Kerdi floor drain installation question

[larry528]

Looking at the kerdi shower drain which is required if I use the kerdi system, I have a very basic plumbing question. I have a shower on concrete slab construction.

Never having ripped up a shower drain previoulsy, am I going to find the existing drain on my shower pan glued into the J trap below?

If it is, and I would assume that it would be, how do I get that off so I can install the kerdi drain?

And if I have to destroy the concrete to remove the J trap, how do I get that off? I mean, isnt this PVC plastic welded when installed, so how do you "un-weld" it?

[chuck stevenson]

Larry,

You've been around here long enough to know it is best to keep all of your questions on the same project in one thread. It makes it easier to follow the history.

In many cases the floor is demo'ed.

[ddmoit]

Hi Larry,

I count 3 threads started on what appears to be the same project. The moderators here prefer that all questions regarding a project be contained in a single thread. It's for your benefit. The good folks who offer advice can serve you better if they can easily see the history of your project. A moderator will likely combine all these for you. They can rename the thread to whatever you want to call it.

For someone remodeling a shower on a slab, the normal recommendation is to break out enough concrete to replace the piping at least past the trap. Perhaps your shower isn't that old, and this won't be necessary.

You are correct in thinking that PVC (or ABS) piping cannot be un-welded. Instead it gets cut, and new pieces are welded (chemically) to the old.

[Splinter]

Larry, I think its safe to assume your P-trap below the slab is a solvent welded connection. You're going to have to cut the pipe somewhere. On the plus side, the Kerdi drain extends deeper below the surface than your existing clamp-type drain, so if you can cut off the clamp drain as high as possible, you may still have enough of a stub coming out of the P-trap to glue your Kerdi drain on to...


If you just cant attach the Kerdi drain on to whats left of your plumbing after clamp drain removal, start digging... You can cut out the P-trap and use a coupling to attach the new p-trap to the existing pipe left in the ground.

[larry528]

That will be the deal killer, as far as using a kerdi drain then.

I am not wanting to get into a major slab destruction/P trap removal. I was hoping that it was like a toilet, a O ring or wax ring or something.

Thanks for the info.

Mods, if you can, kill this post.

[ddmoit]

Larry,

You might want to have a quick look at this liberry link before you make your final decision. http://www.johnbridge.com/vbulletin/...ad.php?t=28637

If your pipes are relatively new, and you don't intend to replace your p-trap, it's really not as much work as you may think.

[jadnashua]

Depending on what exactly you have, there are inside pipe cutters that might work. Also, while the pvc connections are solvent welded together, you can peel them apart if you are careful. You'd have to cut from the outside, which may not be possible, though.

The bowl or funnel of the Kerdi drain is larger in diameter than most other drains, as was mentioned. You may not need to crack much concrete, though, depending on what you have.

[Rich Turley]

In reading the your other thead it sounds like a fiberglass pan over cement. Often times these drains are not glued, but just pushed down and sealed with a rubber gasket. It may come right off without cutting, but you will need to add to it for a mud pan. It may work out well with no concrete work required, just hard to say from here.

Rich