The Passivhaus Trust has published guidance endorsing EnergyPlus, the open source building energy simulation engine maintained by the US Department of Energy, as a viable tool for UK domestic retrofit assessments. The guidance, developed alongside architects Architype and Levitt Bernstein, argues that EnergyPlus offers greater transparency than proprietary SAP software. It follows criticism of Standard Assessment Procedure's accuracy in low-energy retrofit scenarios.

Source: RIBAJ