Copper pipes on block and beam

[Cookie123]

Hi all. New to this. I Will Try and explain best I can.
Large New build (2.5yrs old) with block and beam flooring.
Then Membrane
Then celotex
Then membrane
Wet system underfloor heating
In approx 2-3” of screed I think
Then tiled throughout
15mm Hot and cold copper pipes, felt lagged running from the boiler through the kitchen through the hallway then to a downstairs WC. Approx 15 mtr away from the boiler

Should they be sitting on top the block and beam or on top of the first membrane /DPC ?

Is there a right and wrong approach
Are there building regs for this ?

 

[ShaunCorbs]

ideally should be above dpc

 

[Lou]

Hi How did you get on with this?