Hi. I'm considering buying a house to refurb and sell on. The roof is knackered and the ceilings of the 80s/90s loft conversion will need to come down and be replaced.

Am I obliged to fit current building regs spec insulation in the void between roof and ceiling, or can I refit to same specification as before? I'm concerned that I might lose some headroom if a whacking great thick layer of insulation is needed.

Cheers.

Terry.