In 2019, the Green Building Council South Africa (GBCSA) awarded its first 4-Star Green Star Sustainable Precincts certification in Africa

Words Nicole Cameron IMAGES Garden Cities

Green, greener, greenest

Sunningdale, Cape Town
Green Star rating:
4 Star Green Star – Sustainable Precincts Pilot V1.1 (2019)
Type of buildings:
Residential homes
Date certified:
16 January 2019
Project Size:
566 100m²

Comprising 429 homes, Northridge Coastal Estate (NCE) was designed to preserve biodiversity and enhance community interaction, promoting an active and sustainable lifestyle among residents. The project was planned by historic Cape Town development company Garden Cities, as a further phase of its flagship Cape West Coast suburb, Sunningdale. Having been featured in + Impact magazine in the past, in this issue, we revisit this innovative development for a progress update…

The estate has been designed to preserve biodiversity, with a conservation area created to protect the dune thicket vegetation.

“Regrettably, Covid-19 and its ripple effects resulted in a delay in the Northridge Coastal Estate project kicking off, with the first housing scheme commencing only in May 2022,” says Renier Smith, Group Manager: Engineering and Planning, Garden Cities NPC. “As of November 2023, we had delivered the first 92 houses – now occupied – together with the community & education facility [clubhouse], the administration building, conservation area [dune thicket with boardwalk] and various landscaped open-space areas,” he says. “In terms of the Green Star rating and the credits targeted, we have achieved some very easily, while others are posing more of a challenge. We have credits in hand across various spheres spanning governance, liveability, economic prosperity, environment and innovation.” Smith says that the Sustainable Precincts Rating (SUP) tool) has provided upfront, clear guidance as to how to achieve these goals.

A community garden allows residents to consume their own produce.

The sustainable building features on the project include more than 30% of the annual energy need being met through on-site power generation systems, LED infrastructure lighting and external lighting with an upward light output ratio of less than 5%. In terms of water savings, there are rainwater harvesting tanks, and non-potable water is used for irrigation. The downstream stormwater retention facilities achieve a 1-in-2 year Average Recurrence Interval (ARI) event discharge (being able to handle big storm events occurring on average every two years). Through roofing and vegetation that has a solar reflectance index (SRI) of less than 35, there is a reduction of the heat island effect. Heat islands are urbanised areas that experience higher temperatures than outlying areas, as structures such as buildings, roads and other infrastructure absorb and re-emit the sun’s heat more than natural landscapes such as forests and water bodies.

Northridge Coastal Estate became Africa’s first 4-Star Green Star sustainable precinct in 2019.
Footpaths and cycling facilities enable residents to walk and ride around the estate.

NCE boasts open green spaces with a conservation area of approximately seven hectares, leading to the site’s enhanced ecological value. Footpaths and cycling facilities enable residents to walk and ride around the estate, with amenities such as food and retail services available within a walkable distance. A rich community life is cultivated through a community centre and food garden, together with a dog park and sports facility.

The Sustainable Precincts Rating (SUP) tool has provided upfront, clear guidance as to how to achieve the project’s goals.

A dedicated effort

“The challenges on the Green Star process were limited, with perhaps only the Climate Adaption Plan (CAP) posing some difficulty, owing to the fact that a CAP was something new in the context and size of what was encapsulated in the NCE precinct,” Smith says. “Some of the risks had to be revisited, assessed and included into the design responses, which will be submitted as part of the recertification process.”

A rich community life is cultivated through a community centre and food garden.

Smith says some other minor challenges were overcome in the following areas:
• Recycling: Privatising the recycling of 429 units was problematic from a financial and sustainability perspective, but through successful engagement with the City of Cape Town, NCE was included within the municipality’s recycling scheme.
• Water sources: While alternative water resources were targeted as part of the project’s sustainability approach, with very saline groundwater resources and limited access to treated effluent supply resources (and not wanting to place an added burden on potable water supply), Garden Cities undertook bulk-treated effluent supply projects to unlock treated effluent water supply sources with the support of the City of Cape Town, to ensure and facilitate sustainable supply to this end.
• Environmental management: This part of the process included educating and training sub-contractors and the complete supply chain, in order to align and utilise the newly created Environmental Management Plan.
• Safe Places credit: This credit is a new target, where Garden Cities has incorporated “designing out crime principles”, which includes various security solutions, interventions, technologies and an all-encompassing app to manage and engage with residents.

“The process of achieving and maintaining a Green Star Sustainable Precinct is administratively intense, and requires a great deal of effort and patience on the side of all parties involved,” says Smith. “Of course, it is absolutely worth it, but it is important to be aware of the level of dedication and commitment required.”

The estate’s clubhouse provides a community and educational facility.
Residents are encouraged to get to know their neighbours and spend time living together in community.

Looking ahead, NCE has some exciting sustainability initiatives in the pipeline, involving further development and implementation of technology-driven tools and the use of IoT (Internet of Things), which lends itself to various community-aligned type projects. “These engagements and processes will incorporate residents and will be kept simple and straightforward, so that they are well received by the local community and not seen as burdensome in any way,” says Smith.

Through roofing and vegetation that has a solar reflectance index (SRI) of less than 35, there is a reduction in the heat island effect.

“The innovation category is the credit likely to be further considered and developed to achieve accreditation, but it is a fine balance to achieve between benefits added and the costs associated, so as to not create a long-term burden on residents’ operational levies.”

Of the 429 planned residential units, 92 have been built and are occupied.

Resin8 is one of the innovative processes that NCE has undertaken in pursuing the Green Star Sustainable Precinct rating, which has now been incorporated into standard development and roll-out. Resin8 technology takes all seven types of plastic waste and turns it into a lightweight aggregate that adds strength, reduces weight and increases thermal properties. The Resin8 technology was utilised in the clubhouse parking bay kerbs. Another innovation has been the construction of the conservation area’s boardwalk, which is built from a sustainable wood composite decking product, made from 95% recycled and reclaimed materials.

The boardwalk is built from a sustainable wood composite decking product, made from 95% recycled and reclaimed materials.

Bold leadership in sustainability

Fabio Venturi, founder of Terramanzi Group, the sustainable design consultants who achieved this ground-breaking certification for the project in 2019, and who are progressing with the recertification process, attributes what has been accomplished to dedicated teamwork and collaboration. “With pressing global climate change and resource challenges, there has never been a more appropriate time for bold leadership in the property sector to create a meaningful and measured difference on this planet for now and for generations to come. We applaud Garden Cities for their radical goals, which they have been able to formalise and implement with focus and drive.”

Further recognition for the project was achieved in June 2023 when Garden Cities won in the Sustainable City Initiative category at the Big 5 Southern Africa Construction Awards. NCE was applauded for having been designed to incorporate all the essentials of sustainable development, from preserving the local biodiversity and conserving energy, water and materials to planning for climate change, espousing smart city features and enhancing community interaction.

There has never been a more appropriate time for bold leadership in the property sector to create a meaningful difference.

“As we’ve progressed along this journey, we’ve incorporated a number of mindset changes. This has resulted in an overall greener approach with less wastage, and better techniques considered. The team has been instrumental in the success of this project – especially Danielle Cronje, who has played a pivotal role in ensuring the wonderful achievements at NCE,” says Smith. Given that the journey is far from over, it seems that when it comes to this West Coast sustainable precinct, the best is yet to come!