Energy Performance Certification
An Energy Performance Certificate (EPC) shows an asset rating which is a numerical and colour
coded indication of the energy performance of the building based on its standardised use. Energy
Performance Certificates include these benchmarks to enable buildings to be compared with one
another.
Asset ratings are calculated taking into account the energy performance of the building’s fabric and
its services (i.e. heating, cooling, hot water, ventilation and lighting).
What Other Information Is Provided?
EPCs must be accompanied by a Recommendations Report, which provides recommendations for the
improvement of the energy performance of the building. This provides advice and guidance,
following an initial assessment, of the best options for improving the asset rating of a building.
Who Can Produce An EPC?
An EPC must be prepared by an energy assessor who is a member of a Government approved
accreditation scheme. These schemes also provide the service to formally lodge an EPC onto the
central database. CPS is BRE approved
How Long Is An EPC Valid For?
An EPC is valid for up to 10 years – unless a refurbishment of the buildings fabric or services has
been undertaken in which case a new EPC can be commissioned to provide a more up-to-date EPC
for the relevant building.
What If There Are Separate Units Within A Building?
An EPC for a separate unit within one building may be based on the assessment of a representative
unit. If there is a common heating system, the whole building can be certified as one. An EPC can
also be commissioned on a part of a building; for example where there may be several floors leased
to various tenants and one becomes vacant an EPC can be undertaken on the vacant part of the
building in isolation.
Which Buildings Do Not Require Certification?
The following types of property are all exempt from the process:
• Lease renewals, lease restructuring (unless the floor is modified or the space refurbished) or
surrendering.
• CPOs – Compulsory Purchase Orders
• Buildings that are less than 50m2 in size – those that are temporary structures or where
evidence can be provided that the building is set for demolition.
• places of worship.
• certain buildings with low energy demand.
• buildings where energy is not used in conditioning the internal climate in terms of heating,
ventilation or cooling.
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Index:
EPC as a Requirement Page 2
Display Energy Certificates Page 3
Energy Performance Certification for the home Page 4
SBEM Calculations and Rating Page 5
Part L2 Compliance Page 6
Dates for Statutory Compliance Page 7
Information required for EPC and SBEM calculation Page 8
How to achieve a Low Carbon building Page 9
Helpful Glossary Page 10
EPC As A Requirement
Our buildings are responsible for almost 40% of the UK's energy consumption and carbon emissions.
The EU Energy Performance Of Buildings Directive (EPBD) 2002/91/EC has been introduced to all
member states as a step forward towards improving energy efficiency in buildings. In simple terms,
these certificates allow greater transparency in terms of a buildings energy usage/emissions ratings.
Even comparatively minor changes in the energy performance or the way we use each building
would have a significant effect in reducing energy consumption and hence carbon emissions,
reducing energy consumption attributable to buildings is now a key policy objective.
These latest measures introduced to improve the energy efficiency of buildings, include:
• Introducing Energy Performance Certificates for properties providing A-G efficiency ratings
with A being the best and G being the worst and recommendations for improvement,
although compliance with these recommendations is not obligatory.
• Requirement for Public buildings over 1000m2 to have Display Energy Certificates
• Requirement for the inspection of air conditioning systems.
EPCs as part of this legislation should become become an integral part of future investment
decisions or a reason to occupy a building.
From the 1 October 2008 all homes and commercial buildings which use energy to condition there
interior climate when sold, built, modified (fabric or services) and rented will need an Energy
Performance Certificate or EPC. Public buildings occupied by authorities and institutions will also
need Display Energy Certificates (DECs) which will indicate actual energy consumption or perceived
consumption in the case of new buildings.
The EPC must be provided by the seller when the building is sold or by the landlord in a building that
is to be let. For new or modified buildings the EPC must be provided by the person carrying out the
work (i.e. the developer). An EPC will be valid for ten years.
The Recommendations Report will include money and energy saving advice. EPCs will mean a
benchmarking facility for comparison of buildings and there energy performance, a monitor and
control for emissions and it also should lead to greater emphasis by buyers and clients looking to
lease buildings on energy performance.
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Display EPC Certificates
Public authorities and institutions that provide public services to a large number of persons, who
occupy space in a building with a total useful floor area greater than 1000m2 and are visited by the
public, must have on show a valid Display Energy Certificate (DEC) at all times and have a valid
advisory report in their possession.
A DEC shows an operational rating (numerical indicator of the actual annual carbon emissions from
the building) which conveys the actual energy used by the building as well as the asset rating (if
available by way of an EPC) showing the intrinsic performance of the building. The advisory report
will contain recommendations for improving the energy performance of a building.
