ACE Research at the Association for Decentralised Energy (ADE) conducted a project for the Greater London Authority (GLA) to explore extending Minimum Energy Efficiency Standards (MEES) across all housing tenures in London. The research focused on policy drivers, barriers to retrofitting, and the environmental, economic, and social impacts of expanding MEES. The project supported London’s net-zero target by 2030 and involved gathering input from local authorities, social housing providers, and the retrofit supply chain through surveys.