dwv pipe through roof

[daniel nantell]

I know you have to have at least one dwv pipe vented throught the roof, does that mean that the other dwv pipes can be vented to attic space ? thanks

[Brandon Whitmore]

No,

if allowed in your area, I take that to mean that you can use AAV's. You don't want to vent sewer gases into the attic.

In my state, AAV's/ mechanical vents are not allowed at all.

[A.D. Miller]

I know you have to have at least one dwv pipe vented throught the roof, does that mean that the other dwv pipes can be vented to attic space ? thanks

DN: In case you don't know what BW is referring to:

Air Admittance Valves (http://www.toolbase.org/Technology-Inventory/Plumbing/air-admittance-valves)

[Ron Hasil]

The pipes can go into the attic and tie into the vent that is going through the roof.

[Brandon Whitmore]

Ron,

I know of one plumber that no matter where the pipes come up into the attic, will tie them all together like that. It's for aesthetics, and to help prevent issues with leaks at the roof penetrations. Seems like a great idea-- some may call it a waste of pipe.