I have a 1 1/2 inch PVC shower drain set in concrete and trimmed level with the concrete surface. I cannot seem to find a solution to an adequate drain installation due to the smaller 1 1/2 inch pipe. Can anyone help? I intend to install a 1/4 inch tile floor base but only after I have located a solution. Thanks

Is the 1 1/2 pipe a PVC pipe or something else?
A shower will drain through a 1 1/2 inch drain so one posibility is to chip the concrete down to a point where you can fit the shower down over the pipe and the shower will be setting solid on the concrete. Now in the 2 inch shower drain insert a 2 x 1 1/2 inch bushing.

You may have to lower the height of the 1 1/2 inch pipe to make it work. If just do some more concrete breaking.

Letmetellu is heading you in the right direction.. for sure!

I would chip out some of the floor so that you get far enough down to install a 2"x1.5" reducing COUPLING... then just need to extend the 2" pipe above the floor to the correct height. This will allow a better seal to be made at the shower strainer when compared to the bushing mentioned.

To reduce the depth/width of chip out needed in the floor, plan on cutting the pipe using an INSIDE PIPE CUTTER with a regular drill (sold at all home supply stores or at a local plumbing supply house)... see picture below. Just open concrete floor about 6-8 inches wide to start, dig out a bit and then cut so pipe is deep enough to install the coupling COMPLETELY below the floor by an inch or so. That should be enough. Then you can dry fit your shower to take measure for final piece of pipe out of coupling and into the strainer.

I would also check the manufacturers recommendations for setting the shower base/unit. We install almost all of our shower units in a base of STRUCTOLITE perlited gypsum plaster. Stuff dries to like concrete overnight and makes for a super solid shower floor. This guarantees that the strainer/drain connection will not flex/break seal over time.

Let us know what you think...

MARK