Possibly doing a thermal efficiency makeover as well?

I had a 60's house with warm air heating which was ducted under the floors but I wanted insulated concrete floors with piped underfloor heating. The necessary works left the place looking like it had been bombed! Sleeper walls, floor joists and untold galvanised ducting out and tons of concrete, piles of insulation and miles of pipework in. It also gave me the opportunity to lower the finished floor level thereby increasing the ceiling height of the gound floor, which was probably the most beneficial and worthwhile part of the deal.