drain vent under cold roof?
The cold roof we are installing consists of blown insulation on a conventional room ceiling which hangs on ordinary joists. The joists are covered with cdx. Above that are 2×6 stringers which run from eve to peak. They form galleries which are vented from the soffit and the peak. Riding on the stringers is another layer of cdx and a steel weather roof.
In a effort to avoid unnecessary holes in the weather roof, I would like to vent my plumbing drains in these galleries rather than bring the vents up through the roof. I hesitate because I am not sure methane gas will vent properly.
Would anybody care to opine on this question?
Its illegal. At least your plumbing inspector will not pass it.
OTH, I don't think it is a good idea, even if allowed. Depending on your location and what you vent is venting at any particular moment, you will cause your cold roof to warm, and then freeze.
If your local code allows (and not all do, so check) you may consider venting out the gable near the ridge, if your construction allows. This has drawbacks, too, and depending on the specifics can look like krap.
As Tim said.
Remember that there a several million roofs in the US with "holes" in them. Leaks are rare, if done with some care.
Remember Mary Dyer, a Christian Martyr (Thank you, Puritans)
May your whole life become a response to the truth that you've always been loved, you are loved and you always will be loved" Rob Bell, Nooma, "Bullhorn"
Don't do it, as others have said.
Now. You don't say where you are. If you don't have plumbing/building inspection AND you live in an extremely dry location somewhere in the west, you could probably do it without a condensation problem in the attic space as long as the space is also otherwise well vented.
I have and old house in southern Colorado that had the bath vent blowing from right above the only shower to right against the old 1x roof sheathing. It had been that way for many years before I accessed the area while remodeling. There wasn't a sign of a moisture problem.
While a good idea in concept, I would not vent anything into a cavity of the home, including Radon (a lot of guys do a passive system and dont cut thru the roof to save on the penetration) and bath exhaust fans (I just fixed 2 last week that were venting into a soffit which most codes do not allow)
I would not even consider sewer vent anywhere other than thru the roof.
(unless using a studor vent but only use a studor if necessary)
You guys have humbled me, completely convinced me to be good. I'll run the vents through the roof.I'm reminded of great moments in building from the magazine. When I posted the inquiry I had, in a fit of enthusiasm, already cut off the offending vent pipes. What, me worry?Now I'm faced with correcting the damage, which, of course, will be no sweat.Tim, rjw, husbandman, and JeffinPA; thanks.BTW, JeffinPA, the house in question is half way up the mountain west of Lyons, Co.Eno Compton
Greetings from PA Eno.
Have fun with your project.