Is this a matching question? If I were using stainless steel appliances and hood, I would prefer a stainless steel wall covering over a galvanized wall covering. On the other hand, if spangles are your preference, then a galvanized surround would make sense. (I realize that galvanize can also be matte by spraying zinc dust onto the galvanized metal when it comes out of the liquid zinc hot-dip coating process.) Is this in a climate of scarce rain? Galvanize will eventually sacrifice itself to depletion and then rust will form.

Maybe the question was much different than my interpretation above. If the question is hood side overhang or hood front to back depth or hood flow rate then all of the relevant topics on this forum should be searched. Then adjustment made for expected effects of cross winds and whether capture in cross winds is a requirement.

kas

Matching is not that important. We're in S. Texas, not much rain. Architect picked the galvanized steel for the exterior for various reasons. Just trying to figure out what hood to get. Some have suggested vent-a-hood, but I have concerns about cleaning them. Have to measure again, but I think a 48" hood should be large enough to capture most effluent. I'm not concerned about total capture since this is outside, just don't want to get smoked out when the wind is pushing everything into that side of the structure. Contractor suggested we could go with an insert and use the same galvanized steel to keep everything coherent in look.