Flat venting?

[BMWpowere36m3]

I just want to verify what actually is flat venting. Below are a few models showing a basic drain, p-trap, trap arm, vent arrangement. Which are considered flat vents?

First up is what I think (based on forum comments) is the preferred "method" of venting, horizontal trap arm into a sanitee and the waste goes down and vent up.


Vertical

What if your horizontal trap arm connects to a horizontal waste line and there is no vertical drop... you put in a wye or sanitee (on its back) and vent straight up off the horizontal trap arm. Is this a flat vent?


Vertical, but should be a wye on it's back, not a santee

If the above is okay... then the below should be okay as well. Sanitee or wye rolled up at least 45 deg (considered vertical).


45 degrees is vertical, but should be a wye on it's back.

What if you put the sanitee or wye exactly horizontal is it a flat vent? And/or an issue because you are not locating the vent opening above the centerline of the waste line?


This is flat.

Or is the last one a flat vent because the vent line goes horizontal before being 42" off the floor or 6" above the flood rim level of a fixture..


This is also flat when it is no longer at a 45
Any fitting on the horizontal should be a wye or combo.

 

[hj]

I am confused. Are you asking the questions and then making the correct response to them, or is this someone editing a previous post?

 

[Sponsor]

 

[BMWpowere36m3]

I dunno… it seems someone edited my posts? I wish it was a response and not an edit to my posts, but I appreciate the response by whomever.

As far as the sanitee… I thought it was considered okay for venting, but not when connecting a vertical WASTE line to a horizontal one.

 

[Cacher_Chick]

The vent cannot contain liquid or hold waste, which is why it must be vertical. A flat vent is a vent that is horizontal and below the minimum allowed height. Any angle greater than 45 degrees is considered vertical.

 

[hj]

ANY fitting within the range of becoming a "flow line", meaning below the overflow level of a fixture is required to be considered a drain and follow the requirements of a drain, therefore, a sanitary tee is NOT a suitable fitting for connecting a vent to a horizontal line, in most areas.

 

[BMWpowere36m3]

ANY fitting within the range of becoming a "flow line", meaning below the overflow level of a fixture is required to be considered a drain and follow the requirements of a drain, therefore, a sanitary tee is NOT a suitable fitting for connecting a vent to a horizontal line, in most areas.

Can you also not use a vent 90 till your above the flood rim level of a fixture?

 

[Terry]

Can you also not use a vent 90 till your above the flood rim level of a fixture?

All fittings below the flood level need to be properly located waste fittings.
"Vent" fittings can only be used where there is no possiblity of water being in them.
For that reason, I don't even carry them on the truck.

 

[hj]

IN fact, true "vent fittings", are used so rarely, that they often cost more than a similar "drain fitting".

 

[BMWpowere36m3]

Thanks guys!

 

[Tom Sawyer]

A horizontal sanitary tee, with the branch in the vertical position and not receiving waste from fixtures above can most certainly be used for venting and both the IPC and the UPC even show pictorial examples of it being used in. That fashion.

 

[Asktom]

Below the flood level, the UPC most certainly does NOT allow a san tee on its back to be used as a vent, a drainage fitting (wye/combination) must be used. UPC 905.3 "... Vents less than six (6) inches (152 mm) above the flood rim level of the fixture shall be installed with approved drainage fittings, material and grade to the drain." As for the IPC, I don't know.