Underfloor heating

PKWATERFORD

We are renovating an old house. We have poured the subfloors and have all the internal walls etc built.

Now we are looking at putting down the insulation and underfloor heating pipes and the concrete in the floor. We are planning on 4" of insulation, the u/f heating pipes then 3" of concrete, then stone slabs on the floor. The stone slabs are approx 2" thick.

Will the u/f heating work efficiently with this setup or will I need to reduce the concrete by an inch or so?

sinnerboy

2 x 60 mm layers of insulation is typically required - so yes that "extra inch" would be good to find

Alternatively if you use an "easy - pour screed" you could reduced it to 40mm

PKWATERFORD

So you think that I would be better to go with 2" of concrete and then the stone slabs on the floor? I would imagine that this would be good enough

PKWATERFORD

I should have mentioned that easy screed would be the dream but the only ones that cover this area have articulated lorries and the road we are on was not designed with this in mind

sinnerboy

50mm ordinary concrete screed is liable to fail - crack

The 2 x 60mm is required under 2008 regs for new builds but not refurb . And your 100mm would have been fine even for new under 2005 regs

Having said that - it is in your long term interest to place more not less insulation