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Pre-slope and liner install bad??

Posted by itltrot (My Page) on
Sun, Jul 27, 14 at 17:12

I'm back again. I swear I'm about to walk away from this whole house.

DH and I have flip flopped on the install of the shower pan and after talking to 3 local contractors we finally decided we were going to do it to make sure it was done right.

One of the original posts here

After talking to a new acquaintance, DH learned the guy was a plumber by trade back in California and just moved to Oklahoma. They started talking and he said no problem. He knew preslopes, liners, slope the whole thing.

He showed up Friday evening to help us. He packed the preslope the mud looked good. Held it's shape but didn't leave residue on your hand. DH caught a couple areas where the slope didn't look right and no problem he agreed and reworked it as he was going.

I had more reservations. He was unsure about our concrete curb on our concrete slab and how the liner would attach. Thought we might need it hop mopped which no one around here does. He called a buddy who lined him out. The liner was to be attached to the concrete curb with mortar and the lath put over the top of it.

The whole time I'm looking at the preslope it looks flat to me. DH kept saying there is slope. After the guy leaves DH and I are discussing it and he says he noticed a "speed bump" around the drain on one side which he is certain will prevent water from draining. Again I say the whole thing looks to flat.


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Next day the guy comes back and feels comfortable with going forward and lays the liner. All we could find to seal the drain was one of the expandable drain plugs with the wing nut. He used silicone to seal the underneath the liner to the drain. He did dam corner and the liner is plenty tall enough. He said let it dry overnight then fill with water for 24 hours.

DH and I didn't go ahead and waste the water to fill it because I didn't like a wrinkle and how it still appeared flat. DH was still concerned about the "speed bump". He filled a pitcher full of water and poured it around the shower. And there is tons of water pooling. By the wrinkle and by the speed bump.

I also noticed the weep holes seem clogged with silicone and the liner wasn't cut for them.

Standing water

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Clogged weep holes

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DH is wondering if we can pull back the liner and add on to the preslope to fix the flat spots and birdbaths? Maybe use a bonding agent to get the additional material to adhere to the original? And if necessary replace the liner? Or is this a total do-over back to the slab?

I am hoping it's not back to square one because that ruins the noble crack mat that is under the preslope and curb. Which would mean at least $200 down the drain. But I guess I'd rather throw the money away now instead of the whole pan failing.

Where do we go from here? We supplied all the materials and have yet to pay him anything because he didn't want paid until the job was complete. DH plans to talk to him tomorrow but I was hoping for plan of attack before DH calls.

Follow-Up Postings:

RE: Pre-slope and liner install bad??

"We supplied all the materials and have yet to pay him anything because he didn't want paid until the job was complete."

This was the best thing I read in this post.

RE: Pre-slope and liner install bad??


Installing the membrane, then putting a bead of sealant on top of the membrane, then bedding the top drain piece into the sealant and bolting the top piece down? This is wrong. The sealant should be applied underneath the membrane, then the top piece gets set "dry" on top of the membrane and gets bolted down.

Sealing between the membrane and the top piece of the drain seals the weep holes. That's wrong.

As to the slope, or lack thereof? The preslope itself will sit in compression underneath the membrane. Nothing gets bonded to the preslope. So "slope repairs" can sometimes be made to the preslope to shave high spots and fill low spots.

To fill low spots, you can make a portland slurry. Water plus powdered portland cement. Brush that in the low spots, then you can pack new deck mud (typically 5:1 sand:portland) over it, shape it, and reset the slope.

If the entire bed is questionable, it sometimes is easier to rip it all out out and start from scratch than it is to try to spot repair here and there.

Deck mud should be fairly lean with regards to the content of portland cement in the mix. So if you felt better removing the existing bed and starting over, you should be able to do so without damaging your Nobel membrane.

If you do rip it all out, you can reuse your membrane. Just take care unbolting the top drain and removing the sealant from between the drain and the top part of the drain.

Firs thing to do? Unclamp the drain right now and clean up the sealant. Even if you were to accept the preslope "as is" and move the project forward, you want that sealant gone. You'd then properly seal the underside of the membrane to the bottom part of the clamping drain, then re-bolt the top part of the drain down with no sealant between it and the membrane.

Hope that makes sense.

RE: Pre-slope and liner install bad??

Tre, thanks. I thought it was awesome he didn't ask for money yet and even turned DH down when he mentioned it.

mongo, He actually did install the silicone under the membrane to the lower part of the drain. There was just so much of it, it oozed out everywhere.

I think it all makes sense. The slurry kinda acts like a bonding agent? I'll show this to DH and we'll decide how to proceeds. It would speed up the process to just repair what's there but I don't want to kick myself if it fails in a couple years.

One thing the installer thinks we should do (but I'm certain I've read on here it's a no-no) is after the preslope, liner and slope is finished add redgard to the top of it. I think that would be sandwiching in any moisture granted nothing should get past the redgard to beguin with. But I thought I'd ask.

I'll check back after we've decided how to proceed and how the installer deals with it.


This post was edited by itltrot on Mon, Jul 28, 14 at 15:17

RE: Pre-slope and liner install bad??

It's really not advisable to add a vapor-impermeable membrane over a vapor-impermeable membrane with deck mud in between without modifying the drain to a divot.

You choose one path or you choose another. When you go from one path to another and back again, you can get lost.

RE: Pre-slope and liner install bad??

Can you say "Moisture Sandwich?"

RE: Pre-slope and liner install bad??

I think when we eventually build our forever home, we'll just bathe outside in the rain barrel. Seems easier than finding someone local who can put in a shower correctly!

RE: Pre-slope and liner install bad??

I'm going to say no to moisture sandwiches!

DH and the installer talked a little yesterday and he seemed shocked that there were birdbaths but gave no indication that he wouldn't fix it.

He was unable to come over last night due to getting called out for his full time job. He is planning on coming tonight. I'll keep updating.

RE: Pre-slope and liner install bad??

After a week of the installer being busy when we were available and us being busy when he was available we finally got the preslope fixed and liner installed. Flood testing currently 20 hrs in and holding water!

Now I'm stuck once again. I can not find lath for the curb in town. Lowes points me to chicken wire in the gardening section. DH had to go to OKC recently and stopped at HD and bought this METAL LATH/202093395

But installer says its wrong stuff. What exactly am I looking for? Can anyone link me to the right stuff via HD or Lowes website?!

RE: Pre-slope and liner install bad??

"Chicken wire" can be used....but expanded diamond lathe is preferable. It oughta be available at Homers' or at Lowes'. Check in the concrete section....

RE: Pre-slope and liner install bad??

The lathe your husband bought was the correct material.

Remember, no nails in the top or on the inside face of the curb. Only on the outside.

Watch Harry.

RE: Pre-slope and liner install bad??

I thought it had to be right because I couldn't find anything else that matched the descriptions I had read online.

I have Harry's tutorial printed out and refer to it regularly while the work is being done.

No worries, can't nail in the curb anyways since it's concrete!

RE: Pre-slope and liner install bad??

"No worries, can't nail in the curb anyways since it's concrete!"

Not so fast sunshine! lol

You'd be amazed at the lengths people have gone to in order to screw up a shower. I've seen people drill and drive tapcons through the membrane and into a concrete curb.

RE: Pre-slope and liner install bad??

You are right. I've had to remind DH a couple times when installing backer board not to screw it in low.

Thanks again for all the help. Hopefully the curb will get finished this weekend!

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