Master Bathroom — Part 6

 Yes, here it is, finally!  (although yes, it’s a small post, but I wanted to get it off the table, as it were, because it might be some time before there’s more to show) 

When last we left the subject, the master bathroom shower had been lined with cement backerboard, and was waiting for the Kerdi waterproof membrane to go on.

The corners are the most vulnerable places where water can infiltrate into the wall (where planes intersect: two planes or three).  Where two planes intersect (two walls, or wall and floor, etc.), a band of waterproof membrane is applied, using a thin layer of mortar.  Then a sheet of the membrane goes on the wall (or floor), overlapping the corner bands.  In the three-plane corner, there is a pre-formed piece that is mortared in, overlapped by the bands and then the sheets.

So, after the walls were covered, the drain depression in the molded plastic foam shower pan was filled with mortar, then the black plastic ABS drain part was cemented to the underlying 2” ABS drain pipe, while pressing it into the mortar bed—a critical operation.  All good, fortunately.

The 2” hex mosaic floor tile then went down, using thin-set mortar.  The tile came in square-foot sheets, held together with a thin mesh.  There was yet another, smaller drain fitting that had to be installed at the same time.  A little tricky, and the small tiles had to be individually cut to fit properly around the 4” square stainless steel drain cover.

After letting the mortar cure for three days, I grouted the tile with a light platinum gray unsanded grout.  Ordinarily I would have preferred sanded grout for 1/8” spacing between tiles, but the gap between some of the tiles ended up being a little less.  Sanded grout is recommended for gaps 1/8” and larger; unsanded grout is used for 1/8” and smaller gaps.  I tend to leave 1/8” gaps, where either type should work.  (The sand makes the grout stronger; the unsanded is more easily pressed into narrow gaps.)

The floor in the rest of the bathroom will get the same tile and grout color.  I expect to alternate between putting tile on the shower walls, and tile on the bathroom floor.  Probably not logical, but the change is nice.