These documents have been produced by DCHI to provide clarity to the process of deciding when and how the Energy Performance of Buildings (Certificates and Inspections) (England and Wales) Regulations 2007 apply. It is anticipated that there will be a series of documents produced to assist property professionals and others affected by the regulations with understanding their obligations. The initial documents cover Commercial Energy Performance Certificates and Display Energy Certificates. DCHI Guidance When a Commercial Energy Performance Certificate (EPC) is required Current version 1.6 Release date 30/10/2009 When a Display Energy Certificate (DEC) is required Current version 1.2 Release date 20/8/2009