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  1. Spanish

    Spanish GSR

    retrofit of ufh preferably without tearing up slab, but would like to make use of the generated heat without losing it to the slab what is the best solution/insulation

    in here because will be rung of ground source heat pump

  2. Ermintrude

    Ermintrude Plumber GSR

    U can get thin floor stuff but it's a shortcut....
  3. Nostrum

    Nostrum Plumber GSR

    Why a short cut? Lower thermal mass, quicker warm up times.

    Watch the pipe runs with low build up systems, smaller diameter pipe with higher heat pump flow rates = careful planning required. Make sure whoever you choose for UFH knows it's for a heat pump.
  4. Worcester

    Worcester Plumber

    25mm of the super insulated celotex equivalent to 100mm of normal, then the thinnest that I know of is: LoPro10 - Nu-Heat - Underfloor heating and renewables the next thinnest is Overlay Lite Underfloor Heating

    Managing the flow and head loss using a GSHP will be critical, you will need as a minimum a buffer or low loss header, my preference would always be for a buffer, a good control system (heatmiser) someone needs to do the heat loss calcs to make sure that either of the above solutions can deliver what you need. All ufh works better with a thermal mass, though if you ain't got it then no choice. (Flow rate, flow temperate, head loss, heat loss, emitter output; Simples :) )

    Get this: CIBSE - Underfloor Heating: Design & Installation (Domestic Building Services Panel) 2012 it's only £18.50 and will save a fortune in mistakes.
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  5. missplumb

    missplumb Plumber

    i was gonna suggest the overlay lite, been looking at it for a project im starting working on.
  6. paulusgg

    paulusgg GSR

    I run UFH from a GSHP all fitted retrospectively in a 1960 bungalow. Admittedly I did break up the existing screed to fit the UFH so as not to lose too much floor to ceiling height, The floor make up is as follows 30mm celotex with 16mm pipes in cliprails. Between the pipes short lengths of 25x50 batten as a guide for a weakish screed(for the thermal mass) and finally 22mm chipboard laid over as a floating floor.

    The system has been in and running for the past ten years delivering loads of hot water and the house is nice and warm. FYI I installed a IVT Greenline GSHP
  7. Spanish

    Spanish GSR

    Hey all, many thanks for all of the input, apologies for the delayed response, I have been looking at new ventures and thinking of getting into laying and polishing concrete slabs as a add on to my business, purely based on that is what I want my home floors to be and as with everything I believe it cost effective to qualify/buy in the kit and diy then use it to make money...
  8. Sparkgap

    Sparkgap Active Member

    What he said. Warmup also do a pretty thin system Total-16 Hydronic Underfloor Heating System by Warmup | Warmup

    You also need to remember that UFH output depends to some extent on floor covering. Roughly 70-100W/sq.m means it might not be suitable for older properties or rooms with large heat losses, then again I might be teaching granny to suck eggs ;)
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