BRE Quarterly Update
5 Jun 2008
Briefing Energy performance certificates for non-domestic buildings will provide proof to clients that designers have achieved the following client brief: reduction of operational energy demand of buildings to meet corporate social responsibility and sustainability policy objectives
The Energy Performance of Buildings Directive states that by January 2009 all countries within the European Union has to put in place systems to allow assessors to undertake Energy Performance Certificates for all buildings, both domestic and non-domestic, when either constructed, rented or sold. The approach has been implemented as part of a European drive toward reducing the energy consumed in buildings.
For new build, the technical standards set by Scottish Building Standards Agency (SBSA) has been the conduit for delivery of the EPC produced when buildings warrants are applied for Section 6: Energy at design stage with the EPC produced at construction warrant application. The ‘Approved Certifiers of Design Scheme’ run by BRE allows designers to certify their own designs, allowing for a reduction in the building warrant application fee and more importantly to avoid bottlenecks during the warrant application process.
For existing buildings, there are two types of certificates for non-domestic buildings; the Energy Performance Certificate (EPC) that measures the intrinsic energy performance of the building based on its design, and Display Energy Certificate (DEC) that measures how the building actually performs. EPCs must be produced when the building is leased, at lease renewal or sold and is valid for a period of 10 years from date produced. The DEC is renewed on an annual basis and must be displayed in public buildings with a useable floor area of greater than 1000m2.
The implementation of the EPC for non-domestic buildings will be delivered differently in the regions of the United Kingdom. In Scotland EPC assessors must sign up to an organisation operating under a Protocol signed with SBSA. The protocol for Scotland is that all buildings over 1000 m2 must be compliant by January 2009. However in England and Wales, a stepped implementation has been introduced where all buildings over 10,000 m2 must be assessed by April 2008, buildings over 2,500 by July 2008 and all other buildings over 1000 m2 by October 2008. At the time this was written Northern Ireland had yet to publicly introduce their implementation plan.
The certificates will rate the energy efficiency of the buildings on a scale of A (very efficient) to G – a system already familiar as it is the approach used on white goods.
The aim is to differentiate good from poor performers and help investors, buyers and tenants to decide which building they should occupy or purchase. Over time, better performers should attract a premium thereby increasing the business case for energy efficient buildings. The EPC will also carry recommendations on how the buildings’ energy can be improved.
The EPC for non-domestic buildings is produced using the Simplified Energy Building Model (SBEM) using approved interfaces such as the default iSBEM or an increasing range of commercial products. SBEM allows for the objective comparison of buildings on a consistent basis using a standard calculation method. Buildings that are too complex to be accurately rated with a standardised calculation will instead be rated using commercially available dynamic simulation tools.
The rating process, whether using SBEM or a simulation tool, calculates the demands for heat, ventilation, cooling, lighting and hot water, based on geometry, construction and standard activity schedules for the building. It then calculates the energy needed to meet the demands using system types, efficiencies and control corrections.
Display Energy Certificates provide details of in-use performance that are compared to established benchmarks together with recommendations on how energy efficiency can be improved. The methodology for calculating these operational ratings is still being finalised. In broad terms they will be derived from the energy consumption of the buildings per square metre floor area, determined from meter readings and from measurement or agreed drawings of the property.
Qualified assessors will be needed to meet the requirement for EPCs in the commercial and public building sector. The application process to deliver under the Protocol of an organisation such as BRE in Scotland or become accredited for England and Wales is dependent on qualifications and experience. BRE Global (formerly BRE Certification) will provide fully auditable accreditation of trained and qualified assessors in the delivery of EPCs and DECs to the marketplace. Full details of training courses can be found by contacting BRE direct using the contact details below.
BRE is currently working with a wide range of property portfolio owners who have already recognised the potential impact of EPCs; whether that is to the property value, for tax planning purposes or impact on their Corporate Social Responsibility reporting statements. Attitudes are changing corporately and will no doubt affect the design specifications of buildings procured as clients become more informed. Tools such as BREEAM allow design professionals to demonstrate their ability to design to meet higher energy standards, however for contractors, in particular for DECs, the certification process will provide a post construction review to determine energy performance of non-domestic buildings. Therefore certificates will provide proof for the client that the design relative to energy performance of the buildings has been achieved. It is also anticipated that organisations will volunteer to display the DEC as a public presentation of their commitment to energy reduction.
For more information and/or training on EPC/DEC please contact Laura Birrell at BRE Scotland.