Project: Van Aartsen Residence, North Brisbane

Project Description:

This home is an innovative prototype towards a more sustainable future.

The Van Aartsen Residence, on the edge of bushland in North Brisbane, is a luxury 440m² house with four bedrooms (all ensuited), granny flat, rumpus room, double garage and workshop, constructed from primarily tilt-up concrete walls. This not only ensured a tight schedule was successfully met, but served as efficient retaining walls for the semi-submerged lower ground floor containing the workshop and rumpus rooms.

The external walls were sunken into the thermal mass of the earth. Coupled with an integrally ducted and computerized mass ventilation system the design successfully achieved the client's brief of negligible energy consumption as traditional air conditioning was not required. A comfortable temperature range of 19 to 24°C was achieved throughout the year. Computerized system uses cold night or warm day air to manipulate the mass temperature and thus the internal air temperatures based on the principles of thermal inertia.

Attention was given to the principles of passive solar design. Additional protection from the western sun was achieved through the use of a living wall planted with indigenous flowering creepers. The use of natural day lighting, compact fluorescent and LED lighting and energy efficient appliances reduced the need for electricity use from the norm. The remaining short fall is covered by the use of a grid connected photovoltaic array. A single 750mm wide precast concrete gutter, servicing the 280m² roof and single 300mm diameter downpipe, efficiently collects rainwater and even dew. An attached polyethylene rainwater tank is used to supply both garden and home of all water, through a monitored system of filtration and purification producing potable water in excess of the relevant standards. This system is backed up by a mostly unused city council water main connection.

Household organic waste from the kitchen and garden is recycled in composting facilities, along with nutrients from a small chicken aviary, and used in a productive vegetable garden.

The building was completed in a tight construction program at surprisingly low capital costs, as compared to traditional design and construction methods. The heavy concrete structure, which is virtually impervious to the challenging soil conditions of the area, ensures excellent longevity. The various energy and water innovations, leading to measurable reductions in capital and running costs, makes the building an interesting prototype towards a more sustainable future.