The area between the drain and perimeter must be filled with Deck Mud ....packed and then scraped flat and true with at least a 1/4" drop per linear foot.
The mortar bed is complete. Now we switch to Mortar-Mix to apply Fat-Mud onto the curb.
I use whatever "Props" will do the job. In this case I'm using one of my straight edges to flatten mortar against the outside surface of the curb. Using a measuring tape I can ensure that the curb is running parallel to the wall.
The mud work for the shower pan is complete. The next stage is to install the Kerdi waterproof membrane.
The mud for the curb must set up for an hour or more before I can safely begin scraping it flat and level.
Fat Mud is made from bags of Masonry-Mix which is also better know as Mortar-Mix. It has a finer sand than Sand-Mix, has lime in its ingredients which gives it the ability to cling and it's also mixed wetter than the mix used for Deck-Mud.
Getting ready to install Kerdi over my sloped mortar bed.
The Kerdi should be pressed into the mortar for complete coverage.
My customer provided the heating system. It's a 3" spacing for this job, but ideally a 2" spacing is recommended for bathrooms by most manufacturers.
I'll need at least 1 more application of mortar ... possibly 2 more to get it perfect.
Ditra will be installed over top.
In know that Schluter states to use unmodified mortar over its Kerdi membrane .... but I'm using a good quality modified for this pebble floor. The stones are small enough to allow curing of the mortar.
At the end of the day I'm applying 1 more final coat of medium bed mortar to level over the heating cables.
Ditra isolation membrane has been installed over the heating system.