A Profitable Sustainable ecoHome
The Sunbury ecohome was designed for a developer and his family. The house reduced their energy consumption by two-thirds and sold for twice the construction costs.
The ecohome was designed to be a resource efficient, low allergy home for a developer and his family. The house site was located on top of Sunbury Hill in a windy and exposed location. 5 years after construction, the ecohome was sold for a twice as much as the cost of construction.
A Brief Description
The ecohome was designed to be a passive solar home. This included the principles of passive solar heating and solar cooling. Utility rooms and bedrooms were zoned to the cooler south side of the house. Living areas were located on the warmer north side of the ecohome. Window placement throughout the ecohome was considered for cross ventilation and exhausting of hot air of the house.
The low-tech and commonsense approach to passive solar design of the ecohome made it easy for the occupants to understand exactly how the building systems worked in a passive solar home. It is a logical approach to designing a home to suit the climate and to optimize the benefits of passive solar heating and cooling.
Detailed Feature Description
Designed for minimal energy consumption, the ecohome features a covered solar court, with openable sky windows, and a garden courtyard.
Plants in the garden courtyard allow hot northerly summer breezes to be cooled via plant transpiration before entering and cooling the ecohome.
Cross ventilation and nightime exhausting of hot air allow for passive solar cooling of the ecohome. High windows and raked ceilings allow for the exhausting of hot air during summer.
A solar pergola, eaves and sun shading devices protect the north facing windows of the solar court from excessive heating during summer.
Passive solar heating during winter months keeps these areas of the home warm. A tiled concrete slab provides thermal mass to absorb passive solar heating. Air transfer ducts move warmed air from the north side of the house to the cooler south facing bedrooms. Windows placed on the north side allows the winter sun into the house whilst shading prevents the summer sun.
“As the ecohome seemed so spacious, the client had difficulty believing the small floor area”.
Strategic window placement allow for long distance vistas of the surrounding rolling hills from the back of the house. This, and the high ceilings in the living areas, provides a sense of spaciousness in a home with a small footprint.
The Weather Conditions
The ecohome is located on Sunbury Hill in a windy exposed site facing west. It was the first house built in this green field development for solar designed housing estate.
The location is in a temperate dry climate zone, with cooling summer breezes from the south and blustery cold south-westerly winds in winter.
The front of the house faces west and the living areas are orientated to the north. The ecohome features an airlock entry at the front of the house. The client appreciated this entry room as it provided good protection from the strong westerly winds of this exposed house site.
Living in the ecohome, the family found that their energy consumption was reduced to one-third of another Sunbury House where they had previously lived.
The household water consumption was reduced to one half of the Melbourne average for a family of this size.
Flexibility in the zoning of the ecohome, Sunbury included the glass wall of solar court can be opened to closed.
The passive solar design of the ecohome included the following features:
- Living areas orientated towards the north, including solar court
- Utility areas and bedrooms on the cooler south side of house
- Multi-use of areas
Flexibility was designed into the ecohome so that internal rooms could be opened up and increased in volume during summer and closed down to reduce room area requiring warming in winter. High ceilings in part of the house facilitated exhausting hot air in summer. Ceiling fans moved this warmed air downwards when needed in winter.
The house eaves and solar pergola shade the north side of the house. Solar film has been placed on the west facing windows.
Positioning the garage and the garden court on the north east side of the ecohome provides shade the early morning summer sun.
The house has High efficiency double glazed windows throughout. There are high levels of ceiling and wall insulation.
Cross ventilation was considered when positioning windows. Rooms were designed to have an unobstructed flow of air throughout the ecohome.
The ecohome is located close to the former Sunbury Asylum which opened in 1879. This heritage building and complex was later turned into one of Victoria University Campuses and closed in 2008. It has since been opened for ghost tours. The Sunbury Asylum is a Victorian architectural style of an eclectic mix of elements.
The ecohome makes reference to the heritage building with the roof forms on the street facade. These roof forms also facilitate the exhausting of hot air from the roof spaces with ventilated shafts of the solar chimneys.
The passive solar design principles of the ecohome established the rectilinear form of the building. With a mezzanine office built into the main roof form, the roof terrace sits between the front two roofs at the front of the house. The stone clad plinth of the ecohome protects the lower levels of the external walls. Window sizing and placement were considered with orientation and cross ventilation in mind.
House Size: 230 m2
- Airlock entry
- Solar Court
- Garden Court
- Photovoltaic power supply grid connected
- Solar Hot water
- Rainwater tank
- Grey water tank
- North orientation
- Passive solar design
- Tiled concrete floor
- Sun shading and solar pergola
- Cross ventilation
- Secure night time exhausting of hot air
- Thermal mass
- Acratex cladding
- High performance double glazed windows and doors
- Designed for flexible zoning
- Heat recovery in ventilation system
- Low chemical content building materials
- Minimal construction waste and reuse of site materials
YourHome – Australian Government Publication
The ecohome, Sunbury was one of the feature homes in the Australian Government’s Your Home DVD – An interactive step-by-step guide to comfortable stylish and healthy living.
The ecohome, Sunbury was case study in the Australian Governments YourHome CD and technical reference YourHome.
MBA Master Builders Association National Environment and Energy Building Efficiency Award for Housing – Under $300,000.
The Architecture Show Magazine and the Francis Greenway Society Green Buildings Awards – Silver Medal.