Only Public authorities or institutions providing Public services (those services traditionally
associated with Local or National Government) occupying a building must display a DEC. Other
private occupants of the same building are not required to display a DEC.
Such buildings are:
• Central or Local Government offices
• NHS Trusts
• Places Of Education
• Courts and Prisons
• Institutions providing public services including museums, art galleries and swimming pools.
These buildings will be required to display the DEC in a prominent place (no smaller than A3 in size
is recommended) and should include the operational rating of the building based on actual statistics
(utility bills and costings) of the current and previous two years (if available). The DEC basically
provides information as to whether the buildings energy performance is improving or not.
If it is a newly constructed building the details required to produce the DEC rely on information
produced in the SBEM and the Energy Performance Certificate.
The purpose of introducing Display Energy Certificates is (DECs) is to raise public awareness of
energy use and to inform visitors to public buildings about the energy use of a building.
A DEC is valid for one year and must be updated annually whilst the Advisory Report is valid for a
seven year period.
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Energy Performance Certification for the Home
An Energy Performance Certificate is a consumer friendly rating of a homes energy efficiency based
on a number of factors relating to energy usage with regard to:
• Heating
• Water heating
• Construction type
• Window type
• Property dimensions
• Insulation levels
• Lighting
Properties are rated on an A to G scale with A being the most energy efficient and having the lowest
carbon emission figure and thus the lowest negative impact on the environment, an EPC allows for
comparisons to made between the energy efficiency of different properties.
The EPC will include:
• The energy efficiency of the dwelling
• The carbon emissions figure
• The cost of lighting, heating and hot water per annum
• Recommendations report on ways to improve the home's energy efficiency
By making energy saving improvements you can not only reduce your bill costs but also reduce your
carbon footprint because you will also be producing less greenhouse gases through reduced energy
usage.
Building Regulations specify standards for the energy performance of new homes to which builders
must adhere. Upon completion it is the duty of the builder - or person reponsible for construction -
to obtain an Energy Performance Certificate (EPC) for the building, provide it to the new owner and
notify the local authority building control officers or approved inspectors once this has been done.
Building Regulations stipulate the precise point by which this procedure must be completed. From
April 6th 2008, building control will only issue a final completion certificate once they are satisfied
that the EPC has been properly produced and provided to the relevant party.
CPS can give you an energy performance rating for your home. Whether it's a requirement because
you are selling, renting or you simply are curious as to your home’s performance.
From April 6th 2008, an Energy Performance Certificate is required whenever a residential property
is constructed, sold or rented.
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SBEM Calculations
SBEM (Simplified Building Energy Model) is a tool introduced by Government in accordance with
Part L Building Control Regulations for the calculation of the energy performance of new and existing
commercial buildings.
When Are SBEM Calculations Needed?
From October 1st 2008 all commercial buildings will now require an SBEM calculation on build, and
an Energy Performance Certificate when applying to a let or sale.
What Timeframes For Calculations Are We Looking At?
If you are working to a deadline we will endeavour to supply you with an SBEM calculation or Energy
Performance Certificate within 14 to 21 days.
Can You Explain SBEM Calculations For The Purpose Of Part
L Compliance?
With regard to Part L compliance there are two stages to the calculation.
The first stage is at the design stage; this needs to be submitted to your Building Control Body or
Approved Inspector when you make your Building Control Application
The second stage is at the as built stage when the building is completed and an SBEM calculation
which confirms that the building meets the required standards for Part L is produced and presented
to your Inspector.
If any changes have been made to the building since the design stage and calculation then the
Inspector may request a re-calculation of the asset rating based on the change in specification of
the building.
The Rating Process
The energy assessor will need to understand the internal layout of the building and for what
purposes it is designed to be used. Even if detailed drawings of the building exist it is still likely that
a site inspection will be required to confirm the building services and construction details. It is
important to understand not only the specific dimensions of the building but also; the actual usage
of the space (as this dictates the relative energy usage of each part of the building) and the building
services including types of lighting, heating, cooling and ventilation in use in the different areas of a
building. All of this information is applied to the modelling software.
The Calculation Procedure
The Government approved software used to model a building and calculate an EPC is provided by
the Building Research Establishment and is called iSBEM, the Simplified Building Energy Model. More
complex buildings will almost certainly require other dynamic simulation modelling solutions (DSMs)
to be used as SBEM cannot currently model complex building elements such as atria, night cooling
etc. The SBEM tool has been available for almost two years and complies with Government
regulations. Data is entered into SBEM using the iSBEM software interface, this subsequently
produces your EPC, recommendations report or Part L compliance calculations.
