I recently had central heating installed in my 2 bedroom ground floor maisonette. We installed all the pipes in the channels which we dug in the concrete floor. I have covered all the pipes with insulation and now it is the time for refilling the channels and then covering all the floor with laminate/wood flooring.
I have cut some pipe insulation and fit them to the pipe just to keep some space for expansion and contraction; I am planning to put some sand (dried sand used for driveways) in the channels, say 2cm, and then fill them up with mortar.
My question is can I use mortar to fill the channels?