So this is the issue, the FU counting feature in Revit ROCKS and it's a huge time saver. It would be even greater if I could connect stack fixtures in a stacked connection. I consulted with our plumbing engineers (we are a MEP Firm) and we do connect stacks vertically. Attached is a Revit model with one of our stack families where you can see the fixture units adding up nicely and the vent units doing so too, as long as the stack fixtures are not connected as a stack. Once I conect the sanitary pipe directly down it just carries the FU of the last element, it would be great if these would add up too. Time saver and avoid human error.
Thank you for your time
Sandra Wohlgemuth
BIM Manager @ MKK Engineering
Plumbing FU_R18 - ADESK (1).rvt