The brief was to create a home that could cater to a growing family of 5, as well as leaving as little impact on the planet as possible. To care for children into adulthood, and adults into old age. While going off-grid wasn’t a requirement, reducing the impact on resources was important, and exploring sustainable building at every step. Creating a home that feels comfortable and familiar to the occupants was of greater priority than what the exterior looked like.

The shell of the house is very simple – driven heavily by an efficient structure and a warm, airtight envelope. The interior is where the focus lies – simple, familiar materials make the house feel like it’s always been there. The central void is the real luxury, and focal point, of the house, playing with form and light, compression and release – it connects the interior to the envelope.

Located at the bottom of a valley, parts of the site were very wet. Tall existing trees on the northern boundary, and the desire to maximise solar gain for PVs were also a factor in site placement. The neighbouring houses all had low fences and a welcoming feel, so there was a desire to maintain this, and not impose an aggressive, modern house into the area. These factors all combined to push the house as far back on the site as possible. Timber piles float the house over the wettest parts of land, the PV panels are not shaded by the large trees, and the house recedes behind landscaping and distance to maintain the friendly feeling of the street.

Maximising north facing roof was a priority, so orientating the house across the site was the natural inclination. However, with a 5m setback from the adjacent stormwater drain, the buildable area of the site was narrower than it appears. Part of the brief was to use a structurally simple and robust form, which meant a small footprint and two stories. These constraints formed a tight envelope, which actually suited the brief well as it helped to focus on the bigger ideas of the project.

The building location also provided for a secondary, long-term desire to allow for enough space for smaller standalone dwelling units to be added for elderly (or younger) relatives in the future, if required.

The Living Building Challenge was an inspiration for the project, and initially a Materials Petal considered. While this wasn’t pursued, the principles of Red List Free and locally sourced were still followed.

The structure is SIPS panels, with a minimal amount of steel, on hollow timber piles. No concrete was used. The SIPS selected are from Cromwell, which at the time of design were the most locally available option. The cladding is douglas fir with a natural coating chosen to require minimal recoatings. A warmroof on timber rafters, and double-glazed aluminium joinery completes the enclosure.

The interior finishes are selected for their durability, familiarity and timelessness – a simple palette of cork flooring, natural timber accents, and tiles. Upstairs, PVC-free commercial carpet tiles provide a patchwork that the occupants can play with over time.

Engco Structural Engineers: Julian Addington and Tim Niven

Photography by Jason Mann Photography