K2 Apartments

Water

Rainwater is collected, treated and stored in rooftop tanks to supplement domestic supply. Grey water is recycled for gardening and toilet flushing.

Water-efficient fittings and fixtures such as AAA showerheads reduce water consumption, and water meters are installed in each unit to monitor water use and educate tenants. 'Water smart' gardens have been designed that need little water.

All these measures will reduce mains water use by approximately 53 per cent compared to an average apartment of similar size.

Materials

Materials were chosen because they were recyclable, robust, non-toxic, and did not produce much waste.

Timber was either reused or came from sustainable managed forests, and fly ash (a coal combustion product that is more durable and produces less greenhouse gas emissions than cement) was used instead of cement in concrete. Non-toxic paints and floor finishes were used, assuring high indoor air quality, while natural finishes reduce maintenance needs like painting and varnishing.

Energy use and solar power

Exposed concrete ceilings and heavy walls provide thermal mass to help maintain a stable temperature indoors, while insulation, double-glazed windows and shading prevent heat loss and gain. Energy-efficient fittings, such as fluorescent light bulbs, are installed throughout the apartments.

Summer

Cross-ventilation will cool the apartments and fans and ventilators will carry away built-up heat.

Winter

The buildings are oriented so that all units receive northern sun, reducing the need for heating. There are a limited number of windows on the south, east and west sides of the buildings to reduce heat loss through the glass. The buildings are well sealed and insulated, and screens beside the access balconies provide protection from the weather.

Solar power

Roof tops are angled to face the sun so that photovoltaic panels can collect the maximum amount of energy, and also provide some shade. Solar power heats at least 50 per cent of the buildings' hot water.

Landscaping

Approximately 20 per cent of the K2 site is dedicated to landscape gardens. 'Water smart' gardens drain water to areas where it is most needed, and filter stormwater before discharging it from the site. The gardens use drip irrigation from the grey water supply.

Mostly hardy native plants were chosen that suit Melbourne's dry conditions and the amount of sunlight in each space. A mixture of deciduous and evergreen trees was chosen to provide shade or allow sunlight in, as needed.