Hospitals don’t switch off. Nor do 24/7 logistics sites, factories with always-on distribution boards, or hotels through occupancy. For buildings like these, a thermographic survey is the only way to check the electrical installation while it stays live, picking up faults that a standard EICR cannot catch under switched-off conditions. There’s no recommended interval for it in UK guidance. The decision to book one is driven by the risk profile of the installation, the age of the kit, or what an insurer or sector standard expects.
Some FM teams treat the survey as the diagnostic step before an EICR. Others book it because parts of their building can’t realistically be powered down. Either way, the question isn’t whether the survey is useful, it’s whether yours is overdue.
What Does a Thermographic Survey Show?
A thermographic survey (sometimes called thermal imaging) uses a powerful infrared camera to scan live electrical components and pick up heat signatures that flag potential issues before they cause failures.
Because the survey is non-disruptive and systems don’t need to be switched off, it’s a popular option for schools, hospitals, prisons, and other sites where powering down isn’t practical.
A thermographic survey typically identifies:
- Overheating cables or motors
- Loose, worn, and corroded connections
- Damage and wear to electrical insulation
- Overloaded fuses
- Blown fuses, which show cooler than expected and often appear blue on the image
Faulty components get spotted and flagged for remedial work before they become a problem. That’s the preventative value of the survey, and the reason it pairs so well with a standard inspection.
When Does Your Commercial Building Need a Thermographic Survey?
There isn’t a fixed timetable, so the practical question is whether your building falls into one of the scenarios where a survey clearly adds value.
Consider one when:
- Powering down isn’t realistic. This includes hospitals, schools during term time, universities, hotels, 24/7 retail and logistics sites, and factories with always-on distribution boards.
- The installation is ageing or heavily loaded. Older boards, motors, and cabling often show heat issues long before they show electrical faults on a standard inspection.
- A fuller picture is needed alongside an EICR. A thermographic survey is often booked before or alongside the EICR to cover sections that can’t be tested under switched-off conditions.
- An insurer or sector standard expects one. Some commercial policies require thermographic evidence as a condition of cover for higher-risk premises.
- You manage a multi-site portfolio. Consistent diagnostics across locations make it easier to spot patterns and prioritise the sites that need attention.
For the wider compliance picture, our UK electrical compliance deadlines guide sets out which tests apply to your building and when.
How Does an Electrical Thermographic Survey Work with Your Commercial EICR?
A commercial EICR tests fixed wiring under controlled conditions and is the backbone of electrical compliance for any business property. It’s thorough, but it has one practical limitation: some installations can’t realistically be powered down for inspection.
Live factory distribution boards, hospital wards, server rooms, and hotels during occupancy are common examples. Switching them off, even briefly, isn’t always possible.
An electrical thermographic survey covers exactly those areas while the system stays running. Used alongside an EICR, it gives the building a fuller picture of electrical health without disrupting day-to-day operations.
What Does a Thermographic Survey Cost, and What’s in the Report?
Pricing is bespoke. Cost depends on how much time the engineer spends on site and how many images need to be surveyed, so a small office and a multi-site logistics operation will quote differently.
The deliverable is an easy-to-digest report with photos showing where heat signatures flagged an issue. You can use it to prioritise remedial work and plan future maintenance against actual evidence rather than guesswork.
Multi-site pricing is available for portfolio clients. The survey also sits inside Hawkesworth’s wider electrical maintenance services offer, so it can be booked as part of a coordinated visit covering several compliance items at once.
Book a Thermographic Survey with Hawkesworth
Hawkesworth carries out thermographic surveys across the UK and Ireland, with 190+ qualified engineers covering every region. All engineers are City & Guilds certified and DBS checked.
Surveys are often booked alongside your EICR and PAT testing for a single coordinated visit. Out-of-hours and weekend surveys are available at no extra charge, which matters for sites that can’t pause normal operations. We also track your compliance schedule and send a reminder when the next test is due.
Request a quote and we’ll arrange a survey that works around your building.
Michael Kiddle
Managing Director of Hawkesworth and a nationally recognised leader in electrical and fire safety, Michael (GIFireE) directs one of the UK's leading compliance companies, safeguarding thousands of businesses each year. Through his voluntary Safe Home Initiative, he has identified and removed thousands of dangerous household appliances from vulnerable people's homes, replacing each one with a safe alternative free of charge.
