While discussing sustainable home design with others, I realised the word "passive" mu;st be used carefully. Passive solar design is different to Passive House design. It's important to understand the differences and similarities.
While the indoor temperature felt comfortable during hot summer days, I was left with the nagging feeling that wishful thinking was keeping me cool. Passive solar design should minimise the need for mechanical cooling for everything but a run of very hot days. Temperature monitoring data confirmed this is the case for our design.
As soon as the team finished Unit 1 in late 2018, work started on the site for Unit 2. A lot of time and effort went into the groundwork for a stiffened raft slab. During one busy day, the concrete was poured and the slab finished.
During Unit 1 construction, the team showed that an offgrid power system could meet the electrical requirements for all but the most demanding users. Based on that experience, the system was reassembled to power Unit 2 and 3 construction.
Insulating the concrete slab edge reduces the heat lost from the thermal mass during winter. There are a variety of ways to install the insulation along with the termite barrier. After considering the likely cost/benefit, our design uses a garden bed to cover exposed concrete edges.
Using heat pump technology for both the reverse cycle air conditioner and the hot water system is an efficient way to meet those needs. Despite the warm weather, the air conditioner is yet to be fully tested as the passive cooling features in the house have kept this heat pump on standby duty.
Building the deck for Unit 1 from sustainable decking materials was a requirement. Creating an artful privacy screen from reclaimed timber offcuts was the icing on the cake. The process highlighted what can be achieved with a commitment to sustainable building practices.
After years of talking about living in a home based on sustainable design principles, we are now living the dream. With the first house nearly finished, we took the opportunity to move in and get our first impression of a new lifestyle. Early indications are the design is meeting our expectations.