Building a bathroom from scratch

[Brian in San Diego]

Yes, Kurt, it has snowed up here already. It snowed on the 8th of October. I’d estimate it was in the 3-4” range. The temperature has been colder than I’ve been exposed to a very long time (mid teens).

Today is Thanksgiving in Canada. Not sure if we’re going to work today or not. I was invited over to friends’ house Thanksgiving dinner last night. It was just like a Thanksgiving dinner in the States with addition of Yorkshire pudding.

[Brian in San Diego]

The drain for the shower was plumbed up through a 10” “hole” left in the basement floor. The 4” slab was poured over about the same depth of styrofoam insulation. I had to cut away the insulation to fit a trap into the space provided. After fitting the trap my friend squirted some expanding foam to replace the foam I had to cut away. It expanded a bit more than expected. My plan is to cut the over expanded foam down even with the existing styrofoam and the fill the hole with sand topping mix to the height of the finished floor.

Once that has set I was going to build the pan out of deck mud. Because of the fact the drain line was centered in the 10” hole, I had to offset the trap. To get the Kerdi drain to fit properly I’ll end up with 2” of deck mud beneath the drain. In watching the various Schlüter videos it appears I should mix up a looser deck mud to go under the drain. Should it still be 5:1 or should it be a little richer? And is it acceptable to use regular sand topping mix (3:1) to fill the hole as I described?

[cx]

You could use the Sand Topping mix in that application, Brian, but I generally just put some of my deck mud mix in a gallon bucket, richen it up with a big handful of whatever thinset mortar I have on hand, or a handful of Portland cement, add a little more water and mix. I find it quite easy to pack under the drain's tiling flange using my fingers and the side of a wood float.

With the grat big ol' gap you say you'll have, you can probably shovel it under there.

My opinion; worth price charged.

[Brian in San Diego]

Well, I got the mud bed in yesterday. And as usual, I’m not thrilled with the results. What I pictured would be the result and what I saw today are photographs that aren’t similar.

So, the question now is, what to do about it. My first thought is to do a little “touch up” work with a brick to knock down the high spots and then fill in any small depressions with thinset. I did notice that the Homers up here have a CBP product called “Speedset”. Says it’s for making shower floors. Wondering if that might be a better choice than thinset. Downside is I’ll probably need a pound or two, not 50.

[cx]

The only SpeedSet I can find at Custom is a rapid setting modified (A118.4 and .11) thinset mortar, Brian.

Technically, thinset mortar is not to be used in your application, but it's done alla time. Doesn't make it right, just makes it popular.

But since you're doing a Kerdi shower and covering your mud floor with the membrane, rather than using it as a final mud bed to set your tiles on, whatever you do to make a solid, flat, properly sloped floor will likely work just fine.

My opinion; worth price charged.

[Brian in San Diego]

Sorry CX, I went back to Home Depot and saw that the product is SpeedSlope, not Speedset. https://www.custombuildingproducts.c...x?q=Speedslope

I assumed I would have to do something similar to what you have stated. My first mud bed was a total disaster and it took me a lot of effort and mess to fix it. This one is a minor fix in comparison.

[Brian in San Diego]

Okay, I’ve sorted out the problems with the mud bed and I’m ready to start laying Kerdi on the floor. Since JB wrote The Kerdi Shower Book I believe Schluter has come out with an array of items that make Kerdi installation in the corners a whole lot easier. I refer specifically to the inside and outside corners.

It appears to me that one could cut Kerdi band about 5” short of each corner on the shower floor, install an inside Schluter Kerdi corner and all would be good. You’d have the 2” overlap with both the band and the pre-formed corners. Is my thinking correct? Or does the Kerdi band have to go under the corners by 2”?

I dare say it appears to be a whole lot easier than when I did my first shower (all those years ago).

[Tool Guy - Kg]

So, the walls and floor would be covered with Kerdi...with a sliver of a gap between the floor and wall Kerdi...

Then you’d drop an inside corner in place and essentially butt the start of the KerdiBAND adjacent to the inside corner?

Or would the KerdiBAND overlap any part of the inside corner?

[Brian in San Diego]

Kurt, your description is correct. Initially I was thinking about butting the Kerdi band to the manufactured inside corner. Giving more thought I think it’d be prudent to overlap the inside corner the 2” over the Kerdi band.

[Tool Guy - Kg]

Yep, extend the KerdiBAND.

Isn’t it cool that even though it’s been awhile since the last shower, it’s easier this time around?

[Brian in San Diego]

Only a slight housekeeping duty of dusting out the cobwebs was necessary as I’ve plodded along on this project.

I chose to blend “old school” with new school on the Kerdi installation on the floor. I cut the first piece 5” longer than the floor dimension. I then cut out the corners so the sides would fold up. Installed that way and then put a pre-made corner in and voila. Done without using Kerdi band. I bought Kerdi band for this project and I’m not sure I’m going to use any of it.

[cx]

Perfectly acceptable method, Brian.

[Brian in San Diego]

Looking forward to toilet flange addition. This bathroom was plumbed with a 4” pipe coming up through the slab. I’m seeking advice regarding the type of closet flange to use as well as what steps will be necessary to get the flange at the same height as the tile. My thoughts are that I’m going to have to do a little demo work on the concrete around the pipe so I can get the flange down to floor level.

[cx]

For that 4" riser pipe you can get an inside the pipe flange, Brian, and that's what I'd recommend. I think they're available with a cast iron flange and the fitting is not cemented, just a press fit with O'rings or other rubber gasket. You can also get PVC or ABS flanges, but I'd get the iron flange if possible.

You'll need to drill through your new tile and into the concrete to fasten the flange with some TapCons or similar screws.

Shouldn't require any concrete work at all other than just flattening for your tile installation.

My opinion; worth price charged.

[speed51133]

is that pipe ABS or cast iron?