As with all our projects at MDC Architects, our designs commence with a consideration of some fundamental principles- How can we arrange the spaces to benefit from solar passive design? And how do we utilise this orientation to heat and cool the internal spaces naturally, without the reliance on mechanical systems? This stems from a comprehensive understanding we have of Perth and the South West’s environmental context.

The term ‘Passivhaus’ is becoming more common within design and construction in Australia, facilitated by an increased awareness of our environmental footprint. Conceived in Europe, Passivhaus is essentially a set of principles that, when adopted, will create an energy efficient home with high quality internal air. This is achieved through; well-sealed junctions in materials and little to no air ‘leakage’, heat recovery systems, pre-conditioned air ventilation systems and high resistance glazing, to name a few. It is effectively a systemised means of controlling your internal living environment to reduce the energy demand required to maintain a stable living environment. The catch: it is reliant on the continued use of mechanical systems.

Australia, and specifically Perth, has a climate that differs significantly from the European climate where Passivhaus was conceived; one that encourages the use of our outdoor spaces, opening our rooms to the gardens for natural ventilation. Our winters are relatively mild and, given the abundance of sunshine we receive during the winter months (on average about 60% of our total daytime hours), we already have ample access to the most sustainable means of heating our homes. In short, if we design our homes to be more responsive to our immediate climate, we have the capacity to heat and cool our spaces passively rather than mechanically. Sure, there may be instances where an air conditioner is desirable when we get to our extremes though by no means should we be reliant on it for a comfortable internal environment.

If we orient our homes to the north to benefit from passive solar design and cross ventilation, we then have a far greater means of controlling and managing the temperatures and comfort level of our internal spaces.  Thermal mass enables our homes to act as large stores of heat and coolth and if designed correctly, will store these during the winter and summer months respectively, to be released when needed most. This in-built heating and cooling system encourages our homes to be operable, to let breeze flow through and to let sunshine in during winter.

As lightweight, timber frame construction becomes more commonplace, the argument to adopt Passivhaus principles is increasingly more relevant due to the lack of thermal mass within the home. Conversely, this lack of thermal mass also means it is far quicker to remove the internal air temperature by cross-ventilating the spaces. From our perspective, there is no right or wrong answer to this debate as both sides are inherently a positive step forwards in increasing the quality of our homes and the liveability of their spaces.