Kitchen design question

[ChiTownZee]

If you have a 36 inch counter gas stove top do you have to have a 36 inch wide vent above? Does the vent requiremetns differ if it's gas or electric? I've always liked having the over the stove microwave with vent, but they don't make them that wide and I thought it would look stupid. Or I'd like a built in double oven with microwave, but they don't seem to make those, only double ovens, or single oven/microwave combos.

 

[greenhornet]

The last two places i lived in did not have a hood or vent and the house I'm trying to buy now does not have one ether. the house that Im buying also has pre fab metal cabnets from the 40 or 50.
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