who is "many people" ? and why didn't they tell you about the 27"?

This is not a standard depth for hoods. If you were to mount one at "normal" heights most people would constantly bang their noggin into into it when using the cooktop.

If you really want one and are mounting it such as not to hit your head AND still be effective - then you are looking at a custom design and fabrication, which is beyond the scope of this forum.

Modern-Aire makes 27" deep hoods as a "standard option" in their hoods.

A 27" hood will come roughly to the front of the handle on a pro-style range, potentially a walk-by head-banger if mounted in the 5' to 6' off the floor height (above eye level, but not enough to clear your head). If you're in the 27" deep hood market, you are hopefully considering enough CFM to handle a 6' high mounting.

24" is the de facto standard depth for better-quality hoods, possibly as it sits back from the countertop edge by about an inch. In my opinion, Modern-Aire, Prestige, and Independent are makes in this price range worth looking at.

Mainstream hoods are typically 22" or less in depth, often with a capture depth much less than that (wide edges for controls and/or lights, or limited baffle/mesh area and a shallow "face" underneath).

Although 24" is a standard depth for pro hoods, many of the pro hoods come in 27" depth. In fact, 27" is recommended for ranges or rangetops with grills and griddles. Both Viking and Wolf make 27" deep pro vent hoods. I know that having the largerst possible capture area is key. But I'd love to hear from anyone with a 27" deep range who thinks it is overkill or who wouldn't get one that deep to do it over again. From the point of view of aesthetics, I'd love to go only 22" deep. But I'm shopping for a 24" deep for function.

We have 27" and would do it again. 27" is a common depth for hoods, and with some it's the only size you can can get warming lights. I'm 5'10", hood is 30" above range with no head bumping, but range and hood are on the inside of a "U" so there's not much side to side movement around the range. Our locality has rigorous building codes, and there were code issues about the hood extending to the edge of the range given it has a grill.

teach -

if your countertops are at the customary 36" ht. and your hood is 30" above that - how can you not bump your head if it's 27" deep? That puts the lower edge of the hood at 5' 6" above the floor?

I have to disagree with you on the commonality of 27" hoods. They are available, but far from common. Most manufacturers don't even make them that deep.

Vent-A-Hood offers many hoods in 27" depth. They are not, however, under-cabinet hoods. You need to go with an 18" tall model get a 27" in depth. See the link below. Most of the pictured models are available in both 24" and 27" depths.

Here is a link that might be useful: Vent-A-Hood wall-mount range hoods

I guess if you exclude VH, Wolf, Independence, Viking, Thermador and some other hood suppliers, you're right, there's not much out there that's 27" . . . All the brands we looked at had 27" models.

As for bumping head, think about it for a moment. You can't stand directly under it because the range is sort of in the way . . . This causes one to lean forward when cooking which reduces your height. We were a little concerned about this and had the construction crew hold the hood in place at different heights and at 30" we were clear. 5 years later still no need for helmets.

This is how a 27" deep hood looks in profile above a pro-style range. The hood sticks out less than the oven door handle, and is about even with the front edge of the cooktop.

It's hung at 6 feet.
Casey

Casey great pic !! I just love your kitchen. This would explain the need for 27"...I was scratching my head wondering how I would reach my cook top LOL. Ranges are WAY deeper than cook tops. c

Casey--this is pretty the same setup I have--could you fill us in on the ceiling fan, or perhaps better put, the fan hanging from the ceiling? Most intriguing . . .

Remember one simple solution is to use a 24'' hood and bump it out a couple inches, using a filler strip between the back of the hood and the wall. This works well especially if you are using a hood surround and liner, an undercabinet hood, or a hood flanked on both sides by cabinets, so that the filler is invisible.

That gives you the flexibility to move the front edge of the hood out exactly as far as you want. The dead space at the back of the hood should not significantly affect hood performance as the wall itself functions to capture fumes at the back edge of the hood.

And, definitely be aware of the head bumping issue. Capture area is great, but not at the expense of constantly cursing as you bang your head into the hood when trying to see into a pot on a back burner.

Bumping out a hood by three inches introduces a few other problems, like in an installation like mine, how do the sides of the top filler get trimmed? The front of would have a ledge there were the trim held back flush to the cabinet front. Another greasy, dusty ledge. If the filler is kept to its intended relationship with the hood, then there are side gaps that would need filling. It's a can of worms.
Constant cursing is good if you have a swear jar to fill.
Casey

Casey: sorry, I can't really follow what you are describing. As I said, it only works in certain settings.

Here'a a photo of our install:

You can see that the back of the hood is bumped away from the wall, in our case by about 1.5''. It's integral to the design of our hood surround, but it does function as well to move our capture area out further forward.

If your upper cabinets haven't been ordered, you could order 15" deep cabinets for the run above the range, rather than standard 12" deep cabinets. That way, pulling a 24" hood out 3" from the back wall would line up perfectly with the 15" deep cabinet fronts. You'd still need to put a 3" filler strip between the back wall and the back of the hood, but that's easily accomplished. I did this in my kitchen because all of my counters are 30" deep and uppers are 15" deep. I love the extra counter space and having deeper uppers means that extra large plates or other large items fit without any problem. I installed a Vent-A-Hood 9" tall X 24" deep X 48" wide range hood. The hood extends out 27" from the back wall with a 3" stainless steel filler strip installed behind the hood.

Sorry, I can't remember how to post a photo on GardenWeb (I tried), or I'd be able to post an image.