Replies

1. 
   Geoffrey | Sep 05, 2007 07:53am | #1

   JNF,

    What type backer did you use? Cement backer boards require a moisture barrier behind them. That barrier should extend down into the shower pan area so any wicking would not be a problem. But...did they install the moisture barrier(i.e. 6-mil poly)?  That's the question!!

   If they did install the VB properly, then the 1/2" clearance is fine. 

                                                                             Geoff

                                                

1. 
   jn_freedman | Sep 05, 2007 04:08pm | #2

   6 mil behind all the backerbaord. Hopefully, this will cut the mustard!Thanks,
   JNF

2. 
   Mongo | Sep 05, 2007 04:10pm | #3

   What kind of "backerboard" did they install in your shower area?

   Mongo

1. 
   jn_freedman | Sep 05, 2007 04:52pm | #4

   1/2" Durock...JNF

1. 
   Mongo | Sep 05, 2007 06:01pm | #5

   Beautiful. I was afraid you'd say "greenboard."

2. 
   Mongo | Sep 05, 2007 06:07pm | #6

   Which now brings me to Question #2:The "PVC pan"...is that a rigid preformed PVC pan, meaning it's the finish material that your bare feet will stand on when showering?Or when you say "PVC pan" are you referring to the flexible 40-mil PVC membrane that was laid over your drypack preslope?Mongo

1. 
   jn_freedman | Sep 05, 2007 06:45pm | #7

   40 mil over a drypack pre-slope.

1. 
   Mongo | Sep 05, 2007 08:38pm | #8

   Then I'd want the cement board higher than what you now have. When they put the next layer of mud on top of the membrane, it'll bury the bottom of the board in the mud. As you've mentioned, water getting below the tile and on top of the membrane could then wick up the cement board.I don't mind the bottom of the board being buried in the mud when doing a Kerdi shower, as water will never get past the Kerdi.But with a 2-part clamping drain and a 40-mil membrane, I'd prefer the cement backer board be isolated from the tiling mud.It's a personal choice of sorts. Some don't mind the backer board being buried, some do.In a perfect worked it wouldn't matter, as the pan mud should never saturate due to properly draining secondary weep holes. But based upon the emails and phone calls I get? The world of shower pan construction is far from perfect.Talk to the installer, see what his plans are.Mongo