haythorn_1

Thanks @Kelvin, useful. Thats more like the kind of price level I was expecting. Nordan are on my list.

Starting the process of getting quotes from a few recommended suppliers. Just got my first one from the local distributor of Rationel and nearly fell off my chair. Worked out at £1997 per m2. Quote is for 38m2 mostly of windows with a few French doors all in formaplus triple glazed with glazing bars. I had requested the order be split in two as this is a refurb in stages, if I combine to one it drops by ~10%. Still seems way beyond what I would have expected for Rationel. Hopefully some of the others are more reasonable.

@Thorfun that is what I have done on my test circuit and it works. There is a slight delay from pressing the switch to the light turning on, which is a bit annoying.

Plant room is about 5m from ASHP location. So could run pipes in the ceiling joists to the exterior wall or below the foundations. Through the foundations seems much more expensive but I guess it removes the need for a wall penetration.

If doing strip foundations would the pre-insulated pipe need to go below the footing? If so how far below? Must need a deep trench!

This looks much cheaper than the Rauvitherm, is there much difference?

Need to be careful of the u value. For the moondraught it seems the standard one is 1.66 w/m2. It is quite a small area though.

What is the benefit of doing a parge coat vs VCL? Is it just cheaper and quicker?

Global lumber prices have been falling so makes sense. Now almost back to where they were in 2019

I’m still a way off doing anything, just at research / planning stage

Interested to see how you get on @Sophiae. I asked a similar question a few months ago and from the responses it seemed it would be possible to match the level of two concrete slabs poured separately:

Thanks all. Sounds like it is possible then. The only bit I should have been clearer on is the doorway is not an existing doorway, it will need to be knocked through. I was thinking this would be done after the extension slab has been built.

And then flooring can just go straight over the insulation board? Definitely dont want that. I was trying to find a thread with someone doing the same but couldn’t find one. Any suggestions on how best to avoid? I know with screed they use those level measuring stands.

I am planning an extension at the back of my house and from research here I intend to go down the insulated slab route with no screed, so the UFH would be in the concrete slab and then the slab is the finished floor level. The existing first floor has a concrete slab (I suspect it’s uninsulated as was built in 1950s) which I plan to dig up and then lay using same lay up as extension. I plan to lay the slabs separately as my intention is to live in the old house whilst the extension is built, then move into it and redo the old part. The only joining point of the two slabs is a doorway which I would want to have continuous flooring through (LVT). How possible is it to lay two concrete slabs with the same floor level?