Best of the Best – Passive Butterfly

Armadale 2017

The driving force behind the ‘Passive Butterfly’ home was to create an exemplar for transforming heritage Australian homes into beautiful and super-efficient passive houses for the 21^st century, whilst retaining the heritage aspects of the building.

An unprecedented energy efficient and sustainable design approach refreshes this heritage home to holistically create joyful and beautiful spaces. The design optimises spatial efficiency, while maintaining a compact footprint, generates more energy than it requires, and re-uses collected rainwater for toilets and the productive garden. In order to create the northern aspect, the extension was conceived as a butterfly roof pavilion, cleverly linked to the old building. To optimise the spaces, the link between the existing heritage and new extension becomes the kitchen to remove hallways and minimise “circulation only” spaces.

Sustainable Strategy

• Holistic and innovative heritage renovation

• Targets Passive House standards

• Contextual site-specific response

• Optimised northern solar access for a south-facing extension – for winter and shade for summer

• Airtight vapour membranes throughout to improve performance and longevity

• In-depth research into Passive House principles and performance

• Lifespan of home improved

• High performance and super-efficient building envelope

• An exemplar, prototype and educational resource for future renovation projects

• Net-positive in energy

• 90% reduction in energy consumption

• Improved airtightness of building envelope – upgraded existing windows, roofs, walls and floors

• 74L/day/person of water usage

• Natural materials used with low embodied energy

• Passive design principles to improve performance and year-round comfort

• Optimised and efficient use of space – compact floor plan – existing floorplan improved and multi-use spaces introduced

• Edible food garden and composting

• Billabong and indigenous planting introduced

• Rainwater collection for garden and toilet flushing

Design Principles

• Solar Photovoltaic panels making the home net-positive in energy

• Energy efficient lighting (LEDs) and appliances

• No Gas (net positive CO2 performance)

• 10,000L of rainwater tanks used for flushing toilets and watering the edible productive garden

• Composting, native plants, billabong

• Water-efficient plumbing fixtures

• New and existing windows installed with triple glazed windows with low-e coating

• High density insulation in floors, walls (R5-6), ceilings and roofs (R7.0)

• Minimised thermal bridging

• Low embodied energy materials

• Airtight (1.2 Air changes per hour this compares with average Victorian home 18+ air change per hour) This provides better comfort and vastly improved health for the occupants – and eliminates potential major structural damage due to condensation.

• Heat recovery ventilation (HRV) saving 90%+ energy on ventilation

• Low VOC paints/sealer/varnish

• NatHERS 7.6 star rating + extra benefits of Passive House design approach lifting the performance and comfort well above 9 star

• Heat pump for high efficiency hot water and heating

• Thermal mass

• Hydronic floor heating

Design Principles

• Solar Photovoltaic panels making the home net-positive in energy

• Energy efficient lighting (LEDs) and appliances

• No Gas (net positive CO2 performance)

• 10,000L of rainwater tanks used for flushing toilets and watering the edible productive garden

• Composting, native plants, billabong

• Water-efficient plumbing fixtures

• New and existing windows installed with triple glazed windows with low-e coating

• High density insulation in floors, walls (R5-6), ceilings and roofs (R7.0)

• Minimised thermal bridging

• Low embodied energy materials

• Airtight (1.2 Air changes per hour this compares with average Victorian home 18+ air change per hour) This provides better comfort and vastly improved health for the occupants – and eliminates potential major structural damage due to condensation.

• Heat recovery ventilation (HRV) saving 90%+ energy on ventilation

• Low VOC paints/sealer/varnish

• NatHERS 7.6 star rating + extra benefits of Passive House design approach lifting the performance and comfort well above 9 star

• Heat pump for high efficiency hot water and heating

• Thermal mass

• Hydronic floor heating

Check out more about the project