A plumbing and heating contractor has been fined after welding sparks set light to roof insulation on a 14-storey apartment development in Staines-upon-Thames, Surrey. Four workers installing an air source heat pump on the roof escaped down a ladder through a single opening as the fire spread across the roof space.
The Health and Safety Executive (HSE) prosecuted C Watkins Plumbing Limited, of Ramsgate, Kent, which controlled the four workers. At Staines Magistrates' Court on 29 October 2026 the company pleaded guilty to breaching Regulation 15(2) of the Construction (Design and Management) Regulations 2015 – the duty on a contractor to plan, manage and monitor construction work so that, so far as is reasonably practicable, it is carried out without risks to health and safety. It was fined £20,000 and ordered to pay £8,270 in costs.
According to HSE, the fire happened on 26 July 2024. Sparks from welding ignited uncovered rigid foam insulation on the roof. HSE found that the company had not planned, managed or monitored the hot works, despite having its own policies requiring this. There was no risk assessment or method statement, no permit to work for the welding, no fire extinguishers, no means of raising the alarm and no second escape route from the roof. HSE inspector Stephanie Hickford-Smith said the company "did not assess the risks and so had no control measures in place."
What this means for you
This case involved a building under construction, so it was prosecuted under construction health and safety law rather than fire safety legislation. But the lesson travels well beyond building sites.
Hot works – welding, brazing, soldering, cutting, grinding and roofing with torches – happen regularly in occupied buildings. Think of roof repairs on a block of flats, plumbing work in a care home, pipework in a school plant room, or the growing number of heat pump and retrofit installations across social housing stock. In those buildings the occupants are still inside, often asleep, and may be elderly, disabled or otherwise vulnerable.
If you are the responsible person under the Regulatory Reform (Fire Safety) Order 2005 – a landlord, housing association, managing agent, care provider, school or employer – contractors working in your premises introduce new fire risks, and you need to know about them and control them. Article 22 of the Order requires responsible persons who share duties for premises to co-operate and co-ordinate their fire safety measures and to inform each other of risks. Article 9(3) requires your fire risk assessment to be reviewed where there has been a significant change, including changes to the premises or the organisation of work. A major programme of works can easily be that kind of change.
In my experience as a fire risk assessor, contractor activity is one of the most common blind spots. The fire risk assessment describes the building as it normally runs, but nobody revisits it when the scaffolding goes up, fire doors are wedged open for access, or a roofer arrives with a gas torch.
Practical checklist before hot works start
- Ask whether hot work is really necessary. Cold-work alternatives (mechanical fixings, push-fit or press-fit fittings, cold-applied roofing systems) remove the risk altogether.
- Insist on a written risk assessment and method statement covering the hot works specifically, not a generic template.
- Use a hot work permit system. Each permit should define the area, time window, precautions, fire watch and sign-off. Make sure someone actually checks it is followed.
- Protect or remove combustibles. Exposed insulation, membranes, timber, waste and stored materials are all fuel. Cover them or move them.
- Provide suitable fire extinguishers at the point of work and make sure operatives know how to use them.
- Keep a fire watch during the work and for a period afterwards – smouldering fires in roof voids and insulation can take time to develop.
- Check means of escape and raising the alarm, especially at height or on roofs. Workers should have a way to raise the alarm and, where possible, more than one escape route.
- Think about the building's own fire safety systems. If detectors are isolated or covered to avoid false alarms, agree compensating measures and reinstate them promptly. Don't let fire doors be propped open or compartmentation breached without control.
- Tell residents or occupants what is happening, especially where vulnerable people may need extra help.
- Review your fire risk assessment where works are significant, and keep records of what you agreed with contractors.
How Obelisk Fire Safety can help
We carry out fire risk assessments for social housing, supported and care schemes, HMOs, schools and NHS premises nationwide, with a focus on the East Midlands and surrounding areas, using BS 9792:2025 for housing and PAS 79-1:2020 for other premises. If you have major works planned, we can review your assessment, advise on controlling contractor fire risks and check that fire doors and compartmentation are still in good order once the works are finished.
Get in touch on 07407 156178 or email info@obeliskfire.co.uk.
This article is for general information and does not constitute legal advice.
Sources
- HSE press release: Aftermath of apartment roof blaze workers 'lucky to escape' from (30 October 2026)
- Construction (Design and Management) Regulations 2015, regulation 15 – legislation.gov.uk
- Regulatory Reform (Fire Safety) Order 2005, article 22 – legislation.gov.uk
- Regulatory Reform (Fire Safety) Order 2005, article 9 – legislation.gov.uk
- HSE: HSG168 Fire safety in construction