The fire service has also issued a warning to businesses, stating the photos show how important fire doors were to preventing further damage.
Nottinghamshire County Council’s West Bridgford headquarters caught fire on Thursday, July 28 when an electrical fault in the ceiling void sparked and set alight.
Council workers and councillors were evacuated from the building and 12 crews from Nottinghamshire, Derbyshire and Leicestershire fire services were sent tackle the blaze.
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The flames led to the first-floor office of Coun Neil Clarke (Con), portfolio holder for transport and environment, being ‘pretty much burnt out’, with Coun Clarke losing personal items, files and computers.
More than 20 hours of fire investigations deemed the cause of the blaze as accidental, although the fire service has said the incident could have been ‘much worse’ had it not been for fire doors installed in the building.
