1

I'm trying to finish an en-suite bed/bath that currently has a capped 8" rigid duct coming off the main trunk. What is the proper method to supply air to both the bedroom and bathroom?

The bedroom is about 135 sq-ft and the bathroom is about 35 sq-ft. Can I just split the 8" rigid into two 6" flex? Or do I need to come off the trunk line with two 6" lines, one for the bedroom and one for the bath?

Thanks in advance!

  • 1
    Hard to say without knowing more about your HVAC system and home. Are the other rooms fed with discrete 8" ducts? – isherwood Nov 6 '19 at 21:19
  • 2
    Definitely use flex only where necessary. It adds quite a bit of resistance to the line. Semi-rigid is better than the light foil stuff, and rigid isn't that difficult to work with anyway. – isherwood Nov 6 '19 at 21:20
  • We need to know: HVAC system size in Tons, size of each return and their location(s), room sizes, size of all branches/outlets to give you a reasonable answer. Do you know why that rigid was capped? – peinal Nov 6 '19 at 21:48
  • Hello, and welcome to Home Improvement. We'll need to know more info before we can help. And, props for taking our tour before posting; few newbies do. – Daniel Griscom Nov 6 '19 at 22:00
  • Is there a reason using rigid ducting for the branches isn't an option? – ThreePhaseEel Nov 7 '19 at 1:03
2

Yes splitting an 8” duct to 2 separate 6” ducts is an appropriate size transition, since it is a master the air will be going to the same areas while the bathroom door is open. I usually add dampers to all my vents it costs more but makes balancing easier.

| improve this answer | |

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.