Questions & Answers

I want to re-tile my shower floor (about 60”x 38” on a concrete slab). I’m a competent DIYer, but my plumbing experience is limited to replacing sinks, faucets, and showerheads. I’m intimidated by the drain. The shower has a rusty cast-iron drain (see photo 1) with partially clogged weep holes. What are my options for the drain? Does it need to be removed? To remove it, do I have to remove tile, concrete, etc. all the way to the foundation? Can I somehow adapt it for use with a different drain (a 3-piece drain, or should I convert to a sealed system)?

My overall question: is there a straightforward way to re-do the shower floor tile that a competent DIYer can do?

Background details:

• House in Lodi, CA was semi-custom built in 1985. We bought from the original owner.

• Photo 2 is a small section behind one wall of the shower, next to the door opening. I believe the black material is a hot-mop shower pan, am I right? The wall looks like cement board.

• The curb is not sufficiently waterproofed, so I need to replace it. I’ve removed tiles and concrete/wire to expose 2x4s underneath. The "waterproofing" consisted of tar paper. The paper is damp, but the wood had not swelled enough to crack or displace tiles. It seems like a minor miracle that there isn't rampant mold. Why would anyone make the curb without good waterproofing (rhetorical question)?
  

• One corner of the floor is exactly level with the drain; the rest of the floor slopes to the drain, but nowhere near ¼” per foot.  

• I can hear water dripping into the drain for a while after the shower is used, so that is why I think the weep holes are not totally clogged. Is that a reasonable inference?