Abbetthaus
Residential: Single Dwelling
Passivhaus Classic Certification
Scarborough, WA, 2023
This home in Scarborough presents a new vision of sustainable housing: one that balances affordability and efficiency, and is delight to inhabit all year round. Abbetthaus is the second certified Passive House in WA, and the first to demonstrate that PH certification can be achieved on a modest budget.
Located on a 213sqm laneway block, this house is the first iteration of an original concept developed by Leanhaus, which proves that green residential design can be both contemporary and attainable. The concept appeals to homeowners who might have previously believed that both architecture and advanced sustainability measures were beyond their budget and reach.
Our client’s vision aligned with the Leanhaus philosophy – which draws upon global best-practice in relation to building comfort and performance – and together we created a highly efficient, functional and liveable home.
The brief called for the home to be simple, affordable and robust. Taking cues from the site and orientation, and inspired by the desert Modernist style, the design features generous living spaces that open to the outdoors. The plan provides future flexibility, to accommodate a growing family or house-share scenario as needs change.
With high levels of insulation, air-tight construction and high performance windows, it is comfortable and healthy all year round.
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AIRTIGHTNESS n50 ACH@50pascals: .57
HEATING DEMAND (kWh/m².yr): 2.1
HEATING LOAD (W/m²): 14.5
PRIMARY ENERGY DEMAND (PE) (kWh/m².yr): 61.80
PRIMARY ENERGY RENEWABLE DEMAND (PER): 28.1 -
PROJECT NAME: Abbett Haus
LOCATION: Scarborough, Perth, Stirling, WA
NCC CLIMATE ZONE: 5 – Warm temperate
NATHERS CLIMATE ZONE: 52
YEAR OF COMPLETION: 2018
TREATED FLOOR AREA (PHPP sqm): 138.9
PROJECT TYPE: New Build
BUILDING TYPE: Residential: Single Dwelling
CONSTRUCTION TYPE: Timber Frame,
CERTIFICATION LEVEL/ ENERGY STANDARD: Passivhaus Classic
THIRD PARTY CERTIFICATIONS: Nathers -
MHRV SYSTEM: Zehnder Comfoair Q450
DOMESTIC HOT WATER SYSTEM: Steibel Eltron 300litre
EXTERIOR WALL TYPE, U-VALUE: Timber framed HD Glass Wool insulation, 0.3995
FLOOR SLAB TYPE, U-VALUE: In Situ Concrete, 5.833
ROOF INSULATION TYPE, MANUFACTURER: Bradford 240mm R6.0
ROOF CONSTRUCTION: Timber Frame
ROOF ENVELOPE U-VALUE: .198
GLAZING TYPE, U W-VAULE, G-VALUE, U G-VALUE: Double Glazed, .0.04, .3, 1.3
EXTERNAL DOOR TYPE, MANUFACTURER, U D-VALUE: uPVC, Rehau 2500 Series, 1.47
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The innovation in this project lies not so much in the selection of specifically sustainable products and materials, but rather, it is found in the application of fundamental design principles that underpin the project and the innovative assembly of those materials to achieve Passive House standards.
We started with first principles: passive solar design that maximises winter sun, and excludes summer sum, using expansive glazed openings to the north, and concrete floors for thermal mass. Overlaid upon these fundamentals are the Passive House requirements, including super insulation; air-tightness; and heat recovery and fresh, filtered air via a heat exchange.
The use of double-glazed windows – certainly atypical for Perth homes – is one of the more avant-garde aspects of this project. In contrast, the majority of the construction materials are off-the-shelf products that are readily available, although their detailing and application was atypical in a construction market that favours double brick walls and tiled roofs.
This was a deliberate strategy on the part of the architect, because it ensured that the budget remained reasonable, and also provided a realistic exemplar around how to easily incorporate high-level sustainability performance into regular suburban homes, rather than relying on exotic products with limited availability, or technological add-ons, which can of course be installed later if required.
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In contrast to typical Perth housing (built with double-brick skins), this house was constructed using renewable and recyclable timber. Our client initially didn’t consider Passive House standard as an attainable option, mainly because there was only one previous example completed in Perth, and it was a multi-million dollar house. Hence there was no established design or construction precedent for Passive House on a limited budget, and Perth is notorious for being a conservative residential construction market, with little appetite for innovation or risk. In addition, the small 15m x 14m block was overshadowed by a two-storey high wall on its northern boundary. which limited the potential for solar heat gain to our project in winter.
A key feature of Passive House is the high level of air tightness required. This was achieved through careful detailing, planning and sequencing of construction, to ensure that all junctions could be taped and sealed appropriately. As a result, all subsequent trades had to be carefully trained and overseen to ensure that the air-tight membrane wasn’t subjected to any unintentional perforations later in the build.
We also had to source affordable Passive House-certified floor-to-ceiling double-glazed uPVC windows and doors internationally, as these were not available in WA at the time. These were ultimately sourced and constructed in China using German-made Rehau window sections. This involved some level of risk, but resulted in high-performance and well-made glazing, which is integral to the natural light and thermal requirements of the design, and the ongoing sustainable performance of this house.
Project Members
ARCHITECT/ BUILDING DESIGNER: Ben Caine - Leanhaus
BUILDER: Chris Evans
PASSIVHAUS CERTIFIER/ CONSULTANT: Grün Consulting
INTERIOR DESIGNER: LAHAUS
STRUCTURAL ENGINEER: Total Structural Consulting
PROJECT MANAGER: Client
MECHANICAL ENGINEER: Fantech
ENVIRONMENTAL CONSULTANT: Certified Energy Assessments
WINDOW SUPPLIER: Rehau
HRV SUPPLIER: Fantech
INSULATION SUPPLIER: Bradford
BLOWER DOOR TESTER: Passive House Perth - Gillian Joyner
PHOTOGRAPHER: Jody D'arcy
AIRTIGHTNESS MEMBRANE SUPPLIER: Pro Clima
ROOFING SUPPLIER: Fielders