Lead Pan and Repair

[FMcCracken]

We recently completed a project where our plumber installed a lead shower pan. Now, the client would like to change the drain to a different type rough which requires penetrating the lead pan. Plumber says he can't warranty the modification because of penetrating the lead pan and he would instead like to replace the whole pan. Replacing the pan is a non-starter because the wall tile is custom, one of a kind and even if it could be redone, there's a 6 month wait for the tile.

I always thought you could repair or modify new lead pans. Old ones - no way, but with new, seaming is relatively easy.

Worst case scenario - a 2' x 2' square gets replaced around the drain rough and the old pan is folded/ seamed to the new patch. It may require hot lead to be poured on new seam folds and their corners.

Any guidance from you guys would be much appreciated.

Frank

 

[Jadnashua]

First, IMHO, the use of lead or copper pans is a throwback to ancient times...there are MUCH better methods. Second, it is highly unlikely (possible, but rare) that the pan is installed on a sloped bed. Almost always, they end up flat on the floor. Technically, that's a plumbing code violation! Code requires the waterproofing layer to be SLOPED. One flat on the floor cannot be. Tile and grout are NOT the waterproofing layer in a shower...they are decorative, wear surface. What happens is that some miniscule amount of water penetrates the tile and/or grout, and, on a flat surface below, accumulates rather than drains to the weep holes (assuming good workmanship and they remain open) in the drain. What you'll find with a liner flat on the floor is that eventually (could be months, maybe years), the grout will stay dark because the base is always wet, and things can start to smell like a swamp.

Putting a patch in the liner would also mean ridges, further restricting the water from seeping out, making the problem even worse. Yes, you can make the liner water tight again, but it's not right, and that's only part of the problem.

 

[Sponsor]

 

[hj]

The ONLY way to properly "repair/modify" a lead pan is to "lead burn" the new piece into the liner. That is a skill most plumbers NEVER acquire.

 

[FMcCracken]

First, IMHO, the use of lead or copper pans is a throwback to ancient times...there are MUCH better methods. Second, it is highly unlikely (possible, but rare) that the pan is installed on a sloped bed. Almost always, they end up flat on the floor. Technically, that's a plumbing code violation! Code requires the waterproofing layer to be SLOPED. One flat on the floor cannot be. Tile and grout are NOT the waterproofing layer in a shower...they are decorative, wear surface. What happens is that some miniscule amount of water penetrates the tile and/or grout, and, on a flat surface below, accumulates rather than drains to the weep holes (assuming good workmanship and they remain open) in the drain. What you'll find with a liner flat on the floor is that eventually (could be months, maybe years), the grout will stay dark because the base is always wet, and things can start to smell like a swamp.

Putting a patch in the liner would also mean ridges, further restricting the water from seeping out, making the problem even worse. Yes, you can make the liner water tight again, but it's not right, and that's only part of the problem.

Yes, agreed, there are better and more modern ways to create a shower pan, but here in NYC, Building Architects specify lead pans be used. We often petition for waivers by providing specifications and test data for approval of more current methods, but in a full renovation we need to pick our battles and in this case, lead pans did not make the cut.

All our pans, whether lead or Laticrete 9235 or Hydro Ban or other material, are on a sloped bed. We have learn by other's and our own installations why a sloped substrate is important, regardless of Code requirements, and why it is crucial to have unobstructed weep holes.

I wasn't sure about the ridges though. I figured they would be part of the patch, but I thought they would be a result of folding over the edges at the patch perimeter rather than from, as HJ recommended, the lead burning of the patch to the existing lead pan. Once that term was used I had a term to Google and learned the method and its result. Very cool, but as stated by you, not a comprehensive solution.

Thank you for your help. I hope I can repay the assistance, if not to you, perhaps to someone else in need.

Frankie

 

[FullySprinklered]

HJ might be the last person on planet earth who has hands-on experience with lead shower pans. I ripped out two of them in an old Victorian sorority house in Athens back in 1992. I assumed that they were probably the last ones in the western hemisphere. As a matter of fact, they're the only ones I've ever seen. Kudos to the architects in NYC, always on the cutting edge.