Energy Performance Certificate
Encyclopedia
Home information pack
Under Part 5 of the Housing Act 2004 a Home Information Pack , sometimes called a Seller's Pack, was to be provided before a property in England and Wales could be put on the open market for sale with vacant possession. There is separate legislation for Scotland that requires anyone selling a...
s (HIPs) for domestic properties with four or more bedrooms . When the requirement for HIPs was removed in May 2010, the requirement for EPCs continued. The scheme for HIPs was extended to encompass three bedroom homes from 10 September 2007. Rental properties, which have a certificate valid for 10 years, required on a new tenancy commencing on or after 1 October 2008. They are a result of European Union Directive 2002/91/EC
Directive on the energy performance of buildings
The Directive on the energy performance of buildings is the Directive 2002/91/EC of the European Parliament and Council on energy efficiency of buildings. The Directive came into force on 4 January 2003 and had to be implemented by the EU Member States at the latest on 4 January 2006...
relating to the energy performance of buildings, as transposed into British law
Transposition (law)
The incorporation of international law is the process by international agreements become part of the municipal law of a sovereign state. A country incorporates a treaty by passing domestic legislation that gives effect to the treaty in the national legal system....
by the Housing Act 2004
Housing Act 2004
The Housing Act 2004 is an Act of the Parliament of the United Kingdom. It introduces Home Information Packs, which came into force for homes of four or more bedrooms on 1 August 2007. It also significantly extends the regulation of houses in multiple occupation by requiring HMOs to be licensed...
and The Energy Performance of Buildings (Certificates and Inspections) (England and Wales) Regulations 2007.
However, EPCs have been criticized by many professional bodies for their inaccuracy, and low reliability for old and listed buildings.
Procedure
The energy survey needed to produce an EPC is performed by an assessor who visits the property, examines key items such as loftLoft
A loft can be an upper story or attic in a building, directly under the roof. Alternatively, a loft apartment refers to large adaptable open space, often converted for residential use from some other use, often light industrial...
insulation
Building insulation
building insulation refers broadly to any object in a building used as insulation for any purpose. While the majority of insulation in buildings is for thermal purposes, the term also applies to acoustic insulation, fire insulation, and impact insulation...
, domestic boiler
Boiler
A boiler is a closed vessel in which water or other fluid is heated. The heated or vaporized fluid exits the boiler for use in various processes or heating applications.-Materials:...
, hot water tank, radiator
Radiator
Radiators are heat exchangers used to transfer thermal energy from one medium to another for the purpose of cooling and heating. The majority of radiators are constructed to function in automobiles, buildings, and electronics...
s, window
Window
A window is a transparent or translucent opening in a wall or door that allows the passage of light and, if not closed or sealed, air and sound. Windows are usually glazed or covered in some other transparent or translucent material like float glass. Windows are held in place by frames, which...
s for double glazing, and so on. He or she then inputs the observations into a software programme
Computer program
A computer program is a sequence of instructions written to perform a specified task with a computer. A computer requires programs to function, typically executing the program's instructions in a central processor. The program has an executable form that the computer can use directly to execute...
which actually performs the calculation of energy efficiency
Efficient energy use
Efficient energy use, sometimes simply called energy efficiency, is the goal of efforts to reduce the amount of energy required to provide products and services. For example, insulating a home allows a building to use less heating and cooling energy to achieve and maintain a comfortable temperature...
. The programme gives a single number for the rating of energy efficiency, and a recommended value of the potential for improvement. There are similar figures for environmental impact
Environmental degradation
Environmental degradation is the deterioration of the environment through depletion of resources such as air, water and soil; the destruction of ecosystems and the extinction of wildlife...
. A table of estimated energy bills per annum (and the potential for improvement) is also presented, but without any reference to householder bills. The householder will have to pay for the survey, which costs around £90 for a four bedroom house. The exercise is entirely non-invasive, so assessors have to take certain amount of information on trust from householders, such as whether or not cavity wall insulation is present unless there is evidence such as drill holes present.
Domestic EPCs
The calculation of the energy ratings on the Energy Performance Certificate (EPC) are based on the RDSAPv3 procedure, which is a simplified version of the SAP2005. SAP is short for Standard Assessment Procedure and RDSAP for Reduced Data SAP; both are derived from the UK Building Research EstablishmentBuilding Research Establishment
The Building Research Establishment is a former UK government establishment that carries out research, consultancy and testing for the construction and built environment sectors in the United Kingdom...
's Domestic Energy Model (BREDEM), which was originally developed in the 1980s and also underlies the NHER
National Home Energy Rating
The National Home Energy Rating Scheme is both a UK accreditation scheme for energy assessors and a rating scale for the energy efficiency of housing.The NHER is owned and operated by National Energy Services...
Rating. EPCs have to be produced by Domestic Energy Assessors who are registered under an approved certification scheme.
