The shower is on 2nd story of a high rise condo building (below is an office space). The drain is 2" . We don't want to raise the shower floor.
There is beam below and shower is on the left, bldg sewer on the right. If we stay to the left of the beam then the pipe will be too low, as we only have 8" drop to the bldg sewer in 1st flr ceiling. IPC 2012 in Washington DC allows 30" horiz between the drain and the trap. If we use a 2" drain with 1/4" slope can this be done within 30"? Where will vent pipe go. Inside wall before trap? in horizontal section? Can we exceed 30" and will that be allowed by code based on any exceptions?
Will 30" lead to any odor problems? or clogging?


What will be the minimum height of the shower drain if we used metal fittings? PVC fittings?

If we keep the trap below drain and raise the shower floor what will be minimum height of the shower floor if using metal fittings? PVC fittings?

5 feet for 2" trap arm. vent after trap. you can lie a san tee on it's back for the vent or better run the vent off the top of a san tee as the bottom will be the drain and the top the vent and the side the inlet from your shower drain.

OP's referring to a running trap, not a long trap arm.

What kind of shower pan are you going to use(prefab fiberglass/acrylic, site built tile,...)? How far horizontally is the beam from the proposed shower pan drain centerline?