Leveling a shower floor - where to start?

After 2 years I've finally decided to try to tackle this problem, our shower floor is uneven and doesn't drain at all. Whoever built it obviously didn't use a level and there are several high and low spots.

I'm not sure where to start, I was thinking I could try to pry up the tiles and reuse them?

If I do that, what do I do next? It's really tough to figure out what the builder did here, seems like there are way too many layers under those tiles. Should I just carefully pull up everything and go from there?

OR...should I look into getting a plastic tub that will just go on top of everthing that's there and just get a drain extender? I don't need something that looks amazing, just something that drains like it should.

 

That's a suspect looking drain. If it were me, I'd rip it all out to the subfloor, lay a mortar preslope, pvc liner, final slope, thinset then tile. Using one of those clamping drains designed for the rubber liners.

Google John bridge forums, great resource for tiling.
Those guys are professionals to the T and will know the best solution for you. The last thing you need, is to do a quick fix, and have the shower leak causing disaster.

 

no such thing as removing tile carefully...

I would think laying tile over the current floor would be easier, don't make it level though maybe it all slant slightly towards the drain...

plastic tubs / stalls suck... tile is much nicer, don't give up just yet!!

check out a few diy youtube videos

 

That's another thing I was thinking of, just keeping everything in there and putting a new layer of properly sloped tile over it all and adding a drain extender. From what I've looked at so far it doesn't seem like whoever did the work actually knew what they were doing.