DEC assessments
Display Energy Certificates for public buildings over 250m²
Compliant DECs and Advisory Reports for schools, councils, leisure centres and NHS buildings, with renewal dates we track so you don't have to.
- 48-hour turnaround
- Elmhurst-accredited
- Fixed price quote
Get a fixed price quote
Three quick steps — about 40 seconds.
Fixed price by 9:30am on Monday
- Elmhurst-accredited assessors
- Lodged within 48-hours of the survey
- Fixed price agreed up front
- Midlands to London
One more annual deadline, off your desk
If you run a school, a council building or a leisure centre, the DEC is a small job that becomes a problem the moment it lapses. The certificate has to be on display, it has to be in date, and for larger buildings that means a fresh one every single year.
We handle the whole thing: confirming whether the building qualifies, chasing down the consumption data, producing the certificate and Advisory Report, and telling you when the next renewal is due before anyone asks.
What is a Display Energy Certificate?
A DEC shows how much energy a public building has actually used over the previous 12 months, expressed as an Operational Rating on an A to G scale. It must be displayed somewhere prominent where visitors can see it, and it comes with an Advisory Report setting out how to reduce consumption.
It is required for buildings over 250m² of total useful floor area that are occupied in whole or part by a public authority and frequently visited by members of the public. Enforcement sits with local authority Trading Standards.
Operational Rating or asset rating? The difference that catches people out
This is the single most common confusion, so here it is plainly: an EPC rates the building, a DEC rates how the building is being run.
An EPC gives an asset rating. It is modelled from the building’s construction and fixed services, and it answers the question “how efficient is this building, in theory, under standard conditions?” It is the same whether the building is packed or empty.
A DEC gives an Operational Rating. It is calculated from your actual metered gas, electricity and other fuel consumption over the last 12 months, compared against a benchmark for that building type. It answers a different question: “how much energy did this building really get through?”
| EPC | DEC | |
|---|---|---|
| Rating type | Asset — modelled | Operational — measured |
| Based on | Construction and fixed services | 12 months of real meter data |
| Triggered by | Sale, letting, new build, major alteration | Being a public building over 250m² |
| Scale | A–G | A–G, with a numerical Operational Rating |
| Validity | 10 years | 1 or 10 years, depending on size |
That is why a Victorian school with a brilliant site team can out-rate a modern building that leaves the heating on all half-term. It is also why a building can hold both certificates at once with very different grades, and neither is wrong.
What we need from you
The survey is light, but a DEC lives or dies on the data. To calculate an accurate Operational Rating we need:
- Twelve consecutive months of energy consumption for every fuel the building uses — gas, electricity, oil, LPG, biomass, district heating. Meter readings, supplier invoices or half-hourly data all work. Estimated bills are the usual source of trouble, so actual readings are far better.
- Total useful floor area, ideally from floor plans or a previous certificate. We can measure it if you don’t have it.
- Occupancy details — operating hours, weeks of occupancy per year, and the number of occupants. A school running 39 weeks is benchmarked differently from a leisure centre open 362 days.
- Separately metered or sub-let areas, so consumption is attributed correctly.
- Any on-site generation, such as solar PV or CHP, with its own output data.
We will send a short checklist when you book. If the data is spread across three suppliers and two bursars, tell us and we will go and get it ourselves.
Validity, renewal and the Advisory Report
How long your DEC lasts depends on the size of the building, and the Advisory Report runs on a different clock. That catches people out every year.
| Total useful floor area | DEC valid for | Advisory Report valid for |
|---|---|---|
| 250m² – 1,000m² | 10 years | 10 years |
| Over 1,000m² | 1 year | 7 years |
So a secondary school or a large council office needs a new DEC every twelve months, with the Advisory Report refreshed every seven. A small library or village hall gets ten years from both.
Tell us your current expiry date and we will schedule the renewal assessment in good time, every year, without you having to remember.
The display obligation
A valid DEC must be displayed in a place clearly visible to the public who visit the building — a main entrance, reception or foyer, not a filing cabinet or a shared drive. The Advisory Report does not need to be displayed, but you must be able to produce it on request.
Failing to display a valid DEC can result in a penalty, and in practice it is the kind of thing a visiting inspector notices in the first thirty seconds.
Who actually deals with this in a school
Nine times out of ten it is the business manager or bursar, not the head and not the site team. It lands with whoever owns compliance, alongside asbestos surveys, legionella testing and fire risk assessments, and it tends to surface when the SBM inherits a folder or an auditor asks a question.
If that is you, two things make this painless. First, we deal with the energy suppliers directly for consumption data if you give us the account numbers. Second, we diarise the renewal and come to you, so the DEC stops being something you have to remember in a busy September.
We work with maintained schools, academies and multi-academy trusts, where one visit can cover several sites and one invoice covers the trust.
Buildings that typically need a DEC
- Primary and secondary schools, academies and MATs
- Colleges and universities
- Council offices, civic buildings and one-stop shops
- Libraries, museums and galleries
- Leisure centres and swimming pools
- NHS buildings, health centres and clinics
- Fire, police and ambulance stations
- Courts and other government buildings
- 1
Tell us about the property
Call or send the quote form. We confirm the type, size and access, then give you a fixed price and the earliest survey date.
- 2
We book it in
One point of contact arranges access directly with the owner, tenant or keyholder. No chasing from your end.
- 3
An accredited assessor surveys
We measure the building and gather the evidence needed for an accurate rating, rather than relying on worst-case defaults.
- 4
Lodged and explained
Your certificate goes on the national register and lands in your inbox, typically within 48-hours of the visit, with plain-English advice on the rating.
Frequently asked questions
Which buildings need a Display Energy Certificate?
Buildings over 250m² of total useful floor area that are occupied in whole or part by a public authority and frequently visited by members of the public. That covers most schools, council offices, libraries, leisure centres and health centres. If you are not sure whether yours qualifies, tell us the floor area and who occupies it and we will confirm.
What is the difference between a DEC and an EPC?
An EPC is an asset rating modelled from the building’s construction and fixed services. A DEC is an Operational Rating calculated from 12 months of actual metered energy use. One tells you how efficient the building could be, the other tells you how it is actually performing. Some buildings need both, for example a council office that is being sold also needs a commercial EPC.
How often does a DEC need renewing?
Annually for buildings over 1,000m², and every ten years for buildings between 250m² and 1,000m². The accompanying Advisory Report lasts seven years for the larger band and ten years for the smaller one, so the two dates drift apart over time. We track both.
What happens if we don’t have 12 months of meter readings?
We can usually work from supplier invoices, half-hourly data from your meter operator or your energy management system. Where readings are estimated, the Operational Rating is less reliable, so we would rather get actual figures. Give us the supply numbers and account details and we will approach the suppliers directly.
Does the DEC have to be physically on display?
Yes. It must be in a place clearly visible to the public visiting the building, typically the main entrance or reception. A certificate sitting in date on a server does not meet the requirement. The Advisory Report must be kept available but does not need to be displayed.
Can you do several sites in one go?
Yes, and it is normally cheaper and quicker. For multi-academy trusts, local authorities and NHS estates we run the sites as one instruction with a single point of contact, a combined renewal schedule and one invoice.
Where we work
Bedfordshire
Buckinghamshire
Cambridgeshire
East and West Midlands
Greater London
Northamptonshire
Staffordshire
West Midlands
Ready when you are
Call, email or send the quote form. One point of contact from enquiry to certificate.
info@r2g.co.uk · Mon–Fri 8:30am–5:30pm