Running water pipe under screed/UFH?

[BadgerBadger]

I'd like to sanity check a plumbing plan please!

 

Our kitchen is in a high vaulted space and quite a long way from the plant room / UVC.  So my options for pipework is 1) a convoluted route up through the loft, along a service void in the vaulted ceiling and back down wall to the kitchen or 2) a slightly bendy route, but somewhat shorter, route under the floor screed.

 

Floor buildup is beam & block, 140mm insulation and 55mm liquid screed with UFH.

 

Pipe runs will be single length of plastic pipe with no joints under floor, in narrow duct so they are theoretically replaceable to meet water regs.  My current thought is to put them in a channel in the insulation, with some thin insulation covering them to give a bit of separation from the screed/UFH.

 

Does that sound logical, or any other ideas?!

[Conor]

Yes, in a conduit within the insulation. 

[JohnMo]

All our cold pipes run below the insulation in the floor (200mmm PIR). They are in flexible conduit cast into our concrete subfloor.

 

Keep well away from UFH as you will have a breeding ground for bugs in the warm space. Also who wants warm 'cold' water.

 

Legionella growth chart - UFH temps are the correct temperature for slow and optimal growth dependent on flow temperature.

 

 

Edited August 18 by JohnMo

[BadgerBadger]

3 hours ago, JohnMo said:

All our cold pipes run below the insulation in the floor (200mmm PIR). They are in flexible conduit cast into our concrete subfloor.

 

Keep well away from UFH as you will have a breeding ground for bugs in the warm space. Also who wants warm 'cold' water.

 

Legionella growth chart - UFH temps are the correct temperature for slow and optimal growth dependent on flow temperature.

 

 

 

So are you on the "cold side" of your insulation? As you say, would be good to keep well away from UFH even though our flow temps would be relatively low.

 

I had though of running them pretty much on the beam & block, with majority of insulation over the top but was concerned about freezing.  That said, not sure if the beam & block would actually ever really get towards 0 degrees.

[JohnMo]

15 minutes ago, BadgerBadger said:

So are you on the "cold side" of your insulation?

Yes but a ground bearing slab.

With block and beam I would have some insulation below the pipes and plenty above.

 

18 minutes ago, BadgerBadger said:

That said, not sure if the beam & block would actually ever really get towards 0 degrees

Assume the space will be vented below B&B, so if cold outside the space below would be similar.

[BadgerBadger]

I think I'll aim for middle then!! 🤣 Thanks