Is this the best fitting? Replacing cast iron stack

[JG plumbing]

When I look at the pictures of this fitting to me there is an obvious difference between the T and the double Inlet t. If the radius is equivalent then it should be fine but it doesn't look like it is. The manufacturers try to get away with changing as little as possible to their dies and manufacting process. The article highlighted above is saying if the manufacturer can make a fitting that does x them it'll be legal in that position.

It looks nothing like the sanitary tee radius.

You can't shoot poop into other fixture lines. Branch lines aren't designed to clean obstructions that are sitting in the pipe. They are designed to carry solids that are floating.

 

[JG plumbing]

I looked at the manufacturers site and they conveniently don't give you the correct radius measurement. Most people can't do and don't know the math involved to figure it, so they get used. They are not legal for drainage in Cedar Rapids unless you can get a letter from the manufacturer showing the drainage radiant. Although I think they may have gotten a new inspector now. The old one would not let you use and double tees without that letter.

They are used in attics.

 

[Twowaxhack]

Wisconsin’s were used and still are used in many areas in single stack bathrooms.

The 2” side inlet is above the centerline of the 3” to maintain the vent for a bathtub or shower attached to the 2” side inlet.

Above this in the stack is a 3x1.5” tee for. the lavatory.

In the OP’s case he’s using the side inlet for more than a bathtub or shower. That’s the only problem I see code wise for its use.

Big deal......it works fine. Codes vary, exceptions are made. Plumbing code is theory........