Our cities are shaping the climate, so it’s time to rethink how we build them

As Earth Day approaches, climate discussions often turn toward energy systems, transport networks and global industry.

But one of the most influential climate systems is far less obvious.

It is the built environment that surrounds us - the homes we live in, the offices we work in, and the cities we are continuously expanding.

They all influence how much energy we consume, how much water we use, and how resilient our communities are to climate stress.

And in South Africa, their impact on emissions is significant.

Recent sector analysis shows that buildings account for roughly 23-24% of the country’s greenhouse gas emissions when both construction and operational energy use are considered. This includes electricity used for lighting, heating, cooling, appliances and building systems.

In other words, nearly a quarter of South Africa’s emissions are tied to the spaces we live and work in. That reality should guide how we think about development.

The problem is that buildings are life-long assets.

Once constructed, they often remain in use for decades. A commercial building developed today may still be operating in 2070 or beyond.

This means that design decisions made today can lock in emissions for generations.

The challenge is compounded by South Africa’s continued urban growth.

Cities such as Johannesburg, Cape Town, and Durban continue to expand as demand for housing, infrastructure, and commercial space rises. Research on the buildings and construction sector indicates that South Africa’s building stock could expand by 74% to 125% by 2050 as the country grows and urbanises. This rapid growth presents an opportunity to not only meet the demand for more space but also to ensure that affordable and dignified housing is integrated into these developments, creating resilient, sustainable communities for all.

Without changes to how buildings are designed and operated, this growth could significantly increase emissions.

Much of the impact comes from everyday operations. Electricity used for lighting, heating water, cooling buildings and powering appliances accounts for the majority of emissions associated with buildings. In a country where electricity generation still relies heavily on fossil fuels, inefficient buildings effectively embed carbon emissions into daily life.

The result is a substantial climate driver.

Cities are expanding to support economic development, yet the way we build them can unintentionally deepen environmental pressure.

Can policy help shape this development?

South Africa’s Climate Change Act, passed in 2024, establishes a framework for sector-specific emissions targets aligned with the country’s climate commitments. This legislation signals that industries (including the built environment) will increasingly be expected to contribute to national emissions reductions.

At the same time, market forces are reinforcing this transition.

Energy instability, rising electricity costs and water stress are forcing businesses and property owners to reconsider how buildings operate. Efficiency is evolving from an environmental goal into one that delivers financial and operational gains as well.

This is where the built environment becomes particularly important.

Buildings sit at the intersection of climate policy, infrastructure investment and urban development. The choices made by developers, architects, planners and investors today will shape not only the skyline of South African cities, but also their long-term environmental footprint.

And this is where the opportunity emerges.

Applying climate responsibility in healthcare infrastructure

While much of this shift is already taking shape in South Africa, similar approaches are emerging across the continent as cities respond to growing climate and infrastructure pressures. One example of this in practice is the African Medical Centre of Excellence (AMCE) in Abuja, Nigeria -  a landmark healthcare development designed to strengthen medical capacity across West Africa.

The tertiary-level multi-speciality facility includes a 170-bed specialist hospital, alongside research and education facilities, and forms the first of five centres planned across the continent. Backed by the African Export-Import Bank (Afreximbank) and developed in clinical partnership with King’s College Hospital NHS Foundation Trust, the project aims to serve more than 200,000 patients in Nigeria and 150,000 patients from neighbouring countries within its first five years. The hospital will ultimately expand to a 500-bed facility.

Ecolution Consulting was appointed as the LEED Independent Commissioning Agent, responsible for both Fundamental and Enhanced Commissioning of the building. Commissioning ensures that complex building systems (particularly energy and mechanical systems) operate as designed, improving efficiency, reducing waste and supporting long-term building performance.

Working closely with the design and facilities teams, Ecolution verified system performance, supported operational training, and developed system manuals to ensure the building’s energy systems operate in line with LEED commissioning standards.

Key sustainability features integrated into the project include:

• Optimised lighting controls

• Heat reclaim systems for efficient water heating

• High-efficiency equipment selection

• Advanced HVAC control strategies

Hospitals operate continuously and are among the most energy-intensive building types. Ensuring these systems perform efficiently is therefore critical for both operational resilience and environmental responsibility.

Projects like the African Medical Centre of Excellence demonstrate how sustainable building practices can support vital social infrastructure while improving energy performance and long-term building resilience.

A moment for reflection this Earth Day

Earth Day encourages us to reflect on the systems that shape our relationship with the planet.

Often, the focus falls on individual behaviour - how we travel, what we consume, or how we reduce waste.

But the built environment reminds us that the structures around us also shape our environmental impact.

Buildings influence energy use, urban heat, water consumption and long-term emissions.

In South Africa, where nearly a quarter of emissions are tied to buildings, the design of our cities becomes one of the most powerful tools we have for climate action.

So, the opportunity lies in recognising that every building designed today has the potential to contribute to a more resilient, efficient and climate-conscious future for South Africa’s cities.

This is equally true across the African continent, where rapid urbanisation is reshaping cities at an unprecedented pace. The decisions made today will not only define how African cities grow, but how they perform (environmentally, socially and economically) for generations to come.