42x27 ventahood, 900 (600 actual) cfm. It's enough for anything but wok cooking on the front burner, when it comes up a bit short. That may relate however to our longish duct run, which means we don't get the full cfm.

Not knowing how long your duct run is or the number of turns in it, it is a little hard to say but as a guess I would think it is a little small. I can tell you from experience it is better to have one larger than what you need and not run it on full speed than to have something that is too small and listen to your smoke alarms going off. In most cases considering the amount of money you are spending on your kitchen a few hundred dollars more is a good investment and you will be happier in the long run.

I think it's nuts to go with a liner that's narrower than your range! Totally bogus recommendation from your sales folks. If you have a 42'' hood surround then go for the largest liner you can get in there, as anything less than a 42'' liner is already less than ideal. Going narrower than the range is just silly. See any of kaseki's posts on hoods to understand better the concept of lateral diffusion of smoke and the need for adequate capture area.

We have a 42'' 600 cfm VAH liner at our lake house. I hate it. It is NOT adequate even for our rather modest 36'' Dacor PGM cooktop. Last weekend I was searing some pork tenderloins while holding a sheet pan up to steer smoke back under the hood. Forget the "900 cfm" equivalent nonsense that VAH sells. For a real kick-a^% range like a BS I think it would really fall short.

Me: I love our new Modern Aire liner. They can customize it to fit your surround. Couple it with a high cfm remote blower and then you can really cook.

yikes. i hope some other people post and assuage my concerns. xox

That seems too small and not powerful enough to me. We have a 42" x 24" Independent hood (its either 1200 or 1400 cfm - can't recall the exact number) and it works well over our 36" Bluestar.

A 34" insert over a 36" range when you actually HAVE the room to go bigger is telling me your salesperson (a) is ignorant of basic exhaust guidelines, and/or (b) has extra inventory of the 34" insert that he/she is trying to unload. The basic guideline is to go 3" wider on either side of your range if you can. If you don't have the space for the extra inches, then at least have the same width as your cooktop. I would also have at least 900 cfm's. As to saving money, I would be interested to know how much more $ a wider insert would be - I bet it's not much as a percentage of your kitchen re-do, and would really make the exhaust work properly.

It always kills me when someone wants to "make do" with a smaller width or less cfm's to save money. Meanwhile, what they spend on their inadequate exhaust is like throwing money out the window, since it will never work efficiently. It would be better to spend the extra money and get something that works.

Also, I am wondering how deep (i.e. front to back) your hood will be. There are many on this forum who wish they'd gone deeper, as their front burners aren't covered enough by the hood to utilize the exhaust. Please let us know.

It depends on how you cook. We have a 30" x 27" 300 CFM Vent-A-Hood* over our 24" BlueStar range. The hood completely covers all four burners, with a 3" overhang on the sides. It works fine for us, but we don't do screaming hot sautés and stir fries with billowing clouds of smoke.

I ran a series of experiments several years ago that convinced me that coverage is the main issue in specifying a vent hood. Increasing the blower capacity to compensate for inadequate coverage is wasteful, doesn't work very well, and can cause makeup air issues.

* Because of structural issues in our 93 year old building, our choices were a 36" total length 6" vent with one bend or an 18' total length 8" vent with three bends. A very good architect and a very good structural engineer confirmed my assessment that there was no way to get anything larger in cross section that a 6" round pipe through the wall next to the range without moving the main waste stack that serves plumbing fixtures on three floors. We chose the shorter run.

ack!!! my most previous post was actually me trying to email the thread to my husband!!! too early in the morning and before my coffee, i guess. those "hugs and kisses" were for him, but I thank you all so much for your valuable feedback. I'm so embarassed!

The model they steered us towards was the Prestige UIB34-SI which is 34"W x 15"D x 14"H and 600 CFMs.

The next step up is the 40" insert that has the same D and H, but 1200 cfms. It's about $600 more expensive. and they said we'd need a transition to a 10" duct.

Here's the layout of our kitchen. The range is located on an inside wall, but the sink is on the external wall and that's how the hood will vent out. Hope that makes sense.

Thanks again for the feedback.... I really appreciate it.

j.

Based on your description of the way your husband like to cook, a 15" deep insert in a cabinet is not going to work very well no matter how wide it is.

I do not know if I can assuage your fears but here are some thoughts. xox

Many comments here are making it sound like you are putting in a hood that is narrower than the range. But you are not, you are putting in a narrower LINER. So a lot depends on what the actual capture area is that is being built.

Am I correct that your "cabinet" is a mantel style hood? If so, then I imagine the insert is going to be tucked up in there quite a bit and your width should be just fine. I would be more concerned about the depth, as velodoug said. Based on your layout, the hood only about half covers your front (22K!) burners and I think that is a mistake.

My "guess" is that the depth is going to be more of an issue than the CFMs, but both could stand being bumped up.

Ya Think is correct think more about depth and width of your cabinetry.

For the difference in the cost i would recommend the UIBTF40OWC15. including a 1200cfm blower for $1615 this is a far better designed insert.

