Tomorrow i intend to lay down the heat wire system on top of the homelux membrane i have just laid.I intended to cover this with slc only on the flat floor area but am worried about the difference in height that will be created by laying 12mm Travertine on a solid bed on top of this because i am putting 10mm Travertine 50mm mosaics on the tray area.Obviously the tray area will need to be built up as the mosaic's are best laid on a thin bed,whats the best course of action to achieve this? Thanks.

The floor I would have, ufh, slc, ditra or dura then lay travortine

hi peejay if the tray is the same height as the floor with the htg fitted?. fit outside the tray first with the 12mm trav let it dry then skim the edge of the tray up slightly with rapidset spf to allow for the couple of mil diffrence .and you can use a thicker notch trowel with these mosaics because they are 10mm thick for extra build up if u need to. if any adhesive comes through the mosaic tile joints get an old toothbrush and clean the joints as you go hope this helps

Are there any recommendations as to what slc to use with ufh. Does it need to be flexible if the floor is stable (2x18mm cross bonded screwed ply), are there any thermal issues I should be aware of.

Yes it needs to be suitable for timber overlay..