Home Extension Self Build - Block and Beam Flooring 

It’s a requirement for heavy clay soils. There needs to be a separation between the ground and the subfloor (in my case 225mm). I’ve also got a tree nearby, which affects the moisture content of the clay soil. Clay soils can heave and crack your concrete slab. … so they say.

🤣🤣 Yes I do do this sometimes. Not sure why I didn’t this time. 🤔

Yes. 150mm PIR insulation, then a damp proof membrane, then 65mm screed. Then finished floor.

@@doityourselfdavecheers, I thought that was the case

Thanks 👍