Building green for a sustainable planet

This World Environment Day, we are highlighting the importance of the green, affordable housing in reshaping the housing landscape and its role in minimising environmental impact. The buildings and construction sector is a major contributor to global greenhouse gas (GHG) emissions contributing to approximately 37% of global emissions.  

UN-Habitat states that by 2050, 68% of the world’s population is projected to live in cities, driving the need for at least 40 million new homes, especially in sub-Saharan Africa and parts of Asia. With the increasing demand for housing, the importance of building green is crucial for promoting socially and environmentally sustainable cities, and communities. This is vital for protecting the environment, preserving biodiversity, and addressing the climate crisis.  This presents an opportunity to rethink and reimagine the built environment sector prioritising sustainability, affordability and community well-being.  

 At Reall, climate action is embedded at the core of our work. We are committed to addressing the climate crisis through mitigation, adaptation, and resilience by integrating climate-smart solutions across all our initiatives. Through this approach, we aim to drive innovation, close critical data gaps, champion affordable housing that is resilient to changing climate, and support sustainable urban development.  

To help reduce environmental impacts, the built environment sector can consider adopting the following strategies. Examples from Reall are included where appropriate to illustrate these approaches.

Low carbon materials and processes 

The 2024–2025 Global Status Report for Buildings and Construction highlights that embodied carbon from materials such as steel and cement contributes significantly to emissions, accounting for 18% of global CO₂ emissions related to buildings. The sector is currently not on track to achieve net-zero carbon and climate resilience targets by 2050, as progress is slow and fragmented. The report emphasises the urgent need to increase the use of low-carbon materials and to promote circular construction practices, among other measures which this blog will consider, alongside nature-based solutions.  

Reall, Linkbuild, and Base Bahay Foundation collaborated to deliver a housing project in Daraga, Albay, Philippines. This project utilised Base Bahay’s innovative cement-bamboo frame technology, a sustainable construction method that combines bamboo’s strength and flexibility with cement-based composites. The technique provides an affordable, eco-friendly solution that is also disaster resilient. 

Reall demonstrates its commitment to green, affordable housing by adopting and promoting the EDGE green building standards across its projects. This commitment has led to significant milestones, including the support of the delivery of the first EDGE-certified homes in Tamale, Ghana, and the first EDGE Advanced-certified homes in Pakistan. 

Circular economy practices

Building Materials and the Climate: Constructing a New Future highlights the role of circular economy practices in reducing the environmental impact of the construction sector. It outlines three key strategies that need work together to decarbonise building materials: avoiding unnecessary extraction and production, shifting to regenerative and low-impact materials, and improving the decarbonisation of traditional materials like steel and cement.  

A Reall supported housing project in Karachi, Pakistan, uses ModulusTech’s modular construction model to reduce carbon in the built environment. The approach is based on the Intermesh System, which applies circular economy principles. Homes are prefabricated off-site, flat-packed for easy transport, and assembled quickly on-site. This method reduces construction waste and supports material reuse. It also achieves up to a 90% reduction in embodied carbon compared to traditional building techniques. The result is durable, affordable housing for low-income communities and a scalable model for low-carbon development. 

Nature-based solutions (NbS)  

Integrating nature-based solutions into the built environment play a vital role in enhancing climate resilience, supporting biodiversity, and improving human well-being. Features like green roofs, urban forests, wastewater treatment systems, and green spaces help manage stormwater, reduce the urban heat island effect, and offer natural flood protection.  

Reall has funded an ECOSTP (Ecological Sewage Treatment Process) plant for a rental housing project in Bengaluru, India, developed by its partner Janaadhar. This innovative system uses biomimicry to treat wastewater. The plant is designed to operate efficiently within the housing development, providing an environmentally friendly solution that reduces water pollution. By integrating nature-based solutions into affordable housing, the project illustrates how sustainable infrastructure can address the needs of communities while protecting the environment. 

Green and sustainable buildings provide numerous environmental and social benefits that significantly impact our lives. Some of these benefits include reducing reliance on energy-intensive cooling systems, lowering greenhouse gas emissions, enhancing indoor air quality, and supporting mental well-being. 

Green construction doesn’t always mean higher costs. With thoughtful design, the use of locally available materials (low-carbon/bio-based), and careful planning, green affordable housing can be both practical and cost-effective. This makes it increasingly possible to build in ways that are environmentally friendly. 

At Reall, we are committed to demonstrating, evidencing and advocating for green, affordable housing by embracing environmentally friendly construction practices. In doing so, we can help reduce environmental impacts while also supporting community well-being and encouraging the growth of resilient, sustainable communities.

Written by Jayamali Kankanige, Climate and Green Buildings Co-ordinator and edited by Clare Ollerenshaw, Programme Lead – Climate Advocacy and Green Buildings