Here are images of my plumbing system from Revit:
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The biggest challenge was definitely connecting the plumbing fixtures to the branch pipes for the back-to-back bathrooms. Even after trying to use the tool to extend the pipe from the fixture and attach it connect it to the branch pipe manually, I would get an error (for a couple of the fixtures) saying the distance was too short or there was no auto route. Because of this, I am not sure if the lavatories on the right are connected properly. I also had not added walls into the bathrooms to account for where the pipes would be, so I added them for this module.
The bathrooms on the second and third floors were stacked directly on top of each other, so I was able to copy and paste once I had figured out the connections on one level, making the design fairly quick and straightforward once I had figured out the connections.
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Looking at the model coordination, the plumbing system does interfere with the structural system. The pipes connecting the fixtures to the branch pipes intersect the beams below.