XPS or hard face insulation

[foresttowndiy]

Gents,
I'm finally ready to lay my kitchen floor and want insulation boards down 1st. I was going to use xps, the blue foam sheets but I know tilers don't like tiling if xps sheets are used.
I only have a maximum of 30mm from my existing concrete floor to the top of the tiles. My tiles are 10mm thick and 3 sizes, 165, 333 and 500sq so I've got to use a 20mm half round trowel. How thick will the finished bed be under the tiles?
I'm laying a ufh heat mesh down and will slc that flush to top of wire to make tiling easier, the slc will/should not add any height so thats another 2-3mm (prowarm mat).
I have a choice of 6 or 10mm insulation sheets and might go to hard faced instead of xps. What size notch trowel should I use for the adhesive? How thick a bed will it give me, I'm hoping for 2mm when bedded down, do the insulation sheets need much of a bed under them to stick them down?
Sorry if there's lots of questions in one post!

 

[AdamCH]

20 mm half round will give you 8/10mm bed. 2mm bed is not possible.

Use a good tiling insulation board like Marmox. Forget XPS.

You aren't going to get insulation 10mm + UFH 5mm + tiles 10mm + adhesive in at 30mm. Either forget UFH or plan on a thicker floor.

Marmox will be laid on a 6mm trowel & will give a 3mm bed. Less than 10mm insulation won't be worth it.