Thanks for the superb information. Now i'm tempted to go for it upstairs as well. Seems critical that it is insulated beneath even upstairs? If air tightness is done well and based on the theory that heat rises, is this a real issue? Certainely downstairs I would insulate. In fact newer regs call for approx 100mm polystyrene or 60mm celotex, depends on p/a =perimeter (external walls)/ area of floor. If i went for one circuit downstairs, with numerous zones contined within, one circuit upstairs and seperate circuit for hot water then I would need a three circuit programmer. Is there such a beast?
Its all the regulations require. Its a suspended floor though with about
9" of foamed concrete block under that. and 4" of screed over the top.
So about equivalent to a double brick wall with fibreglass batts down it.
If the wind doesn't blow, it is fine., but if the wind does, it is not too good with the underfloor cavity being all ventilated etc.
I was surprised too, and went into the regs in detail. Essentially - and its very true for a solid floor on teh earth - teh heat loss is far less than you might expect because the conductivity through the ground is actually quite low.
I.e. you do indeed build up a pool of warm soil under the average house, and the heat has to travel through a lot of soil to get to the soil surface qwhere its radiated away.
Sadly with block and beam, unless its calm, the wind pulls the warmer air from under the house..
And of couyrse the regs don't account specifically for UFH, where the floor is the warmest place.
So on reflection, I'd go thicker. But you don't have to by (building) law.
No. Lack of isnulation upstairs will merely result in warm ceilings downstairs. The overall energy loss of teh house will not be affected, but of course, you want teh heat to go upwards to work at all,so you need to fit that insulation, BUT its not MANDATORY.
I have a friend with a bathroom with CH pipes under teh floor - its chip and slate over - and that is heated accidentally, but nicely, by the hot water pipes.
All you actually need to do is fit rockwool and then run pipes between joists. I am not particularly convinced by the use of the aluminium reflectors. But I suppose they add a little.
Ask peter parry.
If air tightness is done well and based on the theory that
Its one _zone_ and numerous _circuits_.
Yup. I have one. Hard to find but not impossible.
You also need and auxiliary pump and temp reducing valve. And a relay somewhere.
I got the manifold for all the circuits, the pup and the reducing valve as a unit from polyplumb - its lovely because each circuit has a flow meter on it - siple but effective. I made my own control box as well. Loads of wires and screw connectors and a relay.
You would need to possibly fit eiher two auxiliray pumps and two manifolds to handle teh two zones, or a few motorsised valves to have tow totally independent zones. The ployplmb maqnfolds can have actuators added to function on a per CIRCUIT basis, but if you have 6-8 circuits upstairs, it gets expensive.
Don't use KEE Tripple tube, when it goes wrong you find the guarentee is issued by an old guy who lives in the wilds of ireland, and doesn't have a phone - oh and if you do find him - the company name of the top of the garentee is a dud.
And if the maker of KEE tripple tube wants to sue me over this statement then I'll see you in court, and I'll win.
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.