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1a) Is an EPC a legal requirement?

The EPC is required by law when a building is constructed, sold or put up for rent. You will also need an EPC if you are applying for a feed in tariff for solar panels. The certificate must then be made available to prospective buyers, free of charge. It also goes on the national EPC Register, where it can be easily accessed.

As of 1 April 2018, all private rental properties in the UK must have an Energy Performance Certificate with a minimum rating of E. Without this, landlords won’t be allowed to rent out their properties to new tenants or renew existing rental contracts.

There are exemptions to the EPC requirement, however, such as:

  • resident landlords who only let out a room

  • listed buildings

  • places of worship

  • holiday homes let out for less than four months of a year



1b) What happens if i do not have an energy performance certificate?

The penalty for failing to make an EPC available to any prospective buyer or tenant when selling or letting non-dwellings is 12.5% of the rateable value of the building, subject to a minimum penalty of £500 and a maximum of £5,000. The EPC will still be required. The penalties for residential dwellings are expected to be £24000 per non-compliance; however, this may be adjusted up or down closer to implementation.


1c) What does this mean to you?

If you are offering any accommodation for sale or let (this includes sub-letting) you will need an EPC. An EPC should be provided to a prospective buyer or tenant at the earliest opportunity and no later than when a viewing is conducted or when information is provided about the building or in any event before entering a contract to sell or let. As a seller or landlord, you are responsible for ensuring that the property has an EPC, even if an agent is acting on your behalf.


1d) Do I need a new EPC if I make a change to my property?

You are not required by law to have a new EPC every time you make a change to your property.  You may however choose to update your EPC if you feel that it would make a significant improvement to your rating.


1e) Does the property need to achieve a certain rating?

It depends on what you are using the EPC for...

  1. For rental properties, from the 1st April 2018 changes to legislation make it unlawful to let residential or commercial properties with an EPC rating of F or G.  This applies to new tenancies after that date.  From 1st April 2020, this rule will be extended to apply to all residential properties with existing tenancies in place.

  2. For sales, the requirement is to have an EPC, regardless of what rating is achieved.

  3. For renewable energy grants and feed in tariffs, you will need to find out from the specific scheme as to whether a rating needs to be achieved.


2a) What does an EPC survey entail?

An accredited and qualified Domestic Energy Assessor will visit your property to carry out the survey. This will usually take less than an hour. They will make notes on your property, from your heating systems, to insulation, to the size of your living space. The assessor may take photographs of various elements of your property that have been surveyed. Their survey will be extensive, from a visual inspection of your windows to a head and shoulder inspection of your loft space, if possible. The biggest part of the calculation for the EPC comes from the heating system in your property. This includes making notes of all forms of heating you have, the number of thermostatic radiator valves fitted in your house, your heat controls, and such like. The assessor will also jot down some measurements, such as the height of the main

What information is on an EPC?

Although the focus is on the rating itself, there’s also a lot of practical information, including: -

  • The estimated energy costs of the building

  • The estimated energy savings that could be made

  • The EPC also offers suggestions on the best ways to increase energy efficiency and save money on energy bills, e.g.: 

  • Increasing loft insulation

  • Adding double glazing

  • Adding cavity-wall insulation

  • Draught proofing

The EPC offers an estimated cost range for each option, plus the potential annual savings they could generate. It also lists each element of the home and its individual energy.


3a) How long are EPCs valid for?

An Energy Performance Certificates is valid for 10 years so it can be re-used if a dwelling is let or sold again during that time. However, it is recommended that a new one is completed every time works are carried on the property which could improve the energy performance i.e. boiler installation, external wall insulation, loft insulation, double glazing, installation of fan-assisted storage heaters, etc.



3b) How can I make a booking?

The best way of making your booking is by using our easy-to-use                                .              You will be asked to enter all the relevant details regarding your property and make payment online.



3c) Once I book online what’s the next step?

As soon as the booking has been made and paid for online you will receive an order confirmation email along with a receipt for your payment (if your email is not received please check your spam or junk folder). You can then expect to hear from our local assessor usually within 24 hours of the booking to arrange an assessment time.

Once the Energy Assessor has visited the property you will have your report completed normally within 24 hours of the property being assessed. You will be emailed when your EPC is ready for download (again please check your spam folder) and a copy will also be placed on the governments EPC Register.



3d) How long will the inspection take?