The UIB34S1 normally sells for $1035 the UIB40S2 sells for $1615

Provided you are putting the insert up inside the cabinet by at least 4" you could go for a UIB34S2 that will give you 1200cfm for the same size at a cost of $1455

i think the key here is not the size of the insert but the size of the capture area you build with your cabinetry. Always make sure the insert in not flush with the lower edge of the cabinetry but recessed inside the cabinetry. I explain to my customers an insert is like and inverted sink a small hole but all the water goes down the plug, its the same with an insert it maybe a small insert but if its recessed correctly any smoke you capture with in your cabinetry will get sucked into the insert and blown out of the house.

Trevor's point is well taken and sounds like he's got great suggestions for much improved ventilation at modest extra cost. But...to restate, a liner that is narrower than the range, and only 15'' deep is way short of adequate.

Trevor and ya think point out that the hood surround itself can function as the actual capture area, with the liner acting more as the conduit out for the smoke. That's only partially true.

First, realize that the vertical walls of the hood liner will create "dead spaces" inside the hood surround but outside the walls of the liner. For these areas to be vented out, smoke would have to be drawn first downwards to clear the bottom of the liner, then back up through the duct. Since smoke etc naturally want to rise, that's asking a lot and I think you'll find stagnant air and fumes in those areas.

More importantly, the area inside the surround not covered by the liner will have no baffles or filters to collect grease. The result is over time there will be a truly yucky buildup of grease and nastiness in the areas of the hood surround not covered by the liner. These will be next to impossible to reach to clean, and if it's a wood liner, it will never come fully clean anyway. Bleah!

I'll say it again: if you are going to do a custom hood surround, far and away the best option is to get a custom hood liner that will fit as close to flush with the surround as is possible. I'd also insist on a surround that is at least 24'' deep, as 15'' is just too shallow to be effective. Several companies dedicated to hood production can do exactly that, it's what we did with Modern Aire and is I think the optimal solution.

clinresga - I would have to see a wind tunnel type test in order to intelligently critique your dead space hypothesis, but it does sound at least plausible. However, I would only expect to see that affect to an appreciable degree at higher fan speeds where you are really creating a "funnel" of air. Now assuming that you turn on the hood BEFORE it is needed (as you should), then following your theory that dead space will be filled with ambient room air and the smoke will bypass it. Anything that does get caught up in the corners would easily be flushed out at a lower speed at the end of cooking. On a far more extreme scale, think of a bathroom fan - it ends up clearing the steam accummulated across the whole ceiling, not just a tube of air between the door or window and the fan.

In short, my guess (again, stressing "guess") would be that this is a negligible concern.

As for the grimy hood, I completely agree. I would line at minimum the top section with stainless. Whole surround, even better.

All that aside, if she has the option of changing her order I would have to believe that she would be better off with a bigger insert and more CFMs. I know I would rather be safe than sorry.

Thank you again to everyone. I'm reading your posts with such interest and am going to print them for DH for discussion tonight.

I'm worried that we've already put the deposit down so may not have huge flexibility (if any, oh dear) but it would seem that if we "upgrade" within the prestige line that would be the easiest to push for... That said, I'm looking now and their inserts only come in three depths: 12", 15", and 18". I'm not disputing what you're all advising- as it makes perfect sense-- but I'm just wondering how a reputable(?) hood company would only make those depths knowing that most ranges would be deeper. Fair question?

Thanks again so much for your expertise on this!

ya think: as usual you and I end up pretty much totally in agreement. I agree there is some midground behind my dead space versus airflow argument. Otherwise we're totally in agreement.

julia: are you sure we're talking about the same thing? What I and I think others have assumed when you said the hood was 15'' deep is that it extended out from the wall horizontally only 15''. I can't conceive of a hood that has a depth of only 12''!

Are you using "depth" to mean the vertical height of the liner--i.e. the distance from the bottom of the liner to the top? If so, that's not what I and others have been concerned about. We are all worried that your hood does not extend out far enough from the wall to cover the front burners. The standard for that is 24'' and some will choose an even deeper 27'' hood to maximize effectiveness, although it can lead to tall folks bumping their heads.

However, since you said the hood was 15'' deep and 14'' high, maybe you really are looking at an incredibly shallow hood. And a 12'' hood--that would be the strangest looking thing I've ever heard of. Even a MW/vent unit extends more than a foot out.

At any rate, a bad idea if it's really that shallow.

Hm. well I hope I was reading it wrong and actually the specification guide makes it seem like maybe I was... Here are the details. The model we have made the deposit on is UIB34-SI. i can't thank you all enough...

OK, I looked at your plans. I guess the hood liner you are considering would be an undercabinet unit which does not protrude past the front of the adjacent cabs. If at all possible I'd substitute either a freestanding hood, or a redesigned hood surround that does indeed come out at least 24'' to cover the front burners. That may seem a bit doctrinaire, but if you're taking the leap to an ultra-high BTU BlueStar range, then it makes no sense to match a "pro grade" range to a low end "builder grade" hood design. Do a 42'' wide, 24'' deep hood from a good manufacturer.