View Full Version : Moving WC ... stack thru roof location
06-20-2011, 05:36 PM
I'm moving the WC to a location across the room (approx. 8 ft from current location.
Sink will also move across the bathroom next to WC.
Shower will remain and washing machine also accesses drain and supply from other side of original wall.
If I can avoid moving it I'd like to keep the location the same where the soil stack goes through the roof.
In order to do this I would bring the soil stack up the new wall behind the WC and angle over to meet the current stack. This would leave the current stack in place to accommodate venting the shower and washing machine drains, the original WC opening would be capped.
Vent stack for relocated sink would tee into new soil stack 49" above the flood level of WC.
Capacity will not change, just the venting will be redistributed and exit the roof via the original 4" soil stack.
Is there any problem running my new soil stack up and angling over to meet the original soil stack?
Thanks for any help you can provide.
06-20-2011, 05:56 PM
As long as you follow the rules (proper fitting, proper height, proper slope), you can run the vent anywhere you want. The vent must have a slope downwards to prevent condensation or a backup from pooling or plugging the line. This allows it to also drain down into the sewer, regardless of what may happen (rain, snow melt, whatever that could get in from the top).
06-20-2011, 06:17 PM
Thank You Jadnashua,
I will slope the soil stack ~30 degrees so there will be no problem there.
My biggest problem will be tapping into the soil drain below, I haven't looked at it lately but will try to just re-route the soil drain from new to part way up the existing soil drain being sure to incorporate all existing drains and stacks. I have a book with codes on the way so that should be helpful as well.
Thanks for answering my question, I thought I knew the answer but wanted to run the scenario by you first.
06-20-2011, 06:30 PM
I guess I should clarify that I will leave the original soil drain in place and just cap the original WC connection. New soil drain will Tee or Wye into existing soil drain a couple of feet up from the base the drain.
I will need to do this rather than just re-routing so that rain, snow etc will have a way to drain down the original soil stack and into the septic/ sewer.
IT sounds like a pretty ambitious project for a DIYer. KNOWING how to do it, and actually doing it that way can sometimes be two entirely different things.
06-20-2011, 06:38 PM
the vent takeoff locations and sizes on drains all have to be within certain bounds as to their location as well. 30-degrees isn't required...all it needs is a minimum of 1/4"/foot (about 2-degrees), just like a 'normal' drain, but more won't hurt. It may mean it's harder to get it into the wall as it would cross more studs. So, you can tone down that slope some to make life easier.
06-20-2011, 09:19 PM
The slope will be within Attic space, you're right, there is really no reason for a steep slope and a slope as you suggest (1/4" per foot) allows me to use standard 90 deg. fittings so I'll go that route or slightly steeper.
Your answer comes across as a tad bit condescending, perhaps it wasn't meant that way or perhaps it's in your nature as a moderator to weed out the turnips. At any rate, I agree, that this is an ambitious project and the fact that it's only part of a much larger project is ironic. I'm also removing a fiberglass tub/ shower combo and replacing it with a barrier free tile shower with all new SS fixtures, tiling the bathroom floor and relocating a wall to expand the bathroom. That wall will become one wall of my new walk-in closet walls which, of course requires another wall section to be removed which accesses the master bedroom. Then next week I'll be starting a new project ... ;) just kidding ... this one will keep me busy for a while.