Hi all, in the process of planning wet UFH on the ground floor of our house. We have suspended joists (5x2). Looking at options, im leaning towards running the pipes on 30-50mm of pir (battened) and then running 20-25mm of dry pack 8:1 sand cement over the pipes before boarding with chipboard and floor covering. My question is whether i should run a dmp over the dry pack between the chipboard board to stop any moisture from the sand getting to the board. Any thoughts? Not sure how 8:1 sets, should i board straight away or leave it a couple of days? any other considerations? Ive checked the dead loading and we have enough sleeper walls for that to not be an issue. is this the best way considering costs and thermal performance? cheers
Thanks Scooterdemon - a preformed insulation board was my initial thought but people have said that the thermal performance would be better with a dry pack. i was looking at cement boards and preformed insualtion instead of chipboard and screed but the costs become prohibitive.
Its around 35sm across 2 rooms (kitchen and dining) and a hall way. I have looked at alum plates - again the issue for me is performance. This will be the only heat source in the rooms so want to maximise output. would you suggest alum offer the right balance of performance and cost? Labour time would be pretty much equal across all methods. cheers
My own lounge, 8m x 5m has UFH on a suspended floor using speader plates. It works very well. Use te preformed boards, with an extra layer of Celotex or similar below.
I have aluminium spreader plates, with 100mm celotex underneath, 18mm caberboard on top, followed by LVT. Gets nice and hot pretty quickly, but cooling down is also the same. I was always under the impression a screed would hold heat longer after the heating is off?