Replies

1. 
   Guest_ | Feb 18, 2000 08:21am | #1

   *
   Speaking as a homeowner, I had bad luck with "hot mopping" even though it was something of a standard for many years. About 7 years after my home was built, my shower stall developed small weeping leaks where the hot mop had failed. Thank goodnes it was to through the outside dam, where I could see it. I've ripped the stall out, and I'm planning to have it rebuilt with CPE membrane. Just seems to me the flexible CPE will go a long way to preventing future failure. Also check out Michael Byrne's book "Setting Tile" - he highly recomends CPE.

   Most of the "premium" shower stalls I see done in So Calif, are done with mortar floated on walls, over wire & 15 lb felt, or "J-lath" (?). I've been told it's more forgiving of framing settling, & avoiding cracking tiles. I've been thru several moderate earthquakes, it still looked fine, for what that's worth. It may be a regional preference in So Calif. It certainly takes more skill to apply than screwing in cement boards.

1. 
   Guest_ | Feb 18, 2000 10:10am | #2

   *I choose CPE. Although some will disagree--that is, I have met some who disagree with this--hot mops will fail. I believe they fail because the material fatigues at the ninety degree intersection between the wall and floor. I don't think the intended use of the material is for such an angle. That this joint is subject to repeated cycles of movement of the substructure only exacerbates the problem. My experience is that hotmops develop cracks at the wall/floor joint. Also, there is installation error. Just how longlasting a hotmopped shower receptor is is consequent to how the material is bonded to the drain flange. Typically, the hotmop guy will simply lap the material up to the flange and rely on the tar to provide a seal. Sometimes, they may use a caulk. I question how this will last because 1)the tar will pull away from the flange when it cools, 2)the caulk will not permanently bond to the tar, 3)the tar, after it cools, becomes brittle and is subject to cracking. Having said all that, I would consider hotmops for, say, exterior waterproofing of decks and walks.Trowl applied liquid membranes are expensive and prone to installer's error. I have used these materials successfully many times and would use them again when they are spec'd--sometimes by me--or the job conditions dictate their use. I primarily use this for specialty jobs.Copper or lead pans are good but require special skills and tools. I think these are somewhat passe with the advent of newer materials.

1. 
   Guest_ | Feb 18, 2000 10:30am | #3

   *Rich,Very good summation.Having applied hot-mop, lead, copper, UVA(Ultraset), Tile-Tite, Laticrete's fiberglass w/ mop, Chloroloy(CPE) and others such as Semco .........I vote for the CPE and a well trained qualified tile man who uses tar-paper, expanded metal lath, scratch coat (more than one if necessary) and a good brown coat with the tile applied while the brown is still plastic.Takes a real tile mechanic to produce a real tile job that will survive the unforgiveness of water and the throes of a hurricane.Best place in an earthquake, hurricane or tornado is in the shower built by a good tile man.You can take that to the bank!!!!

1. 
   Guest_ | Feb 18, 2000 05:23pm | #4

   *Not familiar with the acronym CPE. What is it? Are any of these shower pans mentioned above composite, fiberglass, or plastic?Matt

1. 
   Guest_ | Feb 18, 2000 07:18pm | #5

   *Im with Rich and jj. I vote for CPE (Chlorinated Polyethylene) membranes. I also use Ultra Set trowel on membranes, but as Rich pointed out they are expensive. The only time I use them is if I have a shower stall with weird angles or benches, etc.For any tile job be it floors or walls, mortar beds are the top option. For walls, my second would be cement board installed over 30# felt paper. Although Ive heard alot of good things about Hardibacker, but have never used it.

2. 
   Guest_ | Feb 19, 2000 06:14am | #6

   *Jeff, what you say about the longevity about a properly executed tile installation reminds me of some pictures I had seen in a trade magazine. It was shortly after the Northridge earthquake in Southern CA and the pictures showed a shopping mall that was utterly destroyed. Amidst the piles of rubble was this one wall still standing. It was impressive because everything else had been leveled. The wall was about ninety feet tall and over 100 feet long. The wall was entirely cladded with a porcelian tile. Not so much as a crack or missing tile. Later, it was found that the masonry behind the tile had turned to powder, pulverized by the whole lotta' shakin'.

2. 
   Woodbros | Feb 19, 2000 08:32am | #7

   *
   We've had excellent with CPE and poured concrete bottoms
   with denshield tilebackerfor the walls etc.

1. 
   sionoloco | Feb 20, 2000 04:48am | #8

   *I'm not sure which parts of the above suggestions might apply to a small bath/shower in a prewar NYC apartment where the greatest danger comes from the lawyers who live above and bellow. The expression "vapour barrier" is strongly emphasized in the 40 page alteration agreement! There's nothing left of the terricotta walls that originally made up this 4'X 4'X 10'h bath/shower and I've got it framed up with 3-5/8" metal stud, which contain a lot of plumbing, AC equiptment (above), lighting, speaker, w/d vent running through, electrical panel(s) in the entry wall (facing out) etc. Need I say, we have to do things here in very tight situations. We commonly use metal studs with Wonderboard or Durock and a lead pan, mud and tile. I don't really like the system. Can I wire lath metal stud and do a "proper" mud job from there? Are the technologies mentioned, waterproofing membranes that could apply in t

3. 
   Bobby_MacFee | Feb 20, 2000 04:48am | #9

   *
   What is the consesus on shower pans:

   1. CPE

   2. Hot Mop

   3. Trowel On

   4. Other, copper etc.

   And while I'm at it, how about the walls? Just wonderboard over tar paper, or something more elaborate like tar paper under a floated job?

   TIA