Article Page – EPC Assessment
EPC Assessment
This article is a comprehensive guide for any Energy Performance Certificate (EPC) Assessment, covering the core and critical details of the assessment, as well as the regional and commercial requirements.
What is an Energy Performance Certificate (EPC) Assessment?
An EPC Assessment is the process of evaluating the energy efficiency rating of a building in order to obtain the EPC proving the energy efficiency rating of the property whether residential or commercial.
EPC is primarily mandated in the UK and other European countries. Similar practices are being followed by the rest of the world but differs in regulation and calculation methods.
EPC assessments are well aligned with the trend in the UK (and global) building construction industry focusing on energy ratings, with Part L regulations and other environmental regulation becoming a huge part of being involved in the construction industry.
In the UK, the energy efficiency rating would show results ranked according to the energy performance rating of A/A+ to G with A being the most efficient. The assessment will take into account energy use, estimated energy costs, and carbon dioxide (CO2) emissions. EPCs are beneficial for potential buyers or tenants of a residential property or building to consider energy efficiency when deciding to purchase or occupying a building. A valid EPC should be produced when a new building is constructed or when an existing building is to be sold or rented to a new tenant.
Regulations could vary in each region, but the goal of the system of EPC is to be transparent how energy efficient the building is and to be intentional in reducing energy consumption and carbon emissions.
A valid Energy Performance Certificate is mandated to be acquired by a landlord or seller of a property under UK regulations. There must be a valid EPC when marketing a property and the assessment must be performed by a competent assessor.
EPCs are performed by an accredited domestic energy assessor (DEA) or on construction domestic energy assessor (OCDEA). EPC assessments does not assess the on the safety aspects or maintenance of the building services nor will the assessment confirm that the installed system is fit for purpose but should provide an estimate on the energy consumption as well as recommendations on how to improve energy efficiency.
An EPC is valid for 10 years, if property is sold or rented multiple times within that duration, there is no need to renew it every time provided that a valid EPC is available during marketing. A valid EPC can be check and found in the register website, this service can be used to find an existing EPC, display energy certificate (DEC) for a public building and air conditioning inspection certificate and report.
This article will serve as a practical guide of all the essential topics that revolve around EPC assessment, from what happens in an EPC check, the cost, the length of time it takes to conduct this assessment, the assessment criteria, a walk-through of the regional EPC assessment requirements and commercial EPC assessments.
What happens in an EPC Check?
First things first, what happens in an EPC check? In general, here are the main steps that involves in an EPC check:
Commissioning an EPC Assessment
Commissioning an Energy Performance Certificate is the first step of an EPC check. This is when the requestors who could be the landlord or business owner who is in the process of having a new building constructed, and desires to market their property for sale or look for a tenant to rent.
They will contact an accredited assessor if there is no valid EPC during marketing since this EPC rating from the documentation must be clearly shown in the advertisements of the building. Also, the energy assessor commissioned must be a member of a government approved accreditation scheme by checking the register website, or asking the assessor for their accreditation name and membership number.
Pre-assessment of relevant information about the property
Pre-Assessment of the property is necessary in the EPC check process, it allows for a preliminary evaluation of a property's energy efficiency before a full assessment on site. At times, this is done remotely just to confirm the basic details of the property.
The building owners will provide the relevant information about the building like the property include property address, the size of the building, the internal layout of the building, purpose of the building i.e. the activities performed within the zone, insulation levels, window type, heating and lighting systems, ventilation, construction type.
The assessor will analyse that information and identify the building into different zones or this may already be available from the building plan, the construction of the building fabric or the basic structural components of the building and thermal efficiency of the materials used: roof, floors, walls and glazing–all these are required for the calculation of the energy performance of the building. The energy assessor will use an EPC Pre-Assessment Checklist while conducting this. If the relevant information are not available, the energy assessor will have to survey the building.
Energy Performance Assessment
The process of assessing the energy performance of a property is only done by an accredited or trained energy assessor because it involves complex inspection.
