Return to the Appliances Forum | Post a Follow-Up

Is there any reason to do vertical venting?

Posted by eldiba (My Page) on
Fri, Mar 1, 13 at 20:12

After 105 years of being range-hood-less, our kitchen will finally being seeing its first vent hood in the near future. Our home is one storey with an attic. Our range (electric) will be located on an external wall. The hoods we are considering have the option for vertical venting with either round or rectangular ducting, or horizontal venting with rectangular ducting only.

Is there any reason we should vent vertically through the attic instead of going horizontally right out the back? I have heard that round ducting is preferable to rectangular, but is there any reason to do vertical (with round) when the horizontal option (with rectangular) would be *many* times shorter? Thanks!

This post was edited by eldiba on Fri, Mar 1, 13 at 20:13

Follow-Up Postings:

RE: Is there any reason to do vertical venting?

Shorter is better except....

If the fan is external, than a longer route may allow a silencer to be placed in between fan and hood reducing some noise.

If the area of the circular duct is significantly larger than the area of the rectangular duct, then pressure loss may be lower with the longer path.

A roof mount may keep the exhaust away from where it isn't wanted.

Many other factors relating to installation ease come into play, so there is no really simple answer.


RE: Is there any reason to do vertical venting?

Everything kas said is an excellent answer to the question you posted.

But ...

I wonder if you meant to ask a different question?. Maybe something more along these lines:

"We are buying a regular range hood to mount on an outside wall in our kitchen. It has rectangular 3" x 10" ports. Installation will be much simpler and much less expensive for us if we vent straight out the back with a rectangular duct through the outside wall. I've heard that round ducting is preferable to rectangular. With this kind of hood, will there be any performance gain if we use the vertical port and coupler and run 6" diameter round duct vertically through the roof?"

The answer: no. The rear vent will give you the best venting performance.

Will there times when you might want to do things differently? Sure, but you won't be doing them for better venting. You will be serving some other objective, such as noise reduction, as Kas mentioned. In those cases, you will be trading some venting performance for something else.

So, going straight out the back seems like the best solution for you.

RE: Is there any reason to do vertical venting?

Current kitchen (soon to be redone) has vertical, rectangular venting as it offered a more shallow vent box (3" depth x 24" length) behind cooktop upper cabinets which then turns 45 or 90 degrees. Round duct is preferable for less effluent in nooks and crannies, amongst other if you're starting from scratch but we aren't.

 o Post a Follow-Up

Please Note: Only registered members are able to post messages to this forum.

    If you are a member, please log in.

    If you aren't yet a member, join now!

Return to the Appliances Forum

Information about Posting

  • You must be logged in to post a message. Once you are logged in, a posting window will appear at the bottom of the messages. If you are not a member, please register for an account.
  • Please review our Rules of Play before posting.
  • Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review your post, make changes and upload photos.
  • After posting your message, you may need to refresh the forum page in order to see it.
  • Before posting copyrighted material, please read about Copyright and Fair Use.
  • We have a strict no-advertising policy!
  • If you would like to practice posting or uploading photos, please visit our Test forum.
  • If you need assistance, please Contact Us and we will be happy to help.

Learn more about in-text links on this page here