KJ Tait

Reducing Carbon Emissions at 1-7 Harley Street, London



KJ Tait have completed a comprehensive assessment of whole life cycle carbon emissions for the redevelopment of 1-7 Harley Street in London. The evaluation covers all construction phases, from raw materials to disposal, highlighting opportunities to minimise environmental impact. 


Assessment Framework 


The assessment utilised RICS Whole Life Cycle Carbon methodology, breaking down the analysis into Modules A, B, C, and D.  The assessment examined embodied carbon at practical completion as well as carbon emissions throughout the building's lifetime. 


Key Findings 


Material Quantity Hotspots: Notably, concrete usage in the substructure emerged as a major contributor to carbon emissions. The requirement for a secant wall and piled foundations are the drivers for this. 


Enhancements for Sustainability: To reduce emissions, practical enhancements were explored: 

  • Adopting 60% GGBS concrete could reduce concrete-related carbon by 131kgCO2/m2. 
  • Increasing recycled steel content to 80% could result in a 22kgCO2/m2 reduction. 
  • Shifting to 100% recycled reinforcement may save an additional 3kgCO2/m2. 


Results and Impact 


The baseline specification indicated whole life cycle carbon emissions of 866kgCO2e/m2 over 60 years. By implementing the recommended enhancements and adopting sustainable practices, emissions could be reduced to 713kgCO2e/m2. These findings demonstrate the potential to significantly reduce the project's carbon footprint through well-considered material choices and practices.   




The 1-7 Harley Street case study exemplifies the importance of holistic carbon assessment in construction. By focusing on material optimisation and adopting sustainable approaches, the project showcased the potential for substantial reductions in carbon emissions.  We continue to work with the Stage 5 contractor to identify further means of reducing the embodied carbon of the development during construction.    


By integrating these measures, KJ Tait demonstrated how TotalEnergies House could achieve significant energy reduction, improve EPC ratings, and make strides toward a greener, cost-effective future.