The right tools are needed to do a proper energy modelling job. For Certified Passive Houses, using the Passive House Planning Package (PHPP) is mandatory. It is the only energy modelling tool in the world that has successfully been tested against real-world results on a large number of projects (see here for some examples). Thousands of Certified Passive Houses deliver results very close to the modelling expectations. Other modelling tools are clearly not performing that well, or have never been tested. […]
It is impossible to achieve an indoor environment that can be categorised as comfortable by international standards (e.g. ASHRAE 55 or ISO 7730) with an indoor air temperature of only 18°C.
Despite the myth, there is no indication that Kiwis are more tolerant to colder temperatures than people elsewhere in the world, which should not come as a surprise, as many of us were born overseas, or grew up in far away places. In fact, several NZ studies suggest that if Kiwis are capable, technically and financially, to heat their homes to the degree Americans and Europeans are accustomed to, they will (Fyfe, 2005; Howden-Chapman et al, 2009). […]