Home Forums General Discussion Underfloor insulation mandatory? Reply To: Underfloor insulation mandatory?

Eion Scott

Ian is correct, and the calculation method is one of the “cheats” that designers can access to implement poor insulation, usually done though to bypass the schedule method requirement for double glazing. That’s a complete disservice to clients, and I’m now getting single-glazed homes that were built in the mid-2000s that the client is wanting to retrofit double glazing at huge additional cost. Re floors, the schedule method requires R1.3, which can be achieved by an uninsulated slab, but will depend on the complexity of the footprint (calculated via perimeter to area ratio). Without being blinded by the science, the best advice is to have new builds insulated under the slab and with perimeter (edge) insulation to achieve passive solar design/thermal mass. Wooden floor houses will need to be insulated to achieve R1.3.