Kerdi vs Redgard for tiled shower

[Dan Friedrichs]

I'm planning to do a couple of tiled, walk-in showers in the next year. I've been reading the John Bridge forum (etc), but am curious if anyone here has done a tiled shower and been especially happy with the process.

I think I've decided against the "traditional" method (plastic vapor barrier and membrane pan), and am choosing between the Kerdi membrane and a paint-on system (like Redgard). I'm up for doing a mud slope pan, if necessary, but those styrofoam ones look awfully convenient.

Kerdi can be done over drywall, which is nice. Redgard requires cementboard, but seems like it might be less expensive and easier to apply.

Anyone have an opinion? :)

[Ken Fitzgerald]

I did one in the traditional method of a sloped mud pan and a membrane. It worked well and I have been satisfied with the results. One bit of advice if you decide to use this method. I installed a wire mesh in the first layer of mud. Be sure to NOT add too much water in the mud. I did and when I worked the mesh into the mud, for a while I watched the mesh "pop" up through it. After I applied the barrier, the 2nd layer of mud was much thicker and MUCH easier to get the proper slope as a result.

[Stephen Smith Sr]

I used Kerdi a few years ago and it came out real well. I also used their shower base which was very convenient. It's a bit pricey, but I think you'll be happy with it. Good luck!

[Mike Berrevoets]

I used the full Kerdi kit with the foam base and curb in our master shower a few years ago. And I used it the next year when I redid the kids bathroom but that was just above the tub.

It was pretty easy to use but is extra work. I really like the way the drain integrates with the system as that seems to be a potential leak point on any shower. I do recall that I mixed a lot of batches of thinset. Mix a batch to put up the main membrane on the walls. Then mix a batch to set the foam floor and curb. Then mix a batch to put the membrane on the floor. Then mix a batch to put on the Kerdi strips in the corners. I'm sure the pros have a better method and can probably get it down to only a few batches of thinset but I was kind of "easing" my way into it.

Despite the extra work if I was doing another shower I'd use the same system. Most of the chatter online about it seems to agree that it is a great system it is just expensive. I figure i can pay a little more for materials since I save on the labor.

[Rick Moyer]

Mike, Kerdi foamboard doesn't require thinset to be applied to the wall. I assume you applied the fabric membrane though. We had stripped our bathroom down to the studs since we took out the tub to put in a walk-in shower, and just put the Kerdi board right to the studs and zip sheeting. I'm a homeowner and we hired a contactor with the agreement that I would help. I was really impressed with the Kerdi system, albeit not inexpensive. Same as above, foam base and curb. Tiled over everything. It came out really nice, Very pleased.

[Lee Schierer]

My son did the red guard and it was pretty easy to miss small spots as the concrete board had divots that did not cover well and the tools get goopy as the residue starts to dry out.

[roger wiegand]

I've done the Kerdi membrane and 20 years on it is working well. I've also done mud jobs. Mixing, packing and leveling the dry mortar for one bathroom floor was one of the harder day's work I've ever done. Kerdi all the way for me! I could never bring myself to trust a paint-on product.

Compared to the cost and irritation of a leak the cost of the materials is trivial. I hate re-do's.

[Chris Padilla]

I just finished up my second Kerdi bathroom. The first was a full shower (have posted pics in the past on some thread in here....) complete with the foam ramp, foam bench, foam curb, and really spendy linear Kerdi-line drain/cover. I also used Ditra-Heat on the floor. I can't post links to that forum (John Bridge) but I have a whole thread of my bathroom build. Search on: Chris' Orange Tile Project.

Kerdi is more or less like hanging wallpaper. IF the underlying stud framing is sound, square, flat, and plumb, tiling will be smooth and clean. So take care to put some effort into getting the studs in shape. However, an experienced tiler can get things flat even with a bumpy wall floating thinset and although that isn't really advisable, it is done all the time. Someone skilled in floating mud won't care how your wall is...he makes his own flat, coplanar, plumb, square walls himself.

The second bathroom was a 5x10 hall bathroom with alcove tub. Only the walls above the tub had Kerdi installed and I also used Ditra Heat on the floors.

Both bathrooms took a lot of prep/work on the studs to get 'em in shape but popping up plain, white sheetrock as the backer couldn't be simpler and cheaper, I think.

[Dan Friedrichs]

Thanks, Chris - I recall seeing some pics of your (very impressive) shower, years ago. I'll check out your thread on John Bridge.