We value the sunshine and rainwater that are naturally delivered to every site. We have designed our systems to harvest these resources where we can, to reduce our reliance on bulk supply and to reduce the waste that we send off-site for others to deal with.
As well as heating the houses, the sun heats most of our hot water through solar water heaters fitted to all houses and the common house. Combined with energy-efficient lighting and appliances, these measures considerably reduce our electricity needs.
Rainwater is collected from roofs into tanks and piped back for use within houses. All surface water and the overflow from the tanks flows into shallow vegetated channels beside the paths, which filter the water and encourage maximum soakage of stormwater into the ground. These channels flow overland down the middle of the site to discharge into a large pond at the northern end. The overland storm-water system has turned waste into a resource, reducing the impact on properties downstream, increasing biodiversity and becoming an asset to the neighbourhood.
We couldn't build everything we wanted in the construction phase. Though we intended to treat our own wastewater onsite and commissioned an initial design for this, political and regulatory constraints were against us. On-site electricity generation using photovoltaic panels was also considered, but proved too expensive when we also wanted to keep the houses affordable. In these and other cases, however, we've set aside land area or built in cables or pipes to facilitate these systems being added in the future. Earthsong will continue to evolve.
Recycling and Minimising Waste
All reusable materials from the two existing dwellings on the site were salvaged and reused, including the matai timber flooring and beautiful frosted glass 'tui' door reused in the common house, the rimu timber framing reused for furniture, and the old concrete cladding crushed and used for the driveway base.
Construction waste was greatly reduced over conventional construction as composite materials were largely avoided. Waste was separated at source and reused on site where possible e.g. timber offcuts, ramming earth, and plaster board (used on the garden to break down clay), or taken to the recycling station where possible. Waitakere City Council did a construction waste audit on Stage II(a) which found significantly less waste than for a standard housing project.
Residents' domestic refuse is also much reduced compared to the surrounding city norm. Organic kitchen and garden waste is processed on site using compost bins, worm farms, and the EM bokashi system, for returning to the organic vegetable gardens. A collection station near the entrance allows the sorting of metals, glass, plastics and paper for collection and recycling.