What type of EPCs are there and when are they used?

WHAT: Energy Performance Certificates for dwellings 
WHO: Produced by a Domestic Energy Assessor (DEA) 
HOW: A physical inspection of the property to collect the data 
WHEN: When dwellings are marketed for sale or to let. 
WHERE: Included in the Home Information Pack (sales) or as a standalone document (rentals)

WHAT: Predicted Energy Assessments 
WHO: Produced by a DEA from the design stage SAP rating 
HOW: A graph is created from the Energy rating and Environmental Impact rating generated from the SAP report provided to building control
WHEN: New build properties under construction and properties being converted or offered for sale off-plan 
WHERE: Included in the Home Information Pack

WHAT: On Construction EPC 
WHO: Produced by an accredited On Construction Energy Assessor 
HOW: From the properties plans and build specification 
WHEN: New build properties and converted properties, when complete. 
WHERE: In the Home Information Pack if for sale, or handed to the new owner if sold

WHAT: Energy Performance Certificates for non-dwellings (commercial property) 
WHO: Produced by an accredited Commercial Energy Assessor (CEA) 
WHEN: Non-dwellings when marketed for sale or to let 
HOW: Carrying out an inspection and collecting data 
WHERE: As a standalone document

WHAT: Display Energy Certificate 
WHO: Produced by an accredited DEC assessor 
WHEN: Created annually 
HOW: From charges for the services (gas, electricity etc.) into the building 
WHERE: As a standalone document to be displayed in a public building