I was short on work and someone i knew asked me to do a shower pan for them. The guy had some Denshield he gave me to use for the backer. I had done a shower pan before in my own house, however when i built mine i followed the instructions of a fine homebuilding book i have on tiling and used cement board in it. So when i started this new shower pan job i didnt think to check the specs on the product.
The assembly is as follows. Roofing felt, pre-sloped bed, membrane which runs about 10 inches up the walls, denshield 1 1/2 inch off membrane, and roughly 2 inches of deck mud.
What are my options at this point? I have thought about it for a long time and all i can come up with is to leave it in, or tear out the entire base.
I have read in various other forums posts from people who say the denshield can sit in water for a year completely unaffected. So why do they not approve it to be set into the shower base. This really bothers me because i am always trying to put extra time into reading to make sure this kinda stuff doesnt happen!
Replies
Not clear as to what you've done
You have the felt behind the membrane?
Sounds like felt on the studs with membrane then going 10" up the wall OVER the felt?
That's a no no. Any moisture that penetrates the backer board runs down the felt INTO the pan, sounds as if you have it running benind the pan.
Also if you have your backer board buried in the mud it will wick water whether it's denshield or concrete backer board, again a no no.
But you say it's an inch & half above the membrane, does that mean it starts 12" up the wall or it's 1/2" into the mud?
Joe H
to clarify....
Sorry, the roofing felt is under the first layer of mud... its not up the walls at all... its really irrelevant.
The membrane sits on a pre-sloped layer of mud (first layer). Then the 2nd layer of mud is placed on top of that. There is nothing on the studs around it except for denshield. The 2nd layer of mud is 2 inches thick and the denshield stops 1 1/2 inches off the membrane (so it runs 1/2 inch into the 2 inch layer of mud).
I know that the denshield isnt supposed to be in the mud. However, it is now, so what is the best solution.... do i rip out the whole base? The assembly is pretty much the same as an article in "Tauntons, For Pros By Pros, Tiling". Except instead of concrete board i used the denshield supplied by the homeowner. So im pretty sure the only no, no was running the denshield down into the base.
Maybe i should draw this stupid thing!
Thanks for your time
do i rip out the whole base?
Well no, BUT, you have nothing behind the denseshield to direct water to the pan. You need felt or something behind it un;ess that stuff is absolutely water proof and all the joints are sealed.
Water goes through grout, through backerboard and I assume (bad word that) denshield.
Take you multimaster clone to the densewhield at the mud level (careful you don't damage the liner) and then tear the denshield out and put some felt on the walls so it drains into the pan.
Your bed is ok, but the walls aren't.
Joe H
Pull out the Denshield. I wouldn't advise trying to cut the bottom strip out while in place, you could easily nick the membrane.
So I'd advise pulling the Denshield. Easy to do if the panels aren't already mesh taped, and also easy if screwed in. If nailed, they'll get trashed when pulling the nails. Which could be a good thing, then you can toss it al out in the dumpster. lol. Don't be to concerned with dinging up the mud.
You can then either reset the panels, this time keeping them off the mud, and pack the damaged tiling bed with new mud...or toss the densheld, staple 6-mil poly on the studs, lapping over the CPE membrane low on the walls. Then cement board over the poly. Then mix up new deck mud and pack it in whatever damage there is to the tiling bed.
If you do reset the Denshield, realize that all cut sheet ends, plumbing penetrations, etc, have to be waterproofed. You can't let water touch the core of the sheets.
Good catch on your part, and bravo for you for doing the rght thing. You are a fine man for standing tall and correcting this. Water wicking onto the ends of the Denshield panels could make short work of them.
The felt on the floor is fine, a slip sheet under the preslope.
All my opinion.
shower
Personally I would go the Schluter route. Follow their instructions and be done with. Peace of mind. Not having to worry what would happen if the HO phones you and says: Please repair at your cost and fix the damage it caused