Proper drain and vent help needed

**papisox** · 10-30-2010, 09:30 PM

Hello,
I'm renovating my 2nd floor bathroom and taking out all the old plumbing and redoing everything. I wanted to make sure i am doing it correctly and using proper tees and wyes etc. Please see pic below. Main pipe to septic is 4", which goes to 3" in bsmt, then up to 2nd floor bath. Sink on main level drains directly to 4" and has no vent. See in pic where 3" comes up from bsmt, I need to know proper way to tie in wc, bath, and 2 sinks, with vent and drain. I'm hoping to make 90 from 3" coming from bsmt, feed the 3 fixtures and then switch to 2" after toilet and up outside wall, then 45 up to existing hole in roof. Is this feasible, and how? I'm in ontario, canada. Thanks for the help.

hj · 10-31-2010, 07:25 AM

You need a much BETTER diagram if you intend to show ALL the waste and vent piping. Do NOT believe the DIY shows and Home Depot when they say, "Anyone can do plumbing. All you need is a can of glue and a pipe cutter."

**papisox** · 10-31-2010, 06:26 PM

can you recommend some cheap or free software to do this to lay it out? Please let me know. thanks

**cacher_chick** · 10-31-2010, 06:48 PM

There is no need for software. You should study the plumbing code which covers your locale. The building inspector will want to see an isometric drawing. Google for some examples and you will likely get some insight. A good part of the learning curve is knowing what type of fittings to use in each location/situation.

**Terry** · 10-31-2010, 07:19 PM

Here is a nice link to Bert Polk's plumbing tips

**papisox** · 11-01-2010, 07:29 AM

I think i've got a good grip on it, my main concern is if I can just run the 3" drain teeing off for the sink and bath, then going to toilet and venting AFTER toilet. WIll this be ok?

**cacher_chick** · 11-01-2010, 02:49 PM

Generally speaking, every trap must have it's own vent. In some locations the toilet can be wet vented through the lavatory vent.
In a horizontal drain, the vent will be downstream of the trap.

If you were to post an isometric drawing of what you intend to do, then it would be easier to judge it's correctness.

**papisox** · 11-01-2010, 03:27 PM

please see attahched, does that work as a drawing?. they had vent upstream of fixtures, but i don't believe that works. I can't have vent through attic floor as that is living space. Can I bring vent up to attic floor, then do 90' and up and out through roof deck? Just not sure how to tie everything in.

**papisox** · 11-01-2010, 03:27 PM

also kitchen sink has no vent as of now?

**dlarrivee** · 11-01-2010, 04:32 PM

That is not isometric...

Like posted above, EVERY trap must have its own vent.

But if you're going to wet vent a bathroom group you're going to have to tie the w/c in furthest downstream, not the other way around.

**papisox** · 11-01-2010, 08:02 PM

The drawing above is how it is presently(or was), I am trying to see how to do it properly. I realize the wc must be furthest downstream and each fixture needs its own vent, i just don't see how I can do it the way the vent presently goes out behind wc. Only way I can think of is the extend 3" pipe from bsmt up to attic floor, then 90 it out to outside wall and up through roof. If I made the vent go straight up like that would I be ok? And then extend each fixture vertically with a sanitary tee and connect to the vent that way? Can you explain a little more what isometric is? I found a couple examples online and it seems like thats how they were as I drew? Thanks for the help