How do you turn a south facing extension into a passive house? Respectfully placed behind the existing heritage home to the north the solution was a sculptural butterfly roof soaring northwards. Highlight windows wash the living room rammed earth wall, a heat sink on cold winters days. Attention to detail has been of premium importance on this project as the client is targetting Passivhaus standards of airtightness and thermal integrity. There must be no chinks in the armour!
This project includes:
– internal rammed earth thermal mass wall
– PV panels
– heat recovery system
– super insulation, including upgrade to the existing building
– stringent attention to preventing thermal bridging.
Type: Residential alteration & addition
Size: Site 435m2, Existing building 150m2, Proposed building 170m2 & shed 25m2, Garden/Outdoor Entertaining 241m2
Challenges: south facing block, heritage overlay, bulky adjoing properties, sloping block, targetting Passivhaus standard
Building Star Rating: TBC
Features: 3 bed, 2 bath, open plan living, lounge/home office, two courtyards for outdoor living, rammed earth wall, morphed butterfly roof
Hot water: sanden energy efficient hot water heat pump
Water Saving: 2 x 5,000 L underground water tanks, grey water divesion to garden
Renewable Energy: Solar PV system
Passive Design: Morphed butterfly roof provides high-level shaded north facing windows to bring light into south facing extension, minimised east/west glazing, airlock between existing and proposed, operable windows located for cross ventilation, high thermal mass in rammed earth and living slab, high level airtightness
Building materials: Rammed earth, Australian hardwood timber cladding stained, high levels of insulation to proposed and existing, steel framing minimised
Windows: Timber high performace double glazed windows
Active Heating & Cooling: MHRV (Mechanical Heat-Recovery Ventilation), Haiku Ceiling fans, Morso woodheater, hydronic towel rails
Lighting: Daylight maximised , LED fittings
Paints, finishes & floor coverings: Tectinic floor boards, low VOC paint throughout, external blinds shade doors & windows where necessary
Other ESD features: building footprint minimised to preserve garden for growing food
This is how we solved the challenge of a outh facing block with an existing northern heritage home.
Demolition has been completed on our latest sustainable renovation
Check out our feature story in the Fifth Estate. In Luke’s interview with Willow Aliento he discusses his approach to intelligent sustainable design.