Property Details
The certificate contains the following property details:- Property address
- Property type (for example detached house)
- Date of inspection
- Certificate Date and serial number
- Total floor area
The total floor area is the area contained within the external walls of the property. The figure includes internal walls, stairwells and the like, but excludes garages, porches, areas less than 1.5 m high, balconies and any similar area that is not an internal part of the dwelling.
The A to G Scale
Energy Performance Certificates present the energy efficiency of dwellings on a scale of A to G. The most efficient homes – which should have the lowest fuel bills – are in band A. The certificate uses the same scale to define the impact a home has on the environment. Better-rated homes should have less impact through carbon dioxide (CO2) emissions. The average property in the UK is in band D or E for both ratings.EPC Recommendations
The certificate includes recommendations on ways to improve the home’s energy efficiency to save money. The accuracy of the recommendations will depend on the inspection standards applied by the inspector, which may be variable. Inspectors, who may be Home Inspectors (HIs) or Domestic Energy Assessors (DEAs), are audited by their accreditation bodies in order to maintain standards. The recommendations appear general in tone, but are in fact bespoke to the property in question. The logic by which the RDSAP program makes its recommendations was developed as part of a project to create the RDSAP methodology, which took place during the early years of the 21st century. The EU directive requires the EPC recommendations to be cost effective in improving the energy efficiencyEfficient energy use
Efficient energy use, sometimes simply called energy efficiency, is the goal of efforts to reduce the amount of energy required to provide products and services. For example, insulating a home allows a building to use less heating and cooling energy to achieve and maintain a comfortable temperature...
of the home, but in addition to presenting the most cost effective options, more expensive options which are less cost effective are also presented. To distinguish them from the more cost effective measures, these are shown in a section described as 'further measures'. Because the EPC is designed to be produced at change of occupancy, it must be relevant to any occupier and it therefore must make no allowance for the particular preferences of the current occupier.
Exempt properties
Properties exempt from the Housing Act 2004 are:- Non-residential, such as offices, shops, warehouses.
- Mixed use, a dwelling house which part of a business (farm, shop, petrol station)
- Unsafe properties, a property that poses a serious health and safety risk to occupants or visitors
- Properties to be demolished, properties that are due to be demolished where the marketing of the property, all the relevant documents and planning permission exists.
Non-Domestic Energy Performance Certificates
In addition to the requirements in relation to dwellings there is also a requirement for EPCs on the sale, rent or construction of buildings other than dwellings with a floor area greater than 50m2 from 6 April 2008, that contain fixed services that condition the interior environment.Properties that are exempt from requiring a domestic EPC will generally require a non-dwelling energy performance certificate, which was also required by the Energy Performance of Buildings Directive. Commercial properties and public buildings currently account for nearly 25% of the UK's carbon emissions, contributing to global climate change.
All non-dwelling EPCs must be carried out by, or under the direct supervision of, a trained non-domestic energy assessor, registered with an approved accreditation body. DCLG has arranged for a publicly accessible central register of such assessors maintained by the Landmark Information Group.
There are three levels of building, Level 3, Level 4 and Level 5. The complexity and the services used by that building will determine which level it falls under. They are as follows:
Level 3 = Small buildings, with heating systems less than 100kW and cooling systems less than 12kW
Level 4 = purpose built buildings, with heating systems greater than 100kW and cooling systems greater than 12kW
Level 5 = Larger buildings that are complex in shape
A Commercial Energy Assessor must be qualified to the level of the building to carry out the inspection
From October 2008 all buildings including factories, offices, retail premises and public sector buildings - must have an EPC whenever the building is sold, built or rented. Public buildings in England and Wales (but not Scotland) also require a Display Energy Certificate showing actual energy use, and not just the theoretical energy rating. From January 2009 inspections for air conditioning systems will be introduced.
The A to G Scale for Non-domestic EPCs
The A to G scale is a linear scale based on two key points defined as follows:a) The zero point on the scale is defined as the performance of the building that has zero net annual CO2 emissions associated with the use of the fixed building services as defined in the Building Regulations. This is equivalent to a Building Emissions Rate (BER) of zero.
b) The border between grade B and grade C is set at the Standard Emissions rate (SER)† and given an Asset Rating of 50. Because the scale is linear, the boundary between grades D and grade E
corresponds to a rating of 100.
†This is based on the actual building dimensions but with standard assumptions for fabric, glazing and building services.
See an example.
Display Energy Certificates
Display Energy Certificates (DECs) show the actual energy usage of a building, the Operational Rating, and help the public see the energy efficiency of a building. This is based on the energy consumption of the building as recorded by gas, electricity and other meters. The DEC should be clearly displayed at all times and clearly visible to the public. A DEC is always accompanied by an Advisory Report that lists cost effective measures to improve the energy rating of the building.Display Energy Certificates are only required for buildings with a total useful floor area over 1,000m2 that are occupied by a public authority and institution providing a public service to a large number of persons and therefore visited by those persons. They are valid for one year. The accompanying Advisory Report is valid for seven years.
