Bathtub drain

[Fixit man]

Can a 1 1/2" p-trap be used under a 90 gallon tub and then attach to a 2" drain line? The reason is to minimize the size of hole required to move the drain pipe between two floor joist. The previous tub had change a 2" p-trap.

I am also wondering if the vent for this line is ok at 5'6" because everything I read says 5'.

[jadnashua]

You can go from smaller to larger, just not the other way.

[geniescience]

Can a 1 1/2" p-trap be used ... then attach to a 2" drain line? Yes. Like Jim said.

david