The Ministry of Housing, Communities and Local Government (MHCLG) has published guidance on the Energy Calculation as a Service (ECaaS).
ECaaS is a calculator service run by MHCLG that provides a performant implementation of the Home Energy Model (HEM), a methodology for predicting the energy performance of buildings, for various future statutory purposes including, but not limited to, calculating compliance with the Future Homes Standard (FHS).
The service will become the only valid means to confirm compliance with Part L of the Building Regulations when referring to the Future Homes Standard. For other users, the underlying software libraries are open source and can be used to conduct calculations for non-statutory purposes.
More information can be found here.
