One cubic metre of concrete has a carbon footprint of 350Kg CO2e, making this staple material in the construction industry one of the biggest contributors to greenhouse gases in the world. Hybrid cements can be used in applications to fully or partially replace cement with important environmental, technical and importantly cost benefits - including 80 - 90% reduction in CO2 emissions and improved resistance to fire and aggressive chemicals.

The standard Portland cement replacement by SCM's(Supplementary Cementitious Materials) like hybrid cement, is approximately 15 - 30% worldwide. Due to early strength requirements for buildings, SCM's generally only constitute 15 - 20% of the binding content of concrete.

Leading up to the 2010 FIFA World Cup, which South Africa was the host nation, the government led 'Gautrain' infrastructure project, a high speed commuter train project was built in the province of Gauteng The project used a total of 344000t (tonnes) of cement, 210000t was Ordinary Portland Cement and the remaining 134000t was Hybrid Cement. The replacement with hybrid cement offset carbon emissions which would have require a living rain forest for forty year, spanning 2.0 x 3.5Km to sequestrate.

In October of 2018 the S.A. Department of Public Works, the custodian of all immovable assets vested in the national government, launched its Green Building Policy through which it will mitigate carbon emissions and adapt the sector to a green built environment. The Green Building Policy is also a demonstration of South Africa's support to ongoing local and international commitments like the Green Economy Accord, the National Water Act, and National Environmental Management: Waste Act.

The use of hybrid cement as partial replacement in the 'Gautrain' project and the release of the Green Building Policy, demonstrates that the South African government has no reason for not adopting legal framework that necessitates the use of hybrid cement for all built related work in the country, ensuring emissions reduction targets are reached. Policy reforms must take into consideration and expropriate all possibilities to ensure that South Africa peaks, plateau's and reduces greenhouse gas emissions.

By necessitating the partial replacement of Portland cement with hybrid cement in all construction work in the built environment, 15 - 30% of carbon emissions can be removed from all construction work in the built environment. We see from the Gautrain project that a reduction of 44.3% in carbon emissions from built environment construction projects is possible.