Essentially the goal of this assessment is to obtain the Energy Efficiency Rating displayed in A to G of a building as this relates to the running costs of the building which helps a buyer or tenant make an informed decision how worth it, it is, to buy a property given its potential maintenance and energy costs. Typically energy assessors uses the software called Standard Assessment Procedure (SAP) for automated calculation of the Energy Efficiency Rating of the building but would still need the data to be manually added.
The assessment will start with data collection, the assessor will use the collected data to calculate an energy performance rating based on standardised formulas that are integrated in a software. This is done by manual measurements and visual inspection by an energy assessor to gather information on measurements of the fabric of the building, visual inspection on number of appliances or solar panels, if there are heating controls available to gather impact on energy demand, gas & electricity meters location, and heating fuel type and heating system. After this, using specialized software, the assessor will calculate the property's energy performance based on the collected data and assign an energy efficiency rating, displayed on a scale from A (most efficient) to G (least efficient) then generate an energy efficiency assessment report followed by an issuance of energy performance certificate.
Take a look at this EPC Assessment below, if you’re an energy assessor and doing the inspection manually this sample form could aide with you in walking through the different items to inspect during energy performance assessment. This document is generated using a software that features that allows the user for convenient data entry, along with conveniently adding a photo and comments in each check item during the EPC Assessment.
Free EPC Checklist Template
Use this EPC Assessment structure for yourself for free
How much does it cost to do an EPC Assessment?
The cost of EPC assessment would fall primarily on the energy assessor’s service and the administrative fees associated with EPC issuance.
The Energy Performance Certificate (EPC) usually costs between £35 and £120 (including VAT) and included is already the service of the energy assessor.
For the service of the energy assessors’ (DEA or OCDEA) – this is the time and effort to conduct the inspection, to visit the site and collect data i.e. to do visual inspection of heating systems, ventilation, insulation and others.
The factors that affect the costs will depend on the building size, complexity or location. It will take a longer time to assess a building if there is a complicated structure, or if the building has a larger size and location in terms of market rates and access to energy assessor in the area. There could also be an added cost for additional work that needs to be done to improve the energy efficiency of the property, this would depend on the result of the assessment.
The site survey would only be applicable for existing structures, if the building is new the energy assessor should have accurate plans and specifications and site visit is not necessary. Once the assessment is completed and the data is lodged to the EPC register, an EPC will be issued to the property owner or it could be selling agent.
How long does an EPC Assessment take?
Energy Performance Certificate EPC assessments usually take less than an hour to finish for residential properties, for larger size building this could take a lot longer. As we covered in this article the energy assessor will take time to do the assessment of the property’s energy performance and the time it takes to finish that will depend on the size and the complexity of the building.
There are four main steps to gain EPC
(1) Pre-Assessment of the Property
(2) Energy Efficient Assessment on Site
(3) Report Generation
(4) Client Consult or Post-Assessment
Pre-Assessment can be done remotely, and energy efficiency assessment on site is when the energy assessors would go over the property and do an inspection. Typically energy assessors when on the job, introduces the process first to the owners, survey if the site has inaccessible areas, gain their permission to take photos of the property, conduct measurement of the property e.g. wall thickness and character, window types, check insulation thickness and material type and record details of the heating and HVAC system. With this, most residential properties will take 30-45 minute range. When the assessment is complete, it would take a few more days for the EPC report to be finalised. What matters more is the accuracy of the assessment and the recommendation of the energy assessor to make sense. When the report is generated, the client or the property owners can consult the energy assessor how to make the property more energy efficient.
EPC Assessment Criteria
How would energy assessors judge if the property is energy efficient? The EPC displays the Energy Efficiency Rating (EER) of A to G where A is very efficient and G least efficient. An EPC rating is based on how much energy the building uses per square meter, this can be taken from the number of heating appliances, efficiency of boiler, heating control and how much energy it loses. All the data will be input on a specialised software that uses Standard Assessment Procedure (SAP) calculation methodology which will give out an EER in A-G.
Energy Efficiency Rating Scale for Residential Properties:
A – 92+ (very efficient)
B – 81-91
C – 69-80
D – 55-68
E – 39-54
F – 21-38
G – 1-20 (least efficient)
Each energy efficiency rating is based on the fabric of the building and its services (such as heating, ventilation and lighting). Usually EPCs will show the current and the potential rating. The rating is how the building currently scores based on the existing condition and the potential rating is how it could potentially improve if you follow the recommendations of the energy assessor for improvement.
