Tiling floor, uneven

[ss]

Having plyed the shower room floor I now find one section about 1 sq metre is off the level by around 4mm. Too late to level under the ply. Should I level this up with tile cement when tiling or level up before tiling with product at hand:

Floor tile adhesive, Mastercreet cement, One coat plaster

[Tim Watts]

If you are tiling the ply, you can put down a layer of the same adhesive and use that to correct the slope. Let of harden overnight then tile as normal.

Did the same here were 2 rooms had a 15mm step in the passageway between them (narrow thankfully) - tile adhesive used to form a 2' long ramp (that's invisible to all but a 6' level!)

[The Natural Philosopher]

if you use rapid set, when tiling

[ss]

Thanks all for the replies.