On average the inspection will take 30-60 minutes, although this can vary depending on the size and shape of the individual property.


3e) Do I need to be at the property during the inspection?

You don't need to be present during the inspection.  If you would like us to, we are happy to collect keys from your estate/letting agent, in order to carry out the inspection.



3f) What areas of the property do you need to access during the inspection?

The Assessor will need to gain access to all areas of the property, including the loft space, heating systems, meters, garage, airing cupboard, basements, and every room within the property.  The Assessor is required to take photographs of these aspects, so good access must be provided.


3g) Do I need to prepare anything before you carry out the EPC?

Depending on your individual property, we may ask to see some written documentation.  If you know you have had cavity wall insulation added to your property since it was built, please have your Cavity Wall Insulation Guarantee Certificate to hand if you have one.  Likewise, if you have any Building Regulation Completion Certificates (for conversions, extensions or loft conversions), MCS Certificates (for renewable energy systems) or FENSA certificates, please have them available on the day.



4) When can I expect my EPC?

The energy performance certificate is generated using a government-approved software methodology called RDSAP – the Reduced Data Standard Assessment Procedure for existing properties or SAP for new-built dwellings.

Once the survey has been completed, the details are entered into a software, before being uploaded onto the national database.

Once the EPC is lodged it will appear on the national EPC register which has open access.




4b) How will I receive my report once it is complete?

​Please note that we cannot make your EPC available until we have received full payment for this service.  Once your report has been finalised by the Assessor, we will send you your draft report by email.  We are happy to send a copy to your agent as well if you would like us to.  The report can also be obtained on the EPC Register, once it has been lodged by the Assessor. 




5) What if I don't want my details to appear on the public database (EPC Register)?

Once the report has been lodged by the Assessor, you can fill out an online form to Opt-Out of remaining on the EPC register if you would like to.



5b) I have had my report why does it say ‘Insulation Assumed’ on it?

Whilst at the property the assessor will gather the required data and evidence to support his findings. The householder should have any evidence to support the presence of insulation to the floors, walls and roof available for the assessor at the time of the inspection. If there is no evidence, then the assessor will simply state in the EPC software ‘insulation unknown’. The software will then make assumptions based on the age and construction of the building as to whether insulation is present. Next to this assumption the word ‘assumed’ will appear. This is not stating that insulation is definitely /definitely not present but is simply an assumption made by the software.


5c) I have found an insulation Certificate, but my EPC has been completed. Can my EPC be updated?

Once complete an EPC cannot be updated. If insulation evidence comes to light after the EPC is lodged the old EPC can be cancelled and a new one produced. There will be a charge for this.


6)What is the difference between a domestic and commercial energy assessor?

You may have heard of the Commercial EPC before, and thus you may be wondering what the difference between the two is. A commercial building is any type of building that is used for commercial purposes, such as shopping malls, warehouses, retail stores, and office buildings. However, this is not the only difference between the two Energy Performance Certificates. Commercial EPCs are more expensive, and this is because Commercial Energy Assessors need to have the ability to analyse equipment ratings from the site and thus, they need to be more technically qualified. A Commercial EPC survey takes a lot longer, taking around two hours, if not longer, and this is because it is much more intensive.


7)What if my property is a new built?

If your property is newly built, then a separate energy performance certificate will be required which is called an On-Construction EPC certificate. On-Construction EPCs, also known as SAP EPCs, are required before a new-built can be certified by Building Control.

On Construction EPCs are produced off-plan using full SAP (standard assessment procedure) which is more accurate than Redcap as used in existing dwellings because all the build specification is available to the assessor.

To book an SAP EPC, please call us on 020 8166 4157.



8)Why choose Thames Valley EPC ltd for your EPC?
An EPC must be produced by a qualified Domestic Energy Assessor or a DEA, registered with a government authorised accreditation scheme.


Thames Valley EPC is your assessor organisation fully accredited by Elmhurst Energy to assess your property and produce the EPC certificate.

At Thames Valley EPC, we promise to provide a fast and accurate service to not only ensure that you are within the legal requirements as a landlord or agent but also to recommend ways in which you might reduce the running costs of your property. We are fully certified, giving you the peace of mind that you will get accurate information and a professional service from assessors who are fully covered with Public Indemnity and Public Liability Insurance.




This article details each aspect of the EPC and what it means in layman’s terms.




