Opinion please on back to back toilet fitting plumber used

I was hoping you all could give me an opinion of some plumbing work I am having done at the moment in Florida. Our bathrooms are back to back and we started will wall hung toilets. One side had a leak in the wall resulting in us tearing up the bathroom and floor to repair/replace the damage. We decided to get estimates on switching to floor plumbing/toilets while everything is opened up and currently have 2 issues that we feel need attention.

First was that a beam under the wall was cut into to accommodate the new cross. It was a 2x8 piece of wood and aprox 3 1/4 in was cut out. The worker that day said to us when we asked why he did that that it was fine and that so long as he didn't cut out 50% or more there was no need to brace it. I talked to the owner that said in a cost benefit analysis of cutting the bean vs connecting lower and having the expense of redoing tub drains it made more sense to cut the beam, but that he was told only 2 in were cut out by the worker. . .

Second issue is the type of fitting they installed. After the plumbing work was done I was reading the toilet manual that they left me after installing the toilet in the good bathroom opposite the torn up one. Its a toto toilet and very clearly on the first page it says not to use a cross fitting but a wye type fitting. It appears to me that they used a cross type fitting. I've been told that it's done to code and that I won't have problems with it but I read a lot of problems people are in fact having with cross type fittings and these newer high flush toilets.

My thought is that even if done to code the installation specs should be considered too which they clearly were not and that the cross fitting should be removed and replaced by what's indicated in the manual. We took the pipe cap off the torn up side and flushed the other side, the water completely filled the tube almost 14 inches across to the lower portion of the elbow. Even if bowl water level opposite doesn't drop it doesn't seem sanitary or correct that water would bypass the septic drain like that and go so far into the other toilets drain arm.

What do you all think? The owner is coming to look at the beam and discuss with me the fitting, I am trying to gain knowledge in the meantime. Thank you!!

Florida Building Code, Plumbing, 706.3 says that double sanitary tees cannot receive the discharge of water closets. There is an exception noted, that requires at least 18" of horizontal pipe between the water closet and the double sanitary tee. What you show in the picture definitely doesn't meet that criteria.

I couldn't find the section in the Building Code relating to notching of floor trusses, so I can't comment on that.

Thanks for the reply.

I looked up the code and it states "Back-to-back water closet connections to double sanitary
tees shall be permitted where the horizontal
developed length between the outlet of the water closet and
the connection to the double sanitary tee pattern is 18 inches or greater"

Discussing what developed length means with someone else I concluded that it would be the measurement of the solid orange line below which is just about 18 inches. Do you agree? I thought it did meet code but that it was still wrong . . .

I would definately have that beam braced. All those beams are load barring. And i agree with phisfood . I read up on the plumbing code

Florida Building Code (2010 Plumbing) 307.2 & 307.4 has a brief answer on cutting and notching framing, But Florida Building Code (2010 Residential) R502.1.5 & R502.1.5.1 should give you the answer on cutting or notching joist.

natalie559 said:

Thanks for the reply.

I looked up the code and it states "Back-to-back water closet connections to double sanitary
tees shall be permitted where the horizontal
developed length between the outlet of the water closet and
the connection to the double sanitary tee pattern is 18 inches or greater"

Discussing what developed length means with someone else I concluded that it would be the measurement of the solid orange line below which is just about 18 inches. Do you agree? I thought it did meet code but that it was still wrong . . .

Click to expand...

The solid orange line show the center-to-end measurement. The piping between the double sanitary and the 90 which includes the piping in both fitting should be your horizontal developed length if I'm not mistaken.

Thank you all!! Appreciate the reference to the building codes on the cutting of the joist- looking that up was really helpful in knowing for sure that they did do that incorrectly.

Plumber came by this am and looked at everything. His opinion was that the fitting was just fine and wouldn't cause me issues, said the water in that pipe wasn't anything to worry about. I disagree based on what I've read and said that given this great opportunity to do things better with the bathroom being opened up that I want the fitting that the manual states is the correct one. He said he would replace it to what I want and given the space the new fixture would need to be cut in lower (which if used in the first place would have avoided the cutting of the joist). Coming in lower will avoid any pipe in the joist space and a new 2x8 beam with be attached next to the one that was cut.

What confused me and I didn't have the knowledge to reply very much was that he said the double combination fixture wouldn't be to code. I don't understand how that would be. I looked up Fla code and this is what it states (see chart below),

"706.3 Installation of fittings.
Fittings shall be installed to guide sewage and waste in the
direction of flow. Change in direction shall be made by
fittings installed in accordance with
Table 706.3. Change in direction by combination fittings, side
inlets or increasers shall be installed in accordance with Table
706.3 based on the pattern of flow created by the fitting.
Double sanitary tee patterns shall not receive the discharge of
back-to-back water closets and fixtures or appliances with
pumping action discharge.

Exception:
Back-to-back water closet connections to double sanitary tees
shall be permitted where the horizontal developed length
between the outlet of the water closet and
the connection to the double sanitary tee pattern is 18 inches
(457 mm) or greater."

Also I'm confused about a double fixture fitting vs double wye fitting- what is the difference and how do I make sure they use the right one?

The plumber came by yest and I think we're all sorted out now

That's much better.

For future reference for anyone who comes by and wants to know about the joists:
For boring holes must be at least 2 in. from the top and bottom edges of a joist.
Maximum hole size is one-third of the joist depth.
For notching the maximum depth of a notch at the end of a joist (where it rests on a wall or beam) can’t exceed one-quarter of the joist depth.
Maximum notch depth in the outer third of a joist is one-sixth of the joist depth.
Limit the length of notches to one-third of the joist depth.
No notching in the middle third of a joist.
Source http://www.familyhandyman.com/floor/how-joists-work/view-all

Since these are toilets, the double wye/eighth bend combination is acceptable.

Don't let them forget about the floor joist repair, and you might want to consider having as much of that galvanized piping as they can get to replaced while everything is opened up.