Boilers and Heating
Ground source heat pump distributor (internal)
Micro-Combined Heat and Power / Biomass
Stairs and Staircases
Unimproved loft space
Where more than 25 per cent of a ceiling below a cold loft space or flat roof is being replaced then the Building Regulations would normally apply, and the thermal insulation of that ceiling would normally have to be improved.
Learn more on the Planning Portal