Externally tiled window cills

[ClockPie]

Hi

We have a 1930s house and outside the window cills are tiled and deteriorated over the years, and painted (badly). Of course, previous owners have put in uPVC windows so would expect them to be overlapped a bit (!). They seem to be slightly shallower than the external brick face. Maybe 160mm wide, 130-140mm deep (to window at least) and 15mm thick.

Just curious on how I should go about this.

is it a case of simply removing the old tiles, and mortaring in new ones? Seems to be staggered double layer. So mortar 2nd layer on top and then just seal the edges? (Or proper tile adhesive?)

Any specific tiles for this job? Or just, say 150x150 quarry tiles?

Any tips most welcome as I'm sure there is a correct way!

(Good/appropriate alternatives considered: e.g. get made (or make) single piece cills? )

 

[foxhole]

Have 30’s property , my builder used same tile as on my roof to match, two layers (mortar fixed).

 

[ClockPie]

thanks.
We have double romans - and the wobbly bits wouldn't look right for us