A few green buildings don’t make a sustainable city

by Ofentse Sefolo
A few green buildings don’t make a sustainable city

Over the past decade, sustainability has grown rapidly in the built environment, with every second supplier, manufacturer and designer claiming “green”, and buildings proudly flaunting the stars that have been awarded for achieving the criteria set out by the Green Building Council of South Africa.

In fact, building green has practically become the new normal in the local commercial market, due to the continuous pressure placed on the construction industry to address inadequate energy resources, carbon reduction targets and building energy efficiency standards for the country.

However, Alison Groves, regional director for building services at WSP, makes a good point: “While the design concepts, innovations and building methods that make a building green may be used on a number of built projects within a certain radius or precinct, a collection of green buildings is not enough to make up a green town or green city.”

She explains that a town or city has layers of impact that extend far beyond the boundaries of individual buildings.

Think wider
On a micro-economic scale, some of the primary considerations should include the following:
• Atmosphere – air quality, ozone depletion and urban heat island effect.
• Built environment – buildings, public spaces, amenities and services.
• Urban infrastructure – particularly access to transport, water, waste, energy and food.
• Natural attributes – land, water, air quality and/or contamination.
• Social impacts –ICT, connectivity, sense of space and community, etc.

“With this in mind, we also have to realise that the urban form will not rapidly and materially transform itself towards more efficient and compact towns or cities, as a green city is a complex undertaking for any economy – whether developed or emerging,” Groves adds.

Building future cities
Traditionally, the various disciplines involved in the urban design process – from civil to electrical engineering, architecture, environmental consulting, traffic engineering and town planning – have always acted independently of one another.

However, Groves points out that in the development of a sustainable city one needs not only to break down the barriers of isolation between these disciplines, but must also incorporate transport engineering, future energy, climate change strategy, water, waste management and socio-ecological systems into the preliminary planning stages.

Currently, the constraints of inadequate infrastructure are adding to the complexity of developing greener cities, and in order for the country to move forward, new infrastructure models have to be put in place that involve both the private and public sector.

“For infrastructure to be truly sustainable, it needs to take into account the future potential demands of the whole precinct, and enable the integration of services and systems through the use of shared services and utilities, as well as be financially and technically flexible for servicing energy, water and waste/materials requirements of the city,” Groves highlights.

What about existing buildings?
New buildings and precincts aren’t the only opportunity for going green though. Groves points out that vacancy rates for commercial office space is currently in excess of 15,9% (higher than the national average) in urban hubs that are economically key, such as Sandton, which probably means that the demand for new buildings will slow somewhat in the short to medium term.

“This leads me to believe that there is an excess of available office space and as a result, there likely won’t be many new buildings being built in the short to medium term,” she states.

This should be seen as an opportunity for urban regeneration through refurbishing and retrofitting, rather than a limitation.

Groves highlights two main drivers for urban regeneration:

#1: Building for resilience
“We can no longer afford to take a passive approach to adaptation and planning needed to mitigate the adverse effects of climate change,” she notes. “The built environment’s contribution to global carbon emissions continues to rise by about 1% a year and coupled with challenges around aging infrastructure and insufficient energy and water resources, urban regeneration is a necessity.

“This urban renewal can take place in different forms, but the most important consideration is to incorporate climate-responsive design into maintenance and refurbishments, being mindful of resource constraints and future weather assaults which may impact the comfort and safety of old buildings.”

#2: Optimising building performance (and commercial viability)
Some cynics might argue that refurbishments are difficult, and do not make economic sense. However, there is a strong business case for implementing green building interventions, according to Groves.

“For example, if specified and installed correctly, systems and structures can produce a sustainable return on investment (ROI) that may amount to between 20% and 70% of energy and gain revenue through this investment. Demonstrating these improvements would be a real incentive to attract tenants to older buildings in the more established part of the city.”

In addition, businesses and their people are becoming increasingly socially conscious to the effects of climate change. These users also recognise the role green buildings can play in managing critical resources more sustainably.

Evaluate the full lifecycle
For an objective and balanced view, the full lifecycle costs of any intervention should be evaluated. This can be done by conducting a full audit of the building performance using a Green Star rating tool such as the Existing Building Performance tool.

The Green Star new build rating tool can also be used to rate substantial redevelopment projects, where plant and facade are overhauled. Doing so provides a solid metric to measure the success of the interventions and justify the capital investment.

Green building interventions
While the specifics will vary from building to building, Groves prescribes that green building interventions should, at the very least, include:
• The materials used, and specifically the recycled/reused contents.
• Achieving improved energy efficiency, especially through the use of natural light balanced with efficient light fittings and smart switching.
• Improving water consumption with more efficient fittings.
• Optimising temperature and air flow management, through considerations around the facade, placement of people and driving efficiencies through upgrades to the mechanical plant (HVAC) system.
• Onsite recycling access and waste-to-landfill considerations.
• Operational measures to guide building managers and occupants to adopt more sustainable processes.
• A good understanding of the local context.

Always wear your sustainability glasses
“Sustainability is a lens through which the planning, project delivery and development processes focus to achieve the needs of the communities today without sacrificing the capacity for future generations,” Groves states. “Urbanisation, demographic shift, environmental changes and new technologies are reshaping the way city leaders are looking at sustainability. Resilience and liveability must be the desired outcomes of planning and design processes – and, ultimately the goal should be that we are building liveable spaces that are people-centric, integrated, connected, smart, nimble and resilient – where societies can thrive, well into the future.”

Full thanks and acknowledgement are given to Alison Groves, regional director for building services at WSP, for the insights shared.

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