Sustainable House Day, Christie Walk 6, Adelaide, SA

Christie Walk, initiated by non-profit environment group Urban Ecology Australia Inc (UEA), is an exemplary ecological development in the CBD of Adelaide, South Australia. The project places community and ecology side by side in its ideals for achieving a healthier society and environment. It has involved community and client participation in its design and development.
The inner-city location is an important part of the ethos of UEA: that rather than turn our backs on the urban environment and sprawl across the rural land we need to transform the city into a healthier place that is more self-sufficient, energy-efficient, resource-conserving, productive and respectful of the living world. The concept was primarily the ‘brainchild’ of architect Paul Downton and Urban Ecologist Chérie Hoyle.

Climate: Mediterranean as in Adelaide CBD

Design process
-    Building of Christie Walk started in 2000, with 16 Considine Place being the second dwelling finished in Christie Walk as a row of 4 townhouses
-    Stages 1 & 2 comprise 4 townhouses, 4 strawbale cottages and 6 apartments. Stage 3 consists of 13 apartments and community facilities (meeting hall,  kitchen, reading room/library, disabled toilet, laundry.)
-    Original owner moved in December 2001 and a new owner moved in September 2006

Site and landscaping
-    3-level townhouse facing north
-    Balconies on the first and second floors and a sunspace in the ground floor
-    Solar efficiency depends on vegetation so original owner planted 2 grape vines and neighbour planted a glory vine which is directed over our 2 adjoining townhouses
-    Vines were planted in mid 2002 and by summer 2003/4 were up to the top balcony and provided shade to the front (north facing) side of the house.
-    2 native hibiscus were planted at the front of the house in mid 2002 and they also provide shade.
-    A raised garden bed and brick paving are on the south side of the house.

Materials
-    All materials are chosen for non-toxicity - in this house use of polyvinyl chloride (PVC) and formaldehyde has been avoided wherever possible
-    Corrugated Colorbond steel roof
-    Autoclaved aerated concrete (AAC) blocks for all walls, except party walls for which poured earth was used for the first 3 metres (poured earth proved to be very expensive and gave an unsatisfactory finish, so party walls were completed using AAC blocks)
-    Floor in ground floor area is laminated bamboo, other floors are pinus t&g floorboards overlaid with Marmoleum. Bathroom floors are tiled.
-    Recycled wood (typically Oregon) used for door frames, skirting boards, kitchen cupboards and all timber trim.
-    Cupboard shelves, built-in cupboards, doors built in Ecopanel, a strawboard product which does not contain woodchips or toxic glues.
-    Kitchen bench tops in Abet Laminati a laminate produced very efficiently with minimal off-gassing and glued on ‘Ecopanel’ straw fibre boards with non-formadehyde glues.
-    Interior paints and varnishes from Bio Paints chosen for best environmental and health performance.
-    All windows and doors are double-glazed (except for the venting louvre windows)
-    Spiral staircase of recycled timber on steel frame.

Heating and cooling
-    North facing aspect, thick concrete slab, airflow design, high levels of insulation (R3+ to the roof, R3 to the walls), shared separating walls and double-glazing make for a very efficient solar house
-    Drapes used in the lounge area, and blinds and heavy curtains in the bedrooms
-    Two wall mounted low wattage Eco-Panel heaters (425w) are used occasionally in winter
-     small electric fan heater is used occasionally in winter in the bathroom prior to baby’s bathtime
-    Portable evaporative cooler used on top floor on very hot summer nights
-    Foam and rubber draught excluders are used on all external doors and windows to minimise draughts
-    Fans on each level used to circulate air in summer
-    In summer, bamboo blinds on outside of first floor windows are used on the hottest days
-    Flyscreens have been fitted to most doors (security screens on ground floor) to enable cross flow of air on summer evenings.
-    Ventable skylight at the top of the staircase, which acts as a thermal flue, is closed in winter and opened in summer to evacuate hot air.

Lighting
-     All lights are compact fluorescent. Most globes are now at least three years old (being nearly present in the house when the new owners arrived in September 2006).
    

Water
-    House is connected to stormwater collected and then recycled from two 20,000 litre underground tanks and used for toilets and garden watering throughout the development.
-    Showers have restricted flow shower heads
-    A drinking water filter has been installed under the sink
-    Solar hot water provided by 2 collectors

Appliances
-    All new appliances have been chosen for their efficiency
-    No washing machine needed due to provision of shared laundry facility
-    Small under-counter fridge and freezer pigeon pair are used
-    Gas cook top is the only gas appliance

Behaviours
-    Small footprint of house (and corresponding small size of roof) means that solar electricity installers assessed the house as unsuitable for installation of solar panels. Have purchased green energy as an alternative
-    Solar hot water electric boost backup used overnight occasionally (eg 5 times p.a.) in winter after several cloudy days in a row
-    Council kerbside composting and recycling facilities are always used along with communal collection of other plastics for recycling
-    Car is owned but central location of the residence and use of bikes when possible minimise car usage to approx 5,000 km p.a.

Performance
-    Winter quarter electricity 239.4 kWh plus Winter off-peak usage 122.7 kWh) ($101)
-    Summer quarter 284 kWh. ($102). Over this period there were 2 people in residence
-    Electricity accounts include contribution to Green energy