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Part L2 Compliance
Part L Building Regulations legislation can be confusing and time consuming, especially if you have
not had to meet these requirements before. At National Energy Rating we know you need an easy
straight forward approach, with sensible and practical advice.
A new revision of Part L (Conservation of Fuel & Power) of the Building Regulations came into force
in April 2006. The regulations relating to non-domestic buildings are in two parts:
• Part L2A governing new build non-domestic buildings
• Part L2B governing works on existing buildings. Extensions to existing buildings are assessed
using the rules set in Part L2A.
Compliance with Part L2A can now only be demonstrated using a National Calculation Methodology
(NCM) such as SBEM. The familiar elemental method no longer applies.
The NCM compares the total energy consumption of the building and its services, expressed as
carbon dioxide emissions of the building, ("Building Emission Rate" or BER), with a target value
("Target Emissions Rate" or TER), derived from calculations for a "notional building", which is similar
in size, shape and use class of the evaluated building.
The "Target Emissions Rate" requires an Improvement Factor to be applied to the notional building's
emissions according to the building services strategy to be used, ranging between 23% for naturally
ventilated buildings to 28% for mechanically ventilated and air conditioned buildings.
In addition to this overall energy consumption requirement, minimum thresholds are set for:
• thermal performance of individual fabric elements
• building services plant efficiencies
• envelope air tightness
Provision is made for credits to encourage the use of LZC (Low and Zero Carbon) technologies, and
there is a further requirement to include means to limit solar gains in summer.
Building Control Part L approval is now a two stage process, with design calculations demonstrating
theoretical compliance submitted pre-construction, and a second submittal confirming the actual
calculated performance of the building post-construction.
All buildings are subject to air tightness testing to demonstrate that the assumptions used in the
energy calculations have been achieved in practice.
Building Control also now require verification, post construction, that metering is installed, building
services are fully commissioned and a building Log Book has been prepared to provide the building
owner with relevant information to enable him to operate his building effectively.
The impact of the 2006 changes to Part L are that building design teams now have to optimise
building fabric, geometry and services at an early stage to achieve these demanding energy
efficiency standards.
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Dates For Statutory Compliance
The dates for the phasing in of the Energy Performance Of Buildings Directive is provided in the
table below:
• 6 April 2008 EPC's required on construction for all dwellings.
EPC's required for the construction, sale or rent of buildings other than dwellings with a floor
area over 10,000 m2.
• 1 July 2008 EPC's required for the construction, sale or rent of buildings other than
dwellings with a floor area over 2,500 m2.
• 1 October 2008 EPC's required on the sale or rent of all remaining non-dwellings
EPC's required on the construction, sale or rent of all remaining buildings other than
dwellings. Display Energy Certificates required for all public buildings >1,000 m2.
• 4 January 2009 First inspection of all existing air-conditioning systems over 250 kW must
have occurred by this date.
• 4 January 2011 First inspection of all remaining air-conditioning systems over 12 kW must
have occurred by this date.
Additional legislation is already under review and is sure to follow. If you want to be kept up to date
contact us for further information on any proposed legislation affecting the commercial sector and
when it is due to come into force.
An EPC for a building that is to be sold or rented out must be provided at the earliest opportunity.
You do not need to provide an EPC if you have reasonable grounds to believe that the prospective
buyer or tenant cannot afford or is not serious about the transaction or you are not likely to be
prepared to sell the building to them.
What Are The Penalties For Not Having An EPC?
Local Trading Standards Officers have the powers to enforce the regulations. Fines for the failure to
produce an EPC can range between £500 and £5,000 depending on the properties rateable value
- and an EPC will still be required.
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Information Required For EPCs and Part L2 Compliance
Assessment (SBEM)
To facilitate the preparation of an EPC or carry out a Part L assessment for a new building, the
following detailed information will be required:
• Project name, building type, address
• Owner details including name, telephone number, and address
• Fully dimensioned plans, elevations and sections
• Details of all building fabric elements constructions, types and where known U values.
• Details of thermal bridges if available
• Glazing configurations ( single/double/triple/air gaps/frame type/glazing type)
• Door types and constructions
• External shading provisions
• Details of building services by room including heating, ventilation and cooling if applicable
• Schematics of building services systems and room by room schedules of services
• Specific fan power for all mechanical ventilation systems
• Boiler type, fuel type and seasonal efficiency
• Fuel type ( Natural gas/LPG/Biogas/Oil)
• Domestic Hot Water system type, fuel type and seasonal efficiency
• Design air permeability standard m3/m2/hr at 50 Pa
• Details of plant efficiencies where these have been selected or specified
• Details of lighting lamp types and control provisions and whether there are air extracting
luminaries
• Provisions for metering, including monitoring and alarms for out of range values for all
systems
• Electric Power Factor
• Details of LZC systems including photovoltaics , solar energy, wind generators , CHP
Where information is already available from the facilities manager for existing buildings the process
of EPC preparation can be accelerated, with the survey limited to verification of the information.
