Berowra Passivhaus
Residential: Single Dwelling
Passivhaus Plus Certification
Berowra Heights, NSW, 2024
The clients approached the designers wanting a healthy, comfortable, and efficient home that made the most of the site. It’s positioned on a ridge with expansive views across to the national parks that flank Berowra. The existing house was poorly built and badly sited, and made way for a home designed to suit the owners and their guests. The new residence makes the most of its location and creates satisfying connections to the natural surroundings.
Inside, the floor plan provides a snug for watching TV and a separate office with an L-shaped open plan kitchen/dining/living area. Tucked behind the kitchen is a hard-working space offering multiple functionalities. It houses the laundry, a kitchen pantry, utilities, and offers storage and a path to the back door. The two guest bedrooms are gathered to the south; Passivhaus standards of comfort mean these rooms will be just as warm and dry as the rest of the house.
-
AIRTIGHTNESS n50 ACH@50pascals: 0.23
HEATING DEMAND (kWh/m².yr): 14
COOLING DEMAND (kWh/m².yr): 9
HEATING LOAD (W/m²): 10
PRIMARY ENERGY RENEWABLE DEMAND (PER): 56
PRIMARY ENERGY RENEWABLE GENERATION (PER): 114 -
LOCATION: Berowra Heights, NSW
NCC CLIMATE ZONE: 5 - warm temperate
NATHERS CLIMATE ZONE: 56
YEAR OF COMPLETION: 2024
TREATED FLOOR AREA (PHPP sqm): 176
PROJECT TYPE: New Build
SECTOR: Residential: Single Dwelling
CONSTRUCTION TYPE: Timber Frame, Prefab
CERTIFICATION LEVEL/ ENERGY STANDARD: Passivhaus Plus -
MHRV SYSTEM: Zehnder ComfoAir Q350
DOMESTIC HOT WATER SYSTEM: Reclaim
EXTERIOR WALL TYPE, U-VALUE: Insulated 140mm timber framed wall, 0.279
FLOOR SLAB TYPE, U-VALUE: Insulated 190mm suspended timber floor, 0.288
ROOF INSULATION TYPE, MANUFACTURER: Bondor Solarspan
ROOF CONSTRUCTION: Structural insulated panel
ROOF ENVELOPE U-VALUE: 0.202
GLAZING TYPE, MANUFACTURER, U W-VALUE, G-VALUE, U G-VALUE: Double glazing, Logikhaus, 1.4, 0.35, 1.05 -
NUMBER OF MODULES: 50
HEIGHT, WIDTH OF ONE MODULE (m, m) : 1.7, 1.1
EFFICIENCY (%): 98
-
A striking curved timber T&G ceiling in the hallway and study is a masterclass in combining form and function.
The aesthetic is beautiful yet it also creates space for the ventilation ductwork which has to navigate the split skillion roof and the change in level at the front of the house.
Clerestory windows meet the curved ceiling, inviting in the winter sun.
-
The slope of the site was used to advantage, with an expansive workshop nestled below the house and behind the attached garage. The workshop and garage rest on a concrete foundation while the house stands on piers. A mostly covered deck on the north-east corner provides shelter and views and is slightly elevated above the gardens the owners are taking delight in establishing. There is provision to store 30,000L of rainwater.
The use of prefabricated wall and floor panels from Carbonlite offered multiple benefits: faster on-site construction and lower embodied carbon. Envirotecture has worked with this supplier before and this experience ensures an efficient process. The roof is a SIP panel from Bondor, which likewise delivered construction efficiencies. The exterior is clad in Weathertex, an Australian hardwood product which has excellent properties with regard to sustainability and durability, and recycled hardwood timber.
Project Members
PASSIVHAUS CERTIFIER: Detail Green
ARCHITECT /PASSIVHAUS CONSULTANT/ MECHANICAL ENGINEER: Envirotecture
BUILDER: Red Cedar Constructions
STRUCTURAL ENGINEER: Tall Ideas
WINDOW SUPPLIER: Logikhaus
HRV SUPPLIER: Fantech
AIRTIGHTNESS MEMBRANE SUPPLIER: ProClima
BLOWER DOOR TESTER: Blower Door Services
PHOTOGRAPHER: Jonathan Cohen