Based on our 600 cfm VAH hood at our lake house, I'd say it's not a bad unit, but no one would call it quiet. We do a fair amount of "smoky" cooking and run it on high quite frequently. On high, with both blowers going, you have to raise your voice to converse near the hood. On "medium" (one fan running on the high setting) it's still a somewhat annoying (to me) background sound, on "low" it's pretty reasonable. I think if quiet is really the issue, then there is no question that an external roof or wall mounted blower, coupled with a Fantech silencer mounted in the attic, is clearly the best. That's what we're doing for our ongoing kitchen redo in the main house. Next best would be an remote blower mounted in the attic, again ideally with the Fantech silencer. Worst is any in-hood blower. But...edlakin is right, most of the time you run a blower on low settings so this is not a big deal unless you're really obsessive.

Hi- hope this is the right forum to post this in... it doesn't say HVAC in the title but it's the closest mach- also posted in Appliances... We're installing a 600 CFM range hood in a one-story ranch house in southern Maine. The guy at the appliance store was saying something about "if you can afford it, get one of those chef-hat type spinning roof caps". He thought that the lower-profile ones might cause ice dams because they spit the hot air right onto the roof... and/or that snow on the shallow roof pitch (5:12) might cover and block the low-profile type. Is he being overly cautious? Clearly we want our vent to work as optimally as possible and avoid roof leaks, but we're also on a budget (and DIY.) Related question: what type of damper is best and where to install it? I have read to install it at the thermal break, i.e. at the attic insulation level. Comments on that? Thank you!! STacey

I only saw one Ventahood where I could try to figure out if the cleaning or the more raw underside would bother me, and it was not connected to power so I don't know about their sound level. I've heard they are quieter and I've heard they are louder. I think the looks of the cages vs baffles would be more of an issue for me. While I was trying to decide whether that was a bit "raw" looking, I was led to a guy at the place where I bought my appliances who said he'd seen and heard both side by side. He said the Best by Broan was better for sound and operation, so I went with it. Very scientific, huh? Unfortunately, buying a vent is like that. I have a 1200 cfm model with an external blower and got the baffles. The blower sits just above my sink on the opposite side of my kitchen (better than the toilet or shower straight above --LOL) and it is quiet when you are outside. I'm not sure that in my set up the remote blower made that much difference. If I'd have another inch or two, I'd have been able to put in a silencer. Most of the time, I run the vent on the lowest setting or up to about 1/3 power -- rarely over 1/2. At that level, the fan on my ovens is as loud. You barely hear it away from the vent, but you will standing right under it. At full power, you will hear it, but even then it is not as loud as the ineffective downdraft my last cooktop had -- with only one speed. If you turn it on when you first start cooking and run it higher for things like fish, popcorn, bacon, you will not smell them all over the house. I made 120 bags of popcorn, both on the stovetop and in the microwave (bags opened under the vent)one afternoon. I delivered them to the school, came home and could not smell any popcorn. Maybe it could be more perfect, but I'm happy with my choice.

First, the ducting has to be steel so care is needed to assure that any flexible ducting is the correct material. You can make a duct path as tortuous as you want, so long as the blower being used is capable of the necessary flow rate at the pressure loss you have incurred. Generally, the baffles or mesh filters dominate the pressure loss so a short length of bends is not too critical. Consider an angled duct path in the wall with two 45-degree bends. What size duct is in play here?