Roof Fire During Welding On 14 Storey Apartment Block

Brief Summary

While fitting an air source heat pump on the roof of a 14 storey apartment block, welding sparks ignited exposed rigid foam insulation and caused a rapid self sustaining fire. An employer failed to plan manage and monitor hot work, with no risk assessment method statement permit fire extinguishers or means of raising the alarm. The case shows the consequences of not applying basic hot work controls and emergency arrangements on construction sites.

What Was The Incident?

On 26 July 2024 four subcontractors were installing an air source heat pump on the roof of a building under construction when welding sparks ignited uncovered rigid foam insulation. The fire developed quickly and spread across the roof before burning out when it ran out of fuel. The men escaped through a single opening in the floor and down a ladder to level 14. There was no other route off the roof no means of raising the alarm and no fire extinguishers. An investigation found the employer had not prepared a risk assessment or method statement and had not issued a permit for the welding work.

What Was The Outcome?

The employer pleaded guilty to breaching Regulation 15(2) of the Construction (Design and Management) Regulations 2015. The company was fined £20,000 and ordered to pay £8,270 in costs on 29 October 2026.

Key Points To Consider

Plan and permit hot work. Review risk assessments method statements and the permit to work system so a permit is issued and signed off before any welding or other hot work begins and so controls are checked while work is under way.

Control combustible materials and ignition sources. Remove or protect exposed insulation and other combustibles around the work area and assign a fire watch where removal is not possible; check that sparks cannot reach fuel sources before work starts and during hot work.

Provide escape routes alarm methods and extinguishing equipment. Confirm there are adequate escape routes or a clear evacuation plan means to raise the alarm and accessible fire extinguishers on site and train workers in their use and in emergency procedures.

HSE Prosecution Link