Where there is only limited information available, a full survey will normally be required.
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How To Achieve A Low Carbon Building
Adopt an integrated multi-disciplinary team approach from the outset, and consider the energy
implications of design decisions from the outset. CPS can advise at all stages of the build.
The most important principal is to design the building wherever possible to reduce the total energy
demand.
Do this by:
• Wherever practicable avoiding air conditioning which can add 50% to the total energy
consumption in buildings.
• Design the envelope to maximise the use of natural lighting and ventilation whilst avoiding
excessive solar gain.
• Design the envelope to minimise air permeability.
• Minimise the demand for hot water by selection of reduced flow sanitary fittings
• Use heat recovery
• Keep building services systems simple, so that they are easy to commission, maintain and
manage, but ensure that there are adequate controls available to minimise energy wastage,
and incorporate monitoring and alarms to inform maintenance teams.
• Select efficient plant and do not oversize it. Plant runs most of the time at part load which is
always less efficient than at full load. Oversized plant is less efficient for more of the year
than correctly sized plant.
• Select environmentally friendly fuels and make use wherever possible of Low and Zero
Carbon energy sources.
• Benchmark designs against good practice.
• Include an appropriate level of metering and sub metering to permit measurement of energy
consumption.
Collectively CPS can devise and implement a comprehensive service solution to enable your building
to achieve its full energy performance potential but at minimum cost and disruption to your
business. Combining our strong property experience with our environmental consultancy expertise,
we provide all the information you require to make the right decisions and ensure maximum profit
for your business.
Even though it is not yet mandatory to render your property energy efficient, investing can lead to
lower energy costs, a rise in the value of your property, elimination of expensive remedial measures
at a later date should government legislation become more stringent and avoidance of future
increases in taxes based on environmental sustainability factors.
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Helpful Glossary
Whether you are a newcomer to energy rating, or just need a reminder on a specific word
or acronym, our aim here is to provide straight forward explanations for some of the
technical ‘jargon’ most commonly used within the energy rating sector.
For quick reference, we have listed in alphabetically order an explanation of these words
and acronyms.
AR Advisory Report
CEA Commercial Energy Assessor
DEC Display Energy Certificate
DSM Dynamic Simulation Modelling is a software tool that models energy inputs and outputs for
different types of building over time. In certain situations, SBEM, will not be sophisticated
enough to provide an accurate assessment of a buildings energy efficiency. In these cases
Government approved proprietary dynamic simulation models may be used. Communities
And Local Government will provide such an approval.
Energy Assessor An energy assessor is an individual who is a member of an accreditation
scheme.
Energy Assessment This refers to the preparation and issuing of an Energy Performance
Certificate (EPC) and the accompanying Recommendation Report (RR) and the carrying out
of any inspections undertaken for the purposes of issuing the EPC or RR.
EPBD European Performance Of Buildings Directive
EPC Energy Performance Certificate
HVAC Heating, Ventialtion, Air Conditioning
OR Operational Rating (required for DECs)
NOS National Occupational Standards are standards for Energy Assessors that are approved by
the United Kingdom Coordinating Group of National Occupational Standards Boards, as amended
from time to time.
RdSAP is software intended for use by Energy Assessors in producing energy
assessments for existing dwellings where plans and other constructional details are unavailable.
Only approved versions of RdSAP software may be used. It comprises the SAP calculation engine
with an input system that enters default data based on an energy assessor’s observations from a
visual inspection, although data from other sources may be acceptable.
RR Recommendations Report - issued with EPC
SAP is the national calculation methodology for determining energy use for heating, hot water
and lighting for dwellings.
SBEM SBEM provides an analysis of the energy consumption of buildings other than dwellings,
used in support of the National Calculation Methodology (NCM) and the Energy Performance of
Buildings Directive (EPBD). The calculation method is also used in determining CO2 emission
rates for new buildings for compliance with the new Part L of the Building Regulations
(England and Wales) and equivalent Regulations in Scotland and N Ireland.
The Register is the central databank, created and maintained by the Secretary Of State’s
approved contractor, to lodge the Energy Performance Certificates and recommendations
reports. Each document entered onto the register must be registered under a unique reference
number, and shall not be altered once registered. Any document or data entered onto the register
must be kept on the register for a period of at least 20 years beginning on the date on which the
document is entered onto the register.