The retrofit of ‘70s office buildings curtain walls in London

Abstract

The built environment accounts for 44% of UK emissions, of which 18% are from non-domestic buildings. Considering that a façade's performance accounts for more than 50% of the energy consumption of a building, the retrofit of a ‘70s curtain wall system is analysed along with common issues such as poor insulation, fire risk, air infiltration and absence of natural ventilation, all of which are known to affect both occupants’ comfort and energy demand negatively. The methodology includes thermal and energy analysis of the Euston tower, results from which are used to inform an analytical model representing a more extensive building stock. Orientation, occupation, window to wall ratio and floor heights are examined as the main factors influencing heat gains, and different passive design solutions are tested to reduce them. Combining these passive design strategies shows a reduction of cooling demand by up to 91% and overheating hours down to 0% from base case to best case, demonstrating how the retrofit of curtain walls in office buildings is essential to cut emissions, reducing energy demand and improving comfort and productivity.