My builder is meant to be laying underfloor heating tomorrow before he goes off on holidays the following day. He was meant to put a tarpaulin over the roof to make the slab water tight in anticipation of the rain in London but did not. Instead he covered with kingspan insulation.
Given the rain water will just sit on top of the insulation and seep through underneath will he be able to lay the underfloor heating tomorrow? Polished concrete is going on top the following week.