Fixing threshold bar to screed

[WWilts]

UFH with Cemfloor screed. Laying SPC click vinyl flooring above. Threshold between rooms has T-bar that click onto U-shaped rail.

Q: What adhesive to use for fixing the U-rail to the screed below?

 

PS Holes in the U rail are miniscule, & screws might go into the UFH pipes

Edited August 1, 2022 by WWilts

[Makeitstop]

Gripfill. Once stuck down, absolutely solid.