While there are a multitude of tools available in the Australian market for low-energy standards, Passivhaus is the strongest yet to ensure the realisation of a high-performance building. Many design stage tools and codes, including NatHERS, the NCC and NABERS, have shortfalls, including idealised assumptions and no guarantee or sufficient checks of the built product matching the design (State of South Australia, 2014). Although Passivhaus uses what many would regard as ‘just an Excel tool’ (Microsoft), the basis of the Passive House Planning Package (PHPP) is in pure building physics and there are numerous case studies (Feist 2007, Oram 2011) that have verified the predicted result as being a precise representation of the as-built product.
The Passivhaus design standard is effectively a guarantee of build quality, and being an ’as-built’ standard (certified once the building is complete) it has marked benefits over the often applied design-only standards prevalent among Australian building codes and tools. The end result is the only one that matters so it is paramount that the whole process is managed smoothly to ensure success.