A Passive House Retrofit: Delivering Energy Efficiency, Comfort, & Indoor Air Quality in Australian Buildings

A Passive House Retrofit: Delivering Energy Efficiency, Comfort, & Indoor Air Quality in Australian Buildings

Authors:

Joel Seagren and Clare Parry

Organisation of Presenter:

Fantech

Abstract:

Passive House is a building design and performance methodology centred around delivering improved comfort and indoor air quality to buildings worldwide, with verified performance results within 1% of modelled targets across thousands of projects. While indoor comfort and occupant health and wellbeing are the focus, one of the co-benefits inherent to the approach is substantially improved energy efficiency (up to 90% less than average building stock) through the dramatic reduction in heating and cooling requirements. Designing and constructing buildings to Passive House standard requires small but significant shifts in thinking around several key building attributes, a significant one being air tightness. The fail-safe approach used in Passive House buildings, that goes hand in hand with substantially-improved airtightness, is ensuring healthy indoor air quality is maintained through the use of Mechanical Ventilation and Heat Recovery (MVHR). This system works on the premise of controlling air flows throughout a building, introducing fresh air whilst ensuring optimal comfort and very high levels of energy efficiency are maintained. This article draws on learnings from Australia’s first Passive House Certified retrofit (EnerPHit) in 2016, a residential dwelling in Victoria. It examines the measures taken to reach the performance targets. This project had a design average annual heating and cooling demand of 14kWh/m2a and 3kWh/m2a respectively (based on Passive House comfort bands of 20-25° year-round). Measured building temperature data in winter demonstrated that comfort levels were maintained with very little heating input. This has resulted in energy savings of YY kWh/mJ (=$ZZ) (As this is a recently completed and certified project, data collection is ongoing and therefore final energy saving data is still being collated).