En-suite in a pitched roof, proposed heights

[Moonshine]

I am looking to put a en-suite in an existing bedroom in a pitched roof.

 

The en-suite is based on a 1200 x 900 shower tray with cut corner to minimise the intrusion into the bedroom, with the door opening inwards to the shower.

 

Below is a sketch of the space as i see it working, with the ceiling heights marked on in the key areas, i think that the heights are o.k (they may come down by 50mm for more insulation in roof void). I am not too sure about the clearance above the toilet, any thoughts or guidance on minimum heights, and laying out a en-suite in a eave?