1st fix under floor or in the ceiling

[Buzz]

A basic question before i have a site meeting with the plumbers we have a block and beam floor with 225mmm to dpc to be filled with insulation UFH and screed , although it is a bungalow we do not have any roof trusses we have posi joists at celling level and a cut roof above so the question is where does the 1st fix pluming go we already have the waste pipes in through the floor but what about the hot and cold water pipes? , on the floor and then up through the insulation and screed or through the joists and down the walls ? is it personal preference or do they have to go into the floor .  

[Dave Jones]

not in floor. walls/stud/ceilings.

[joe90]

24 minutes ago, Dave Jones said:

not in floor. walls/stud/ceilings.

Unless you want an island in the kitchen with services!

[Russell griffiths]

In the ceiling, it is far easier to cut a hole in a plasterboard ceiling to fix a problem then to dig up a floor. 

[Buzz]

Thanks for the replies,  it made more sense to me to run them above rather than below for the very reason @Russell griffithspoints out .