Section A

Dwelling type: This is the classification of the property (Flat, Detached House, Semi Detached House etc). For the purposes of the EPC any property that has another property above or below it is classified as a flat. This classification does not have any effect on the result of the EPC as this is based on actual measurements of property volume and external wall areas etc.

Date of assessment: This is the date that the DEA visited the property.

Date of certificate: This is the date that the certificate was lodged on the government database.

Reference number: This 24-digit number is unique to each certificate. It can be used at any time during the certificates ten-year life span to retrieve the document from the government database. It is worth noting that when using this number, you will always need to include the hyphens.

Type of assessment: RDSAP, existing dwelling is the technical term for your domestic EPC. RDSAP refers to the 'Reduced Data Standard Assessment Procedure', the methodology that is used to produce your EPC rating.

Total floor area: This is the total floor area of your property measured in square meters. Outbuildings are not included in the EPC survey unless they are heated and habitable.


Section B

This section looks at your estimated energy costs and potential savings. This energy cost analysis only looks at proportion of your energy usage that goes towards heating, hot water and lighting. The EPC does not look at how the property is used on a day to day basis, so appliance use is not included in this figure.

These figures do not consider any electricity generated by micro generation such as wind turbines and solar panels.

Red Header: This shows an estimate of your energy costs over a 3-year period.

Green Header: From the data gathered this is an estimate of how much money could be saved on your energy bills, over 3 years if you follow the recommendations in the report.

Blue Header: This shows an estimate of your current energy costs and potential savings over a 3-year period, broken down into the 3 separate energy use categories; Lighting, Heating and Hot Water.


Section C

This Section shows you the EPC Graph, which is what comes to mind when most people think of the EPC. The graph displays two ratings, current and potential. The ratings are based on a score from 0 to 100, with 100 being the most energy efficient and 0 being the least. The ratings are also split into bands of A to G.

Current: Is the buildings actual EPC rating as of the date of the survey.

Potential: Is the rating that the property would achieve if all of the recommendations that the report suggest on page 3 were carried out.


Section D

This section shows you the most highly recommended measures you could undertake to improve your homes energy efficiency.

Recommended measures: Lists the measure in question.

Indicative cost: This gives an estimate of how much the energy saving measure is likely to cost to implement.

Typical saving over three years: This is the estimated amount of money that the recommended measure will save the property in energy bills over a three-year period.





Property Inventory

What is a Property Inventory?

An inventory is a report that provides an accurate photo graphic & written record of the condition and contents of a property at the beginning of a tenancy.

Why Use Photographs in the Inventories?

Our experience shows the best way to avoid misinterpretations and disagreements is by combining the reports with photographs. Marks, scratches, stains and damage are photographed and serve to complement the written description and so avoid unpleasant disputes.

Can you email us Inventory reports when complete?

We issue all reports through emailing the PDF version of our report to the instructing party so this format cannot be manipulated. The email address should be provided when the job booking is taken.

What do you charge for a property Inventory?

We charge depending on the size of the property, whether it is furnished or unfurnished and whether it is a flat or a house. For a quote on a particular property or our standard fees

What information do you require to take a job booking for a property Inventory?

We require the following information:

  • the proposed date

  • property address with full postcode

  • number of bedrooms, reception rooms and bathrooms with/without garden

  • confirm if property is furnished/unfurnished

  • confirm if the property is a house or a flat

  • who manages the property?

  • tenants contact details

  • collection point for keys and paperwork.

Please call us with these details so we can suggest a time for the inspection before calling the tenants to arrange the sign-up time.


FLOORPLANS/reading council HMO floorplans

What type of floorplans is it?

We offer hand drawn floorplans, 2D and 3d floorplans


How long does it take?


Approximately 1 – 3 hours depending on size of property





Commercial Energy Performance Certificates

  • How much does a commercial EPC cost?

Our fee for a commercial EPC is quoted individually per property, depending on the size and complexity of the building. ​

  • How long is a commercial EPC valid for?

The commercial EPC is valid for 10 years from the date of the assessment (as shown at the top of the report).


  • Are commercial EPCs kept on a national database?

Yes, the most recent commercial EPC that has been lodged for a property can be viewed on the online database: 




Gas safety certificates

Is it a legal requirement?

For a landlord, it a mandatory. It lasts 12 months?


How long does it take?

1 hour approximately


Can anybody issue a gas safety certificate?

Only a qualified ‘gas safe’ registered engineer can issue gas safety certificates



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