Designing and delivering commercial buildings that are all-electric, highly sustainable and powered by renewable energy is both possible, and commercially astute, as Salta Properties has demonstrated at Nexus Corporate Business Park in Mulgrave. Designed by Gray Puksand architects and constructed by Hickory, the 631 Springvale Road project also tackled another milestone for both the developer and the local industry, with the first Fitwel rating for a multi-tenant base building in Australia.

As the development’s sustainability consultants, Cundall provided the support and guidance to achieve 1 Star Fitwel along with a 5 Star Green Star Design and As-Built V1.2 Certified rating. The development also targeted 4.5 Star NABERS.

 

De-risking all-electric

As the all-electric approach was new to Salta, extensive investigations were first undertaken into the business case compared to a conventional electric building services plus gas for heating, on-site cooking and hot water.

Salta engaged the project Independent Commissioning Agent, Building-Performance, to prepare a report considering whole of life factors and gain a well-rounded analysis of the possible energy sources, including natural gas and electricity market trends, greenhouse gas implications, and several financial analysis methods.  The report demonstrated the benefits of 100% electricity outweighed electricity plus gas and provided the project team with confidence that this was the right direction for the project.

In addition, the elimination of gas combined with installation of on-site renewables provides greater long-term operational cost certainty and eliminates risks including gas price volatility, emissions-related rate levies and long-term maintainability of gas-reliant plant and equipment. The asset was therefore designed to operate on 100% electrical energy, comprising both on-site renewables from an 96kW solar PV array and the balance through grid-supplied electricity.

 

Holistic approach to energy performance

The all-electric approach also involves considering the demand side of the equation, as energy-efficiency is crucial to a successful electrification approach. Energy efficiency features include passive design optimisation for natural daylighting; smart lighting controls system; and a BMS system with real-time energy data and analytics for performance monitoring and exception reporting.

To reduce the risks of a performance gap between detailed design stage thermal modelling and the completed asset, air tightness testing was undertaken at practical completion to verify the quality of the building envelope.

 

Climate adaptation planning

Climate adaptation plans are also becoming part of standard practice for Salta. For this site, risks include storm events and extreme heat. The masterplan for Nexus has embedded greening and open space as part of a precinct-wide strategy for encouraging human health and wellbeing in addition to reducing the urban heat island effect.

At the building level, urban greening for 631 Springvale Road includes a level 1 Terrace, façade greening and a landscaped public plaza. This also further contributes to reduced energy use by providing local microclimate cooling which means a lowering of HVAC energy demand. There is also a rooftop multipurpose sports court which in conjunction with rooftop solar PV reduces thermal gain via the roof.

 

The application of Fitwel requirements

The value of holistic thinking about the synergies between masterplan, building architecture and the operational phase is evident. Features such as the urban greening and rooftop sports court contribute to multiple aspects of sustainability, including the requirements for Fitwel.

Some of the Fitwel-specific aspects include additional architectural and fitout features that emphasise and encourage physical activity and wellbeing, such as car-free pedestrian linkages to the business park walking trail and permanent outdoor fitness gym; and an additional entrance for 631 Springvale Road that is oriented to connect to pedestrian routes and outdoor shared amenity areas such as the public landscaped plaza featuring a BBQ area.

Within the building, a wayfinding and navigation strategy incentivises and rewards stair use, guides building occupants to amenities and enhances the attractiveness and functionality of health and wellbeing features including the active travel facilities and lactation room. The stair design incorporates bright colours, upgraded lighting and motivational messages, making it a more enjoyable choice to use the stairs in preference to lifts.

 

Future-proofing

The focus of design, delivery and operational decisions for 631 Springvale Road has been overtly tenant-centric, with an emphasis on occupant wellbeing, ongoing low operational costs for energy and a low occupant emissions footprint.

Thinking around the emerging trends for decarbonising transport was also embedded into design and delivery. Future-ready elements include pre-installed EV charging infrastructure for 15% of car parking spaces comprising 20 chargers already installed and charging infrastructure including isolator switches installed for a further 100 chargers in future. The extensive low-carbon mobility infrastructure includes 96 bicycle parking spaces and a bike repair station. The active travel provisions are also a component of the 1 Star Fitwel strategy developed by Cundall.

Rainwater is harvested and stored in an 84kL tank and reticulated for amenities flushing and irrigation of landscaping. As part of the 5 Star Green Star strategy, Green Cleaning and Green Operational Guidelines support waste to landfill reduction and minimise the use of toxic chemicals within the indoor environment. The materiality, fitout and finishes all specified low- or no-VOC materials, with EPD documentation obtained for all products to verify suitability.

By exceeding minimum compliance with the National Construction Code across key performance benchmarks including Section J Energy Efficiency and passive thermal comfort, the development is also future-proofed for changes to codes and standards as the wider market shifts towards net zero.

Another dimension of long-term thinking was designing for change and adaptability, to minimise the churn of embodied carbon and resources as tenant needs change. All the floor plates at 631 Springvale Road were designed and constructed for separability into up to four separate tenancies, including a building services design that delivers four tenant electrical distribution boards and associated metering, four water and sewer connection points, and separate HVAC zoning.

The central core is also configured so that four separate tenancy entries can be constructed.  This means Salta can be completely flexible in the leasing offers with small, medium and large floor plate configurations being available without requiring any services or structure reworking.  Should a single tenant lease an entire floor, the split services strategy remains in place to allow future provision for splitting floors at the end of the lease to meet market requirements.

 

Social value in practice

In another departure from conventional thinking, the business park is located in the outer suburbs of Melbourne, where PCA A-Grade properties are not standard practice. To date, Salta has now delivered seven Green Star rated commercial buildings in the Nexus Corporate Business Park.

As the Covid pandemic taught us, people value working close to where they live. In this ‘flight to quality’ market, the availability of wellbeing-focused office space in the heartland of family-friendly residential suburbs can give employers an edge in enticing people to come and work in an office.

There’s a flow on benefit also from the social value perspective, as local employment supports residential property values, helps ensure a flow of students for local schools and underpins the viability of local retail and hospitality.

Where often the concepts of net zero asset operations, electrification, social value, wellbeing features and climate adaptation are discussed and delivered in a siloed manner, this project has shown that doing all the things, all at once, might look like a bold and difficult stretch goal initially, however the enhanced capabilities and experience obtained make transformative practice attainable as a new business-as-usual approach.

 

Authors:

Amy Banks, Senior Sustainability Consultant, Cundall

Nikki Paton, Head of ESG at Salta Properties