What to do with old back door sill in conservatory

[simonk]

Hi all.
Did a quote tonight. Conservatory floor. Customer wants insulation , then underfloor heating, then tiles. Will raise the floor about 40mm in total I reckon. No problem, except the conservatory was built on the back of the house and the old plastic door sills are 20mm proud of the new concrete conservatory floor. What do I do with the old door sill ?
Do I
1) tile upto the sill and cover sill with a strip of wood to hide the old sill
2) tile over the sill and hope the plastic will support the tile above it
3) remove the sill, even though not sure what is under it and make good
4) other ?

Cheers
Simon

 

[Concept PHT]

Remove the sill and tile up to the door frame 🙂

 

[Leatherface]

Remove sill - make good - tile up to door frame leaving gap for expansion - Silicon 🙂