Detached Residential Dwelling – 79 Kitchener Rd, Melville
The clients for this project wanted one thing from the outset. This was to be their dream home to retire into and it had to fit their brief. A brief that collided Californian Case Study bungalow with its sleek lines, low slung roofs and floor to ceiling glazing; with a modern eclecticism of recycled materials, textures and industrial chic.
The site is a rear lot in a battle axe subdivision which was also completed by Arklen.
The house is compact at 160m2 but has been designed to cater for optimal site orientation and function. The brief called for 2x bedrooms with an additional guest bedroom for visitors to be used infrequently, but whom could stay for considerable periods of time. It also required a music studio where the clients can run their music lessons from home, but without the strain of having students come through the main house to sit and wait for their lessons; and most importantly the main requirement was a large living space where they can entertain, cook and party with the footy on.
The response is a clever pinwheel plan, with all of the living and sleeping areas opening onto a central north facing courtyard with a small concrete pool. The main bedroom wing flanks the courtyard to the east with full height high performance glazing providing uninterrupted views of the garden whilst capturing the westerly sea breeze. The living area is a large 6x10m long room oriented to the north with floor to ceiling 4m wide glass sliding doors to bring the courtyard right into the house. This is the heart of the house, and a large deck extends the full length of the living area out to meet the pool.
The guest bedroom is detached from the main house and sits opposite the main bedroom wing on the west with a large span cantilevered roof connecting it back to the living area, which creates a sheltered alfresco BBQ area out on the deck.
The plan is about careful consideration of function and orientation to ensure breezes are captured, the sun is kept out in summer but welcomed deep into the house in winter and to ensure all living spaces are bathed in northern light.
Floors are polished concrete and the western and northern walls are reverse brick veneer construction to take advantage of thermal mass, whilst the remainder of the house is heavily insulated timber framed wall and roof with aluminum framed high performance glazed doors and windows. The clean sleek lines and finishes are offset with the internal finishes including recycled bricks set into the polished concrete slab, recycled timber cladding, industrial light pendants and cabinetwork constructed from black faced form ply.
- Client: Jeff Cahill and Jackie Burdett
- Architect: Wilt Design – Will Thomson
- Builder: Arklen
Results Summary
A Life Cycle Assessment has been carried out on the proposed design calculating the greenhouse gas emissions over the whole life of the project as per EN 15978 scope and system boundary. The benchmark chosen to compare against is the International Residential Benchmark Weighted (x10 Dwellings). The results are summarised below:
Project features
It is observed through the LCA modeling that the following areas have the greatest impact to the overall environmental footprint of the building:
Design Life
High quality design differentiates this project from surrounding residences and extends the lifespan to 80 years by reducing redevelopment pressure in the near future. Higher design life means that all initial impacts are diluted over a longer period of time therefore improving the performance on a per year basis.
Materials Selection
A careful selection of materials guaranteed higher durability, lower embodied impacts and lower maintenance requirements. The materials list included:
- Polished concrete floors;
- Concrete replacement – 50% fly-ash blend;
- Timber cladding internal finishes;
- Light construction in timber frame for walls and roof.
An increase in overall embodied carbon was mainly because of a large 5 kW solar PV system. It’s estimated the system will get replaced three times over the life of the building. However, the substantially reduced “Operational Impact” due to the renewable energy input offsets this increased “Embodied Impact” many times over during its design life. The main advantage of a solar system is that it offsets carbon intensive grid electricity.
Net Positive Operational Carbon
The project was designed for reduced energy demand and included:
- Ceiling fans to reduce demand from split system;
- High efficiency LED lighting;
- Motion and lux sensors for outdoor lighting;
- Induction cooktop;
- Well ventilated fridge space;
- Electric heat pump hot water system;
- Energy monitoring;
- Solar pool heating;
- High efficiency pool water pumping and filtration;
- 5kw Solar PV System.
Water efficiency features include low flow shower heads (5.5L/minute) and grey water diverters to garden helped reduce annual water consumption as well as greenhouse gas emissions associated with mains water supply and treatment.
After all energy efficiency measures were implemented, a large solar PV system of 5kW was installed. The system will produce excess clean electricity which will generate carbon credits to offset impacts associate with materials and recurring impacts, resulting in a whole of building whole of life performance of 1,086 kgCO2e/occupant/year, or a 74% savings in equivalent carbon emissions when compared to a residential benchmark.
This assessment was conducted by Fei Ngeow and certified by Rich Haynes from eTool in May 2015.