Thanks again this is great help, there still building on our site so I had a nosy expecting to find pour standards but it semp quite good there were no obvious gaps, all insulation in place according to details it's isover rd party wall roll, they hadn't put sealing around the joist were they enter but I have since done this and it's made no difference, there should be a 75mm cavity, 9.8 kg/m2 gypsom board on dabs but they havnt done a solid ribbon as I went in the loft with a rod and could poke it down in many places also the daps are to far apart, there no render parge coat required in the details and the block density says 1350-1600kg/m3 or plasma aglite ultima, they apar to be concrete and not thermolight though,
Il try to find more details but hope this helps, this is realy appreciated