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jsceva

Noise from roof-mounted blower? How bad is it?

jsceva
12 years ago

Can anyone on the board who has an external blower for their range hood comment on the noise level near the blower itself? Not in the kitchen where the hood is, but in the room below where the blower is mounted, with or without a window open.

We think we have figured out a way to vent to the roof, running the duct up an external wall, but there are two floors of residents above us...the blower would essentially be mounted directly above the ceiling of our upstairs neighbor. I am worried it will be a problem, but can't find any solid information on what to expect.

Any real world experiences would be greatly appreciated. I know it will depend on brand, but any information is better than none..

Comments (6)

  • weedmeister
    12 years ago

    This isn't an answer, but how can you do this? I assume you do not own the building if you have upstairs neighbors?

  • jsceva
    Original Author
    12 years ago

    It's a small condo building...I own my unit, and a 1/5 undivided common interest in the building. Requires majority approval (me + 2 others saying "yes"), but since there are so few of us it is doable.

  • amcook
    12 years ago

    I have a 1600 CFM rooftop blower and I can say noise just outside my kitchen is considerable when it's at full blast. How much noise you get inside right below it would depend a lot on the specific layout, insulation, and countless other factors. If it really is directly above the ceiling, I think there would be some noise even with the windows closed. It might not be an issue if it's above their kitchen but if it's above their bedroom or living room then there will probably be some problems. Your best option is to use an internal blower which would reduce the vibration noise on the room. Frankly, in a multi tenant building, there's going to be some noise from the other units anyways so hopefully your neighbors will understand that. You could always work out a curfew with the people above you and promise not to use the vent between the hours of 9pm to 10am for instance.

    Good luck.

  • clinresga
    12 years ago

    We have a 1400 cfm Fantech remote blower mounted in our attic, where it then vents through the roof. Not exactly what you are doing but I can give you a run down on the noise levels:

    In the kitchen, incredibly quiet. I won't resurrect my old posts where I measured decibel levels at the hood, compared to my much hated Vent-a-Hood at our lake house. Suffice it to say that it is incredibly quiet even running at full bore.

    Our ductwork then runs up through a wall in a guest bedroom. This room is essentially directly below the blower in the attic. If the hood is running full speed, there is a combination of airflow and the blower noise. It's moderately loud--significantly louder than the airflow through the ducts when the A/C kicks in. Maybe on the order of a box window fan running on low speed, but it's white noise so not too annoying. However, it's loud enough that a not-too-friendly neighbor might complain.

    And finally, outside the house: if I stand in the yard directly below the roof vent, with the blower running full speed, it's pretty noticeable. I'd say it's almost as loud as one of our HVAC compressors running outside the house. Again, it's white noise and if neighbors don't complain about our HVAC, they wouldn't complain about the vent either.

    So... my worry would not be the noise outside the house, but rather inside if a duct was running directly against a wall. However, if you are running the duct externally, that would be much better than us, since our duct runs inside the actual wall cavity. If you are on relatively friendly terms with neighbor, and you don't expect to use the hood for many hours a day, I suspect you'll be OK.

  • jsceva
    Original Author
    12 years ago

    Thanks for the feedback, everyone...as tempting as a more powerful blower is, I think we have decided to just stick with an internal blower so the noise primarily impacts us, rather than neighbors....its just not worth the risk of future hassles to do otherwise. Even if the current owners are cool, who knows who will move in in the future.

  • billy_g
    12 years ago

    We have a 1400 CFM Abbaka blower mounted on the roof just above our master bedroom. The duct is in the wall between our bedroom and closet. First, we're rarely in our bedroom when the blower is running, but even then we hear very little noise. I surrounded the duct with rockwool before the drywall went up, and we have a ton of insulation at the roof (closed cell spray foam plus dense-packed fiberglass Spider insulation.

    It's not a problem for us. The Abbaka blower is quieter than the blowers from Broan and othes, so this helps.

    Billy