Torrens Passive House

Description: Passive House Premium
Building Type: Kindergarten | Day Care
Location: Torrens, ACT 2607
Number of Apartments/Units: 1
Treated Floor Area According to PHPP: 486sqm
Construction Type: Timber construction
Year of Construction: 2018

Description

Torrens Early Learning Centre is a daycare and kindergarten facility in Canberra ACT and is the only privately-owned Passivhaus educational facility in the world. The client’s goal was to build the healthiest and most sustainable childcare centre in Australia and meeting the Certified Passivhaus standard was a key performance requirement. 

The centre caters for up to 90 children plus around 20 staff. It consists of two two-story buildings linked by a large external deck and playground. The first was an adaptation of an existing building’s footprint and while it aimed for Passivhaus certification, it did not meet the final airtight criteria. The second building houses six large classrooms and met the Passivhaus Premium standard. 

More information is available on the property here.

Project Members

Architecture: Christie Hartfiel Architectural Design / Can PLAY / VRD Design
Building services: Rudds Consulting Engineers
Building physics: H3 Space
Certifier: Detail Green
Craftsperson / parties involved: Carbon Lite / Phil Bates Building Services / Can PLAY

Special Features

Windows were carefully designed to distribute natural light into the classrooms while also shielding unwanted heat gain in summer. The mechanical ventilation system was proven during bushfires in January 2020, when Canberra had the dubious distinction of the worst air quality in the world. (Air quality index readings above 200 are considered hazardous; readings in Canberra peaked at 7700.)

The Design/Build Process

The client offered some advice for those considering commercial Passivhaus projects. Firstly, employ main trades and sub-contractors who are certified Passivhaus tradespeople or at least trained in the methodology. Second, while there may be a cost premium compared to a Code-minimum build, low operating costs mean a quick return on investment. 

“As a commercial building, it is world-class in its thermal efficiency, and therefore highly energy efficient. My other buildings cost me $15,000 a year in electricity, while Torrens costs only $36. And that is mostly the grid-connection fees!”

—Torrens Early Learning Centre Owner. 

Technical Details

• Exterior wall: CARBONlite's PANELlite system, certified Passive House component.

• Cladding: vented cavity - breathable membrane - 18mm OSB - 140mm mineral wool insulation (0.035 W/m.K)- air tight membrane - 45mm services cavity - 10mm plasterboard

• U-value: 0.263 W/(m2K)

• Basement Floor / Floor Slab= PANELlite concrete slab floor system
  100mm concrete slab on ground - 50mm PIR foam (0.02W/m.K)- 22mm particleboard flooring.

• U-Value: 0.469 W/(m2K)

• Roof: PANELlite roof system, Metal deck roof - vented cavity - breathable membrane - 18mm OSB - 240mm mineral wool (0.043W/m.K)- 45mm services cavity - 12mm acoustic insulation - 10mm plasterboard

• U-Value: 0.177 W/(m2K)
  Frame: Neuffer, Eco Plano Angular

• Timber: aluminium frames

• U w-value: 0.91 W/(m2K)

• Glazing: Triple Glazing

• U g-value: 0.52 W/(m2K)

• G -value: 58 %

• Entrance door: Neuffer Glazed entry doors

• U d-value: 1.03 W/(m2K)

Mechanical systems

• Ventilation: Systemair, Save VTC 700
  3 x ventilation units to service whole building

• Heating Installation: Recirculating type heating and cooling via multi head reverse cycle split systems. One indoor unit per room.

• Domestic Hot Water: Electric heat pump

Additional information

• Ecological Aspects: Large 29KWp solar PV array on building roof

• Construction Costs: 2030 €/m2 Treated Floor Area according to PHPP (Costs of group 200-700)

• Building Structure Costs (gross): 1910 €/m2 Treated Floor Area according to PHPP (Costs of group 300-400)

PHPP values

• Air Tightness: n50 = 0.6/h

• Annual Heating Demand: 15 kWh /(m2a ) calculated according to PHPP

• Heating Load: 12 W/m2

• PE demand (Non-Renewable Primary Energy): 64 kWh /(m2a ) on heating installation, domestic hot water, household electricity and auxiliary electricity calculated according to PHPP

• PER demand (Renewable Primary Energy): 29 kWh /(m2a ) on heating installation, domestic hot water, household electricity and auxiliary electricity calculated according to PHPP

• Generation of Renewable Energy: 143 kWh /(m2a ) based on the projected area
  Cooling Load: 1 W/m2
  Cooling and Dehumidification Demand: 4 kWh /(m2a ) calculated according to PHPP