Vent pipe elbows

[bluedog225]

I’m getting a bid from a plumber to putin the waste lines for my workshop/cabin. I‘d like to run an idea by the plumber before he starts…well, I forgot to ask when he was on-site.

Can I put three 90 degree turns in a 2” dry vent pipe? This would allow me to run the vent where I’d like it to exit the roof.

I would think it’s ok since it’s just handling air. But thought you guys would know.

Thanks

 

[The Cobbler]

plumber should know , but I think it would be ok.

 

[PopcornSutton]

I think in many places a single 3" vent through the roof is all that is required. Vents should have grade on them.

 

[CraigStu]

Could you do what you want using 45deg vs 90deg? I don't really know much about this but I think I'd want to avoid any level sections of pvc so rain/debris could find it's way to the bottom.

 

[housewolf]

I’m getting a bid from a plumber to putin the waste lines for my workshop/cabin. I‘d like to run an idea by the plumber before he starts…well, I forgot to ask when he was on-site.

Can I put three 90 degree turns in a 2” dry vent pipe? This would allow me to run the vent where I’d like it to exit the roof.

I would think it’s ok since it’s just handling air. But thought you guys would know.

Thanks

If you are asking if there is a limit on 90 deg turns a vent can make before exiting the building, no. It’s fairly common practice to tie them together & run to the rear of the house in residential.

 

[manwithtools]

Just make sure you maintain a positive upward slope on any horizontal runs.

 

[HoosierBuddy]

I believe you are limited in the total number of feet your vent piping can be (consult your manual) and you have to add in "equivalent length" for all fittings used along with your straight sections, and compare that to the maximum allowed.

Engineering Toolbox reports a 2" 90-elbow has an equivalent length of 5.2 feet. So 3 of them would add 15.6 equivalent feet to your vent. Add that to your straight sections and compare to the spec.

 

[manwithtools]

I believe you are limited in the total number of feet your vent piping can be (consult your manual) and you have to add in "equivalent length" for all fittings used along with your straight sections, and compare that to the maximum allowed.

Engineering Toolbox reports a 2" 90-elbow has an equivalent length of 5.2 feet. So 3 of them would add 15.6 equivalent feet to your vent. Add that to your straight sections and compare to the spec.

I don't think he's talking about a vent for tankless water heater, if that's what you referring to. I think he's talking about a vent for the waste lines for his plumbing.

 

[bluedog225]

Thanks all. Yes, just the vent for the waste.

 

[manwithtools]

Thanks all. Yes, just the vent for the waste.

Then I think within reason you aren't limited in length of the vent other than a Max 5' horizontal run from any trap. As someone else mentioned, two 45 deg fitting separated by a few inches to accomplish the 90 deg turn is a less restrictive way to do it. Not sure it matters though. Your plumber can confirm. All horizontal runs dry vent should slope upward at 1" per foot.

 

[nadogail]

If you have a need to run a cable down the vent to clear the drain, those sharp 90 degree elbows might present a problem.

 

[The Cobbler]

^^^ vents aren't designed to be cleanouts.

 

[malibu101]

^^^ vents aren't designed to be cleanouts.

When the poop hits the fan, you stick it in anywhere you can.