Two bathroom groups, is this correct?

Users who are viewing this thread


New Member
Reaction score
I am renovating my home by adding back-to-back bathrooms on the second floor. I have asked a plumber to do the plumbing. He came one afternoon and then he disappeared (after the first payment), and now I cannot find him :( . I am thinking to finish the job myself but I am worrying that he may have done something wrong. The attached diagram/pictures shows the current plumbing.

1- He used "wet vent" for the 2 bathroom groups: and said toilets must be the last fixtures, but since "Lav1" will have its own vent , this would not be a code violation to have lav1's connection after Toilet2, is that correct?
2-For the "Horizontal to vertical" on one branch he used a regular 90-degree elbow, and for the other branch he used a long sweep elbow, Both branches are connected to 3" Wye in the vertical waste line. I asked him about the regular 90 degree and he said since it is used for horizontal to vertical, it is ok, I am wondering if that is correct for Wet venting/double toilet as well?
3- To make the toilets be the last fixtures, he has used a 7ft pipe for Toilet2, is that ok or any limit on its length?

Any help is highly appreciated, thanks.


  • plumbing_diagram.png
    36.7 KB · Views: 109
  • 20220123_111848.jpg
    88 KB · Views: 111
  • 20220123_114149.jpg
    100.3 KB · Views: 106
  • 20220128_082441.jpg
    64.8 KB · Views: 106
  • 20220123_111740.jpg
    100.3 KB · Views: 115


In the Trades
Reaction score
Berkeley, CA
I'm more familiar with US codes than Canadian, but here are some partial answers:

1) That may depend on the wording of the wet vent rules in your code. If the rule is no non-WC wet vented fixture can occur after the WC (which makes sense to me), then your layout complies. This issue doesn't arise under the US codes,, as one code (UPC) only allows one bathroom group (so there's at most one WC, which has to be the last wet vented fixture), and the other (IPC) doesn't require the WC to be last.

2) Yes, extra sweep is not required for horizontal to vertical, and the wet venting aspect of the install shouldn't change that.

3) You'd have to check your Canadian code, one US code (UPC) limits it to 6', the other (IPC) has no limit.

Cheers, Wayne
Hey, wait a minute.

This is awkward, but...

It looks like you're using an ad blocker. We get it, but (1) can't live without ads, and (2) ad blockers can cause issues with videos and comments. If you'd like to support the site, please allow ads.

If any particular ad is your REASON for blocking ads, please let us know. We might be able to do something about it. Thanks.
I've Disabled AdBlock    No Thanks