Ask Me Help Desk - Shower Stall bolt down Drains

I'm in the process of redoing my shower and have removed all the material from stud to stud and down to the subfloor. I would like to replace the shower stall drain portion that is under the subfloor without ripping out the entire subfloor to get to it. My question is, is the portion of the drain that is under the floor generally a screw on type or does the top metal plate transition into PVC that is glued to the PVC P-trap under the floor or can I try to unscrew it off without fear of it not being a screw on type and in welded on to the PVC pipe with glue. Looking down the drain, I can't tell if it is screwed on or glued on to the PVC drain pipe under the floor. Thanks for the help

Quote:

Originally Posted by The_chomp

I'm in the process of redoing my shower and have removed all the material from stud to stud and down to the subfloor. I would like to replace the shower stall drain portion that is under the subfloor without ripping out the entire subfloor to get to it. My question is, is the portion of the drain that is under the floor generally a screw on type or does the top metal plate transition into PVC that is glued to the PVC P-trap under the floor or can I try to unscrew it off without fear of it not being a screw on type and in welded on to the PVC pipe with glue. Looking down the drain, I can't tell if it is screwed on or glued on to the PVC drain pipe under the floor. Thanks for the help

Hey Champ!
It sure would have helped if you would have told us what kind of a shower you took out. That way we would know what type of drain you're trying to remove. Would you care to share with us that with us? Tile or manufactured plastic shower enclosure? I'll wait on your reply. Tom

Hello Tom

Sorry for not including all the relevant information. The shower stall was tiled. Walls as well as the shower pan. After removing all the tile and greenboard from the walls and removing the tile off the shower pan I removed the morter bed and tar paper, actually it was layers of roofing shingles that were laid in there then hot tar on top then a mortar bed on top of that, all that was left is the drain sticking up in the middle of the stall about 2 inches high. The shower stall measures 48x32. The drain is cast iron and two halfs bolts together with three bolts. I'm sure you are familiar with that type.
After removing the three bolts that bolt the top half with the bottom half of the drain, all that is left is the bottom half of the drain under the subfloor. Judging from the vent pipe going up the now exposed wall to the roof of the house, I can tell that it is probably PVC plumbing.
I would like to replace both halfs of the shower drain since I have it out this far, but I'm not sure what that bottom half looks like or how it is assembled. I don't want to mess with it if it is a PVC P-trap under there welded (glued with solvent) to that cast iron half under the floor some how. My question is what would be the best way to try to remove the rest of that drain down to the P-trap without creating a big replumbing job? Would it be better to leave it alone and try to match a new top half with that old one under the subfloor and clamp a new water proof membrane between the two halfs and leave it alone before reconstructing a new shower pan?
Hopes this helps explain my situation better...

Thanks for the information. I'm trying to ascertain exactly what type of drain you have. Caulk on or flange type. Does you flange look like any of these?
Could you take a picture of it and sent it to me? Regards, tom

Hello Tom,

The shower drain is exactly the type shown in the second jpg (Cast Iron Shower Drain.jpg) type you sent. I can pry it up off the floor a little bit and it is exactly that type. Shining a light between the floor and the drain under there, I think I can see a threaded PVC adaptor screwed into the bottom of the drain, not sure though. Looking down the drain and scraping the gunk in there, the metal inside is so corroded that I cannot tell for sure that it has threads or not, but now that you sent the picture, I would guess that it once did. I don't want to force anything too much 'cause I don't want to break any thing and create a worse problem. I have tried to unscrew it off with some preasure but it won't give. Have any suggestions on how to get that off short of tearing into the floor or damaging the plumbing? BTW: the shower is on second floor and the plumbing is between floors.

You have a cast Iron Drain that's secured by a lead and oakum poured and caulked joint. You must first unbolt the top piece and remove it. The lead joint will now be exposed. You can remove the lead joint by taking a drill bit that just fits in the opening between the hub and the pipe and drilling a few holes through the lead into the oakum. Now take a screwdriver and start to lever up the lead ring. Once the ring's up where you can grasp it with a pair of pliers you can simply peel it out. Now pick out the oakum and the drain's clear. Good luck, Tom