Curb or threshold 4 x 6 or use 3 (2x4's)
10 - 12"
Solid backing between studs
Weep holes
Drain bolts
Cast iron drain phlange
1/4" per foot from wall edge to drain phlange edge AS FLUSH AS POSSIBLE TO THE FLAT PORTION OF THE BOTTOM PHLANGE
Small shower pan with ponywall by tub ledge.  Hot mop will wrap up the ponywall & go out part way onto the tub deck.  Solid blocking should be flush with the studs with no gaps

Sloping 1/4" per foot from wall edge to drain phlange edg and as flush as possible to the flat portion of the bottom phlange.
Click photo to enlarge
Angle pan with ponywall & tub deck
Solid blocking between studs, sloped with plywood
Seat pan with ponywall & tub deck
This photo shows 3/8" plywood backing nailed to studs.  Green board is already installed leaving plywood areas for us to hot mop to.
Click photo to enlarge

Here are some pictures. 

We hope that they will be helpful to you in setting up your shower to be hot mopped.

Standard threshold/curb height is approx. 6” to 8” – usually (3 each) 2x4’s nailed flat or a 4x6 nailed to the floor.  Solid wood backing set flush with studs or 1/4” – 3/8” plywood nailed to studs should start at the face of the curb and run from the floor up the wall 10” to 12”.  On seat pans use a similar wood backing on the wall area approximately 6” to 8” above the seat and 4” to 6” on sides of the seat where it touches the walls.  Seats should be made of wood & plywood or chipboard with no sheetrock on them.

Floors should slope toward the drain 1/4” to the foot.  On a wood sub-floor slope can be built using 1/2” to 5/8” plywood or pressed wood cut to fit inside shower floor area.  Cut a hole for the drain approx. 5-1/2” to 6” in diameter.  Then cut plywood from corner to corner diagonally making 4 triangular pieces.  Nail appropriate lengths of stripping to the floor around the edges of the pan (height of stripping varies as the distance to the drain increases or decreases).  Lay the triangular plywood pieces onto the shower floor using stripping to build the slope then nail it in tight.  Sometimes additional shims are needed under the sloping floor to keep the floor from giving too much.   A cement slab floor can be sloped using mortar.

The drain phalange assembly should be set up making sure the flat portion of the bottom phalange of the drain is set flush to the sloping floor surface.  Drain assembly should also be level.

We hope this information is helpful.  If you have any questions give us a call


Cast iron drain phlange set flush to plywood sloped floor
Small shower with 1/4" plywood backing.
Same shower - HOT MOPPED 
Extra large custom shower pan with angled seat and extra wide curb areas
Plywood backing nailed to studs
Coversheet extending onto floor area as requested by our customer. 
Unique shapes & large sizes are accommodated well using the hot mopping method of waterproofing.
Click photo to enlarge
Click photo to enlarge
Click photo to enlarge