Mark's shower project with hot mopped pan and cast iron shower drain

[halfdome]

(I love the people on this forum! I've found answers to countless questions while working on my bathroom! Thank you! Finally, here's one question I failed to find. First post.)

The cast iron shower drain the hot mop guy installed is not level. The pink arrows in the attached photo show water pooling in the two spaces between two weep holes on either side of a bolt. He's coming back in the morning (Friday) to take a look. What's the best course of action at this point?

1. Ignore it. It won't cause any problems for the next 20 years.
2. Get him to demo the whole thing and do it again, correctly.
3. When that fails, is it so bad that I have to now pay someone else to demo it and do it correctly?
4. Some acceptable workaround/hack???

Background: southern california, single family home, 2nd story master bath, plywood subfloor, 43" square corner shower, centered 2" abs drain pipe. The hop mop guy has 20+ years experience pouring pans and was done, start to finish, in under an hour.

My layman's perspective: It needs to be redone correctly but I fear my chances of getting a contractor that's already been paid to agree to demo it and redo it are slim to none. I'm worried he'll fiddle with the bolts to make it level and that'll compromise the waterproof integrity of the pan and I'll be worse off.

Eagerly awaiting your expert advice. Thank you!

[Kman]

Welcome to the forum, Mark.

Do you have access to the plumbing below the floor? If so, can you see the riser going through the floor, and is it plumb?

[halfdome]

Thank you and thanks for the quick reply Kman. No, I'd have to rip open the ceiling in the family room below to access the plumbing. The rest of the bathroom is finished tile.

[halfdome]

Here is what it looked like pre-hot mop. Builder had originally installed a fiberglass shower pan. Did he nudge the drain pipe out of plumb when he poured the preslope?

[halfdome]

No way to tell if it's plumb but here's what it looked like after he poured the preslope.

[jadnashua]

You have me a bit confused...most hot mopped showers I've seen or read about do not have a mortar preslope...they build it out of the tar paper and tar. If you have a mortar preslope, why not go with a conventional liner?

[halfdome]

Hi Jim, I've read on this forum that a mortar preslope is not necessary when hot mopping but it is my understanding that it is a common practice in Southern California for second story plywood subfloors. I can't speak to the pros and cons of either method.

I wasn't clear about this, but the hot mop service included installing the cast iron drain, pouring the mortar preslope, and hot mopping. All in ~45 minutes.

[halfdome]

Despite confirming with the tile setter that he would protect the weep holes in the cast iron shower drain, he didn't. He went with a mortar dry pack. After he left, I unscrewed the capping plate on the drain to find dry mortar sprinkled in through the weep holes. Familiar with the design of this LASCO #5 EZ Test Drain, I knew I could safely shove in a paper clip at the correct angle and see if they were clogged without damaging the hot mopped tar. Surprisingly, dry mortar came pouring out when I stuck the paper clip in 2 of the weep holes. I'm guessing that's a bad thing? I cleared them out pretty easily. The third weep hole was clear for the first 1/3" inch or so, then I hit a brick wall. I was able to get a nail in at the correct angle, break through the mortar and was able to clear it out a little, not much.

Advice on this forum said I should run a flood test to see if the weep holes were plugged. I didn't want the dry mortar to clog the 2 open weep holes so, based on advice on this forum, I shoved some nails up through all 3 weep holes and taped them in place. I temporarily installed a rubber coupler with hose clamps over the 3" drain to extend it up ~5". This allowed me to fill up the pan with water and still be able to look inside the drain to see if the weep holes were weeping. The mortar bed kept absorbing water for about the first hour so I kept adding more. After 3 hours, the 2 open holes started weeping -- a drop every 5~10 seconds. I removed all the nails. It's been over 5 hours now and the 3rd one hasn't weeped. If it doesn't weep by morning, I'll drain the water and get some better tools to try to clear out the clogged hole.

Open to your advice. My question is, if that 3rd hole doesn't open, do I grumble and continue on or stop and rip it all out and start over? Where we're at in the process: drain installed, preslope poured, hot mopped, mortar bed packed, backer board on walls, Redgard'd and ready for tile.

If you suggest continuing on, should I throw a fan on the mortar bed and hold off on tiling the floor until it appears dry? Or do I have to wait a week or more for it to thoroughly dry? It'll be 80 degrees all week here. I figure the mortar bed never gets this soaked during normal shower use and am worried that laying tile and grout too soon will significantly slow down the draining/evaporation of the soaked bed.

Thank you!

[Kman]

Mark, let's keep all questions related to this project on this thread so that questions and answers aren't duplicated, and all the history is in one place. We can give your thread a more generic title if you want, such as "Mark's Shower Remodel".

