Zoning UFH in mix of solid and suspended floor.

[darbon]

Hi All,

I'm looking for some advice regarding a new water UFH layout.

I am looking at a 6 zone manifold system where 3 of the zones are solid floor/70mm screed/tiles, the other 3 zones are suspended floor/25mm PUG mix/no more ply/tiles. The manifold is located within the suspended floor zones. I'm not interested in individually controlling zones and I am happy to just work with balancing the heat with the manifold and a simple on/off room thermostat to control the whole UFH system. However... I acknowledge that by having the two different floor constructions, balancing everything on the manifold would be tricky because of different thicknesses of screed and warmup times etc.

Question 1: What would be the simplest (cost effective) way of the splitting the system into two controlled zones (3+3), solid floor and suspended floor? Would it be fitting a simple floor thermostat somewhere in each of the two zones, which then activates the three actuators at the same time? The three zones could then be balanced at the manifold. Or is there a better way?

Question 2: Is there any good reason why I shouldn't run the pipes between the solid floor zones and manifold UNDER the suspended floor rather than through the suspended floor screed? They would of course be lagged! My reasoning would be that if the solid floor pipes ran through the suspended zone screed, they would mess with the separate controlling of the two zones and also run through an expansion joint between the two zones. If I was to run them under the floor, they could simply pop up into the screed of their own zone.

Thanks in advance.
Dan