A short note on Energy Performance Certificates

EPCs are a legal requirement when any commercial building over 50m² is built, sold or let.

An EPC sets out the energy efficiency grade of a commercial building by rating it from A (most efficient) to G. This is based on the performance potential of the building itself (i.e. the fabric) and the services (i.e. HVAC and lighting).


There are three levels of buildings under the EPC requirements which relate to the complexity of the
building and will affect the type of EPC assessor needed.

Level 3: simple buildings similar to domestic premises in terms of fabric and services. These buildings can be assessed using the Simplified Building Energy Model (SBEM) software.
Level 4: larger, more complex buildings with fabric and services installations that are not found in domestic buildings.
Level 5: complex buildings, featuring advanced energy saving technologies (e.g. Daylight dimming controls, night cooling, etc) and require the use of Dynamic Simulation Modelling software.

Austin has the in-house capacity of creating and lodging EPCs for building of all levels, as it employs a registered CIBSE Low Carbon Energy Assessor for levels 3, 4 and 5.


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