You didn't mention when the mud bed was done on top of the hot mop, which would help answer your questions. Hopefully it's been a few days. Typically, the flood testing is done after the waterproofing is in, but before the mud goes in. I know that you're really checking the weep holes in this case, but the mud can really soak up a lot of water before it starts through the weep holes.

They do need to be cleared out, though. And if you've prematurely soaked the mud before it can dry enough, you may have gotten more sand or portland into the holes unintentionally. I'd drain it now and let it dry at this point. I don't think waiting any longer is going to produce any better results for that last weep hole.

If it's not draining, you could very carefully chip away the mud at that particular hole and try to clear it. You'll have to be extra careful not to damage the waterproofing layer.

[halfdome]

Thanks again for the quick reply Kevin and for merging the thread. I'll update the thread title. The mud bed was completed Friday afternoon. I waited ~28 hours before I started the flood test. I watched him as he repeatedly squeezed a sponge over the mortar. In all, it wasn't much water. When I saw that dry mortar was still outside those 2 weep holes 28 hours later, I assumed he just hadn't used enough water. I was hesitant to do the flood test but the advice I received outside this forum reassured me that water would just further reinforce the bed and wouldn't cause any damage. I just drained the pan. It was flooded for ~8 hrs. The 2 holes were still weeping fine and the 1 was still clogged. I'm running a fan now and placed the nails back in the weep holes overnight so they don't seal up by morning in case mortar made it's way in. I'll chip away at the mud in the morning.

[Kman]

You'll have to tell us what you want the thread name to be and a moderator will change it for you.

I can't say that I've heard of anyone flooding a mud bed that soon, so I can't say for sure that it's a problem, I just know I would have waited a little longer. For instance, the normal wait time to apply a liquid waterproofing membrane is three days, to allow for adequate drying. Maybe yours will be okay.

[halfdome]

Mods, please rename thread to:
Mark's shower project with hot mopped pan and cast iron shower drain

Faced with a drain that's not level and has a clogged weep hole, maybe damage to the mud bed will finally convince me a do-over is in order. I suspect symptoms of a damaged mud bed might surface in a day or 10 years from now... troubling.

[rebeljeep]

I'm in the beginning stage of building my first concrete shower pan. I've done lots of study about waterproofing the pan. I don't understand why there isn't enameled cast iron pans at reasonable prices. It's like 750-1400$ for a pan made out of about 1/8 of the material of a bathtub that sells for 200$. Hot mopping looks like a great option, but not if it cost a boatload of $$$. And it seems like every shower pan is a boatload of money, except for the Concrete and rubber liner. Ive set my drain, but I wish I would have waited because I actually found some used cultured marble pans on Craigslist.

[halfdome]

Short of running another (potentially damaging) flood test, how will I know if I've successfully unclogged the weep hole? Odd thing is that before the flood test, I had already chiseled out enough mortar to get the nail ~1.5" into the weep hole yet it didn't weep. Advice appreciated.

Tim, it's about $275 in Orange County, CA to install a drain (not included), dry pack preslope, and hot mop a 43" square shower (no bench), assuming you've pre-prep'd the wood blocking.

[halfdome]

An update for the benefit of anyone that lands here from a search engine:

Non-level shower drain: I called a couple local hot mop shops about redoing everything from scratch and instead of soliciting my business, they told me non-level drains are quite common and, as long it's not completely out of whack, it shouldn't cause any problems for an experienced tile setter. As I filled the pan up with water to run the flood test, I could clearly see the asymmetrical pitch the tile setter poured to accommodate for the tilt. Since the hot moppers aren't licensed plumbers, they either refuse to install the drain or they won't warranty the installation if they do. They frequently show up to hot mop a pan and find a drain that isn't level. When my hot mop guy came back to inspect the drain, he insisted it would be fine but offered to unbolt the top half of the drain, shim it with felt paper, and reseal it with tar. Worried that would do more harm than good, I decided to leave it alone.

1 clogged weep hole: chiseling it out from inside the drain with a right-angle pick/awl and nail was most effective. It cleared the immediate vicinity of the weep hole though it still didn't weep. There doesn't seem to be any other viable alternative aside from ripping out the bed and starting over. Drilling through the mud bed to get to the weep hole and repacking it is not an option as wet mortar can't bond to dry mortar. I talked to my tile setter about it and the non-ideal compromise we made was to leave it as-is and he would personally demo the shower and rebuild it from scratch at his own cost if I had drainage problems. He's worked for me and my extended family for well over a decade and I trust his guarantee. FWIW, he says he's willing to take on the guarantee because he trusts the pitch of the mud bed and the tile he'll be setting will properly send nearly all the water down the drain instead of pooling on the surface and soaking through the grout into the mud bed.