Launched at COP29 under the Subnational Climate Action Leadership Exchange Partnership, the Zero Emission and Resilient Buildings (ZERB) Accelerator brings national and subnational governments together to rapidly decarbonize and climate-proof the buildings and construction sector. Implemented by C40 Cities, World Resources Institute (WRI) and the Under2 Coalition (Climate Group), and funded by Bloomberg Philanthropies, the Accelerator supports governments in designing, implementing and enforcing policies that reduce building emissions and increase resilience to climate change impacts.

The ZERB Accelerator has since become a recognized global initiative and an active member of UNEP's Global Alliance for Buildings and Construction (GlobalABC). Through its newly created Expert Advisory Group (EAG), it convenes over 40 organizations working across areas such as green finance, building codes, capacity strengthening and national-local coordination.

In its first year, the ZERB Accelerator piloted ambitious multilevel climate action with national and subnational partners in Colombia, Kenya and the Philippines. It helped advance mandatory building standards and national roadmaps while strengthening enforcement capacity across subnational governments, ultimately contributing to national and international climate mitigation goals. These achievements were presented by government partners from Colombia and Kenya at a panel event during COP30 to showcase how multilevel government partnerships can help unlock impact across the buildings and construction sector.

Panelists speaking at a climate-friendly buildings event at the UN climate summit.
Panelists at the ZERB Accelerator panel event at COP30 shared experiences on how multilevel action can accelerate the transition to zero emission and resilient buildings in Colombia and Kenya. From left to right: Champa Pantel (Executive Director for Governments and Policy, Climate Group), Carolina Stibel Duarte (Climate Change Director, Ministry of Environment, Colombia), Kennedy Matheka (Deputy Director of Buildings Safety and Climate Resilience, Ministry of Lands, Public Works & Urban Development, Kenya). Photo by Toby Walker/Under2 Climate Group

Colombia

In Colombia, the ZERB Accelerator is supporting local implementation of the country's new mandatory building energy and water regulation (Resolution 0194). It is working in partnership with the Ministry of the Environment and Sustainable Development (MESD); the Ministry of Housing, City and Territory (MHCT); and subnational governments of different sizes, including Bogotá, Santiago de Cali, Valledupar and Maicao.

In 2025, WRI led ZERB Accelerator activities with the Ministry of Housing and local EAG partners — including the Colombian Council of Sustainable Construction (CCCS) and the Swiss Agency for Development and Cooperation's CEELA project on building efficiency implemented by EBP Chile — co-hosting a series of webinars and working sessions for subnational governments. These sessions aimed to disseminate information about Resolution 0194 and co-design implementation guidelines, as well as enforcement and reporting mechanisms, suitable for nationwide adoption by municipalities of all sizes. The ZERB Accelerator and EAG partners then used insights from these sessions and international best practices to create recommendations for the enforcement of the Resolution and the design of the digital platform that will be used as its monitoring and control mechanism. The platform is meant to help maximize adoption by subnational governments as well as representatives from the construction sector.

Lastly, in coordination with the Coalition for High-Ambition Multilevel Partnerships (CHAMP) initiative, the project supported the update of Colombia's NDC 3.0 for the housing sector. The new NDC recognizes sustainable construction as a key measure to help reach the national target of reducing greenhouse gas emissions 51% by 2030, relative to the emissions projected for that year under the reference scenario. Resolution 0194 is consolidated as one of the main instruments to operationalize this commitment.

People attending an event.
The event "Weaving a Climate-Resilient Future for NDC 3.0 from the Housing, Water and Sanitation Sector," held on September 3, 2025, and organized by WRI, MESD and MHCT.

Kenya

In Kenya, the ZERB Accelerator has partnered at the national level with the State Department of Public Works (which sits under the Ministry of Lands, Public Works & Urban Development) and at the subnational level with the Council of Governors and the pilot county of Kisumu. This collaboration, led by WRI with the instrumental support of the Kenya Green Building Society (KGBS), aims to ensure that local governments are included in developing and implementing two key national frameworks: the National Decarbonization Roadmap for Buildings and Construction (2026-2040), which is led by the Global Building Performance Network (GBPN); and the National Green Building Standards, which are coordinated by the International Finance Corporation (IFC) Africa. The ZERB Accelerator also provided recommendations for the design, implementation and enforcement of these new standards.

On Oct. 27-28, 2025, the ZERB Accelerator hosted a two-day workshop in Naivasha, Kenya, bringing together governments, EAG partners and local actors to gather feedback on the Decarbonization Roadmap and discuss key elements for local implementation of the Green Building Standards. Additionally, through a series of working meetings, participants reviewed past and current experiences with green buildings and building regulations to identify gaps, challenges and opportunities for Kenya's new standards.

Insights and data from local government representatives, together with technical guidance from the World Bank and the American Society for Heating, Refrigeration and Air Conditioning Engineers (ASHRAE), are now informing the design and implementation of the National Roadmap and National Green Building Standards, particularly in shaping how Kenya's county governments can take effective local action. 

The Philippines

The Philippines is a relatively new addition to the ZERB accelerator; Quezon City and the national Department of Energy joined in the last quarter of 2025. Led by C40, the multilevel partnership and the EAG established a two-year workplan that will set out a process for revising national codes to improve the performance of new buildings. The new codes are meant to incorporate best practices in building energy efficiency and low carbon and resilient design. A range of local expert stakeholders will be included in the working groups.

The Road Ahead

The ZERB Accelerator and partners are entering a transition in 2026 as the initiative's first stage comes to a close. The Accelerator's work moving forward will align with the CHAMP initiative to strengthen national commitments supported by local action. EAG members and partner governments will continue to guide and support individual country workplans.

In Colombia, CCCS and CEELA will continue supporting local capacity building and digitalization of the monitoring system. In Kenya, IFC Africa will continue developing the National Green Building Standards, while KGBS and GlobalABC engage in capacity building with Kisumu and other county governments to pilot local implementation. In the Philippines, C40 will continue to support ZERB Accelerator activities in 2026 to deliver the workplan agreed with the jurisdictions and EAG partners, contributing to national and international commitments.

The ZERB Accelerator stands as an example of the powerful impact that is possible through multilevel partnerships. Looking ahead to 2026 and beyond, stakeholders will continue to seek new partnerships and resources that are essential for sustaining progress toward a resilient, zero-emission buildings sector.