However, to make it easier for public authorities with multiple buildings on one site to comply with the legislation, a site-based approach for the first year (to October 2009) is allowed where it is not possible to produce individual DECs. This means that only one DEC will need to be produced based on the total energy consumption of the buildings on the site. Public bodies most affected by this relaxation are NHS Trusts, universities and schools.
The requirement for Display Energy Certificates came into effect from 1 October 2008. They were trialled in the UK under an EU-funded project also called "Display" and co-ordinated by Energie-Cités
Energie-Cités
Energy Cities, previously named Energie-Cités, is the European Association of local authorities focused on energy use. It represents 1000 towns and cities in 30 countries. From 2009 to 2011, Energy Cities is under the Presidency of the City of Heidelberg...
; participants included Durham County Council and the Borough of Milton Keynes
Milton Keynes
Milton Keynes , sometimes abbreviated MK, is a large town in Buckinghamshire, in the south east of England, about north-west of London. It is the administrative centre of the Borough of Milton Keynes...
.
The A to G Scale for DECs
This is the Operational Rating for this building. The rating shows the energy performance of the building as it is being used by the occupants.A building with performance equal to one typical of its type would therefore have an Operational Rating of 100. A building that resulted in zero CO2 emissions would have an Operational Rating of zero, and a building that resulted in twice the typical CO2 emissions would have an Operational Rating of 200.
This rating indicates whether the building is being operated above or below average performance for a building of this type.
See an example.
Criticism
EPCs have gained some political controversy, partly reflecting the housing market crisis in the United Kingdom (2008).Many in the housing
House
A house is a building or structure that has the ability to be occupied for dwelling by human beings or other creatures. The term house includes many kinds of different dwellings ranging from rudimentary huts of nomadic tribes to free standing individual structures...
industry
Industry
Industry refers to the production of an economic good or service within an economy.-Industrial sectors:There are four key industrial economic sectors: the primary sector, largely raw material extraction industries such as mining and farming; the secondary sector, involving refining, construction,...
, such as the Royal Institution of Chartered Surveyors
Royal Institution of Chartered Surveyors
The Royal Institution of Chartered Surveyors is an independent, representative professional body which regulates property professionals and surveyors in the United Kingdom and other sovereign nations....
, have criticized introduction EPCs, on the grounds of poor quality.
Wall
A wall is a usually solid structure that defines and sometimes protects an area. Most commonly, a wall delineates a building and supports its superstructure, separates space in buildings into rooms, or protects or delineates a space in the open air...
thickness at all, so that some very thick walls in older houses count the same as though they were 9" walls even though, all other things being equal, doubling the wall thickness doubles its insulation properties.
A further objection is often made concerning the quality of inspection made to produce the certificate. It cannot be invasive, so the inspector cannot drill walls or ceilings to determine the state or even existence of any insulation
Building insulation
building insulation refers broadly to any object in a building used as insulation for any purpose. While the majority of insulation in buildings is for thermal purposes, the term also applies to acoustic insulation, fire insulation, and impact insulation...
. He or she can either assume the worst (no insulation present) or rely on the householder (who may know about the matter). This can produce uncertainty about the validity of the output from his or her analysis. In addition, the procedure lacks detail - for example, draught proofing is not considered, nor the balance between ventilation
Ventilation (architecture)
Ventilating is the process of "changing" or replacing air in any space to provide high indoor air quality...
and heat
Heat
In physics and thermodynamics, heat is energy transferred from one body, region, or thermodynamic system to another due to thermal contact or thermal radiation when the systems are at different temperatures. It is often described as one of the fundamental processes of energy transfer between...
retention for the dwelling. Whether wood burning stoves are used is entirely ignored.
Finally, EPCs pose particular problems for the owners of listed buildings, as improvements such as double glazing are often barred by the controls on changes to such structures, making it difficult to rectify low ratings. Most listed building have very thick walls which aids heat retention, but which do not enter into the analysis.
See also
- Energy efficiency in British housingEnergy efficiency in British housingDomestic housing in the United Kingdom presents a possible opportunity for achieving the 20% overall cut in UK carbon dioxide emissions targeted by the Government for 2010...
- Energy policy of the United KingdomEnergy policy of the United KingdomThe current energy policy of the United Kingdom is set out in the Energy White Paper of May 2007 and Low Carbon Transition Plan of July 2009, building on previous work including the 2003 Energy White Paper and the Energy Review Report in 2006...
- Energy policy of the European UnionEnergy policy of the European UnionAlthough the European Union has legislated in the area of energy policy for many years, and evolved out of the European Coal and Steel Community, the concept of introducing a mandatory and comprehensive European energy policy was only approved at the meeting of the European Council on 27 October...
- Global warmingGlobal warmingGlobal warming refers to the rising average temperature of Earth's atmosphere and oceans and its projected continuation. In the last 100 years, Earth's average surface temperature increased by about with about two thirds of the increase occurring over just the last three decades...
- Energy White Paper