape? Which of those was offensive? Which incorrect? Tell me so that I don't offend anyone in the same way the next time.

friedajune: Evidently we were insufficiently general to cover all possible bases, imagining that someone who asked about a hood wouldn't be interested in the legal possibility of no hood at all. Also, we neglected to note that in unincorporated areas, there may not be any code enforcement.

Usually, in the case of wall hoods, using a hood smaller than the width of the cooktop would entail having side cabinets intruding into the combustible prohibited space determined by the cooktop manufacturer. But then, that would only apply to wood and plastic cabinets and not metal cabinets without combustible contents, so shame on us.

There may be code restrictions related to cooking surfaces abutting windows, but I haven't looked them up. I imagine the grease patina will provide a unique view. Windows can be washed, of course, and ceilings can be repainted.

The International Mechanical Code seems to not require hoods for residences when the cooking appliances are used only for domestic cooking. (Ref. IMC par. 505.4; see also IRC section M1503.) Since code invention organizations continually expand their scope, we will just have to wait for that to change. Shame on us.

We can also admit that a 30-inch hood would be better (at least for the central burner or hob) than a down-draft vent. But then, to argue that assertion, I would have to write a lot of what I've already written here yet again. Shame on me for not doing so.

Nonetheless, the statement that qofmiwok made: "Everything I read says that you don't need nearly the vent for induction
as very little heat is created. So it's only for odors and not heat." may be true insofar as the limits of qofmiwok's reading, but technically is fundamentally wrong, assuming that by "vent" qofmiwok meant "ventilation flow rate." Maybe if she does enough research she will find out why, or at least what kitchen ventilation researchers who publish papers derive from their measurements.

As to avoiding future offense, friedajune, this will become progressively out of your control as the present generation of snowflakes drifting out of higher education establishments expand the scope of microagression to be all encompassing. So, feel free to be yourself.

kas

Since qofmiwok stated she wanted "Something modern and minimalist" maybe all she was interested in was looks anyway. So that being said - a 30" vent over a 36" cook top would look dumb (IMHO) from a design perspective. Hopefully her kitchen is her safe place.

Alright. Maybe one of the many similar glass canopy 36" wall mount hoods would work aesthetically in front of windows and meet everyone's minimal performance requirements. Google them or check AJMadison. 42" also available. This could look pretty good.

Perhaps qofmiwok saw the 30" - 36" HEIGHT above cooktop and transposed that to width; a few descriptions were slightly unclear in their meaning. However, even then, from what I've found (on HOUZZ) says wider than stove top is preferred as not all odors/grease etc go straight up but rather some to the sides and that narrower just won't do.