According to a 2024 statistics, most housing units in England and Wales had a D rating (55-68) in energy efficiency and environmental impact. Most new housing is currently rated B, meaning it’s highly energy efficient. It is desirable for a property owner to have a higher rating because of its marketability but for older properties, this is quite difficult to achieve given the outdated systems in place.
Factors that could affect a low score in Energy Efficiency Rating in EPC:
1. Poor insulation of a property – This is when a property lacks adequate insulation material that would help the heat loss in winter or heat gain in warm weather. This is typical of an old home, with no roof or wall insulation and has single glazed windows.
2. Outdated heating and cooling systems – Examples of these are old gas boilers or appliances with low energy efficiency.
3. Poor Lighting – When there is inefficient light bulbs and lack of efficient lighting controls
4. No renewable energy – Absence of solar panels or other renewable energy sources
Regional EPC Assessment Requirements
In this section, let’s look at the regions in the UK and the different regulations in assessment requirements and approaches regarding Energy Performance Certificates. It should be noted however that all of these regions have similar principles “to make energy efficiency of buildings transparent by using an energy performance certificate (EPC), to show the energy rating of a building, when sold or rented out and recommendations on how to improve energy efficiency”.
Let’s go through their key differences per region:
England and Wales EPC Requirements
The region of England and Wales are regulated by Ministry of Housing, Communities and Local Government. Rules are:
- Landlords must get a new EPC every 10 years when renting out a property
- EPC is required when a new building is constructed
- If the commercial property is frequent by the public and is larger than 500m2 EPCs must be displayed
- >EPC rating must not be lower than rating E (39-54 EER)
Scotland EPC Requirements
Mandates are coming from "Energy Performance of Buildings (Scotland) Regulations 2008”
Some key rules are:
- All residential and non-domestic buildings must have an Energy Performance Certificate (EPC) when sold or rented to a new tenant
- A minimum of EPC Rating C (69-80 EER) must be achieved for all privately rented properties
- EPC is valid for 10 years
- For non-domestic buildings over 1000 square meters, an Energy Action Plan must also be produced when selling or renting.
Northern Ireland EPC Requirements
Northern Ireland regulations are regulated by Department of Finance in Northern Ireland.
The same requirements with England and Wales:
- All residential and commercial buildings constructed or being marketed must have an Energy Performance Certificate
- >EPC should provide ratings of A-G and recommendations for improvement
- Public Buildings must display energy certificates
Commercial EPC Assessments
Commercial properties are properties that are considered non-domestic or non-dwelling meaning that it’s not suitable for residence but used for other matters such as shops, schools, hospitals or factories. The principle of the EPC assessment for commercial building are the same with residential building, its ultimate goal is to reduce energy consumption and improve the energy performance of a building.
The EPC for commercial properties must be produced by accredited energy assessors and an EPC score would relate to the running cost of a commercial unit. EPC is required when a commercial building is constructed, sold or rented out, with a total useful floor area greater than 2,500m2. The rating is also shown on an A+ to G rating scale which is applicable to electrical appliances. A+ would indicate it is very efficient or under 0 CO2 emissions and G less efficient with over 150 CO2 emissions.
Energy Efficiency Rating Scale for Commercial Properties:
A+- Under 0 (Net Zero CO₂ emissions)
A - 0-25
B - 26-50
C - 51-75 (61 | C)
D - 76-100
E - 101-125
F - 126-150
G - Over 150 (Highest CO2 emissions)
The energy performance of the building is shown as a carbon dioxide (CO2) based index, this comes from the energy used to operate it (heating, cooling, lighting) – the operational emissions of a building. The EPC of a non-dwelling must contain reference information (certificate reference number, address of the building, and date of issue), competent and registered energy assessor details, inclusions of cost-effective recommendations to improve the energy ratings.
In Summary
This article about EPC Assessment was a brief guide on the important aspects of Energy Performance of a property, it covers the legal obligations of business owners who are in the process of constructing a new building or marketing for sale or rent an existing building, it also provides the relevant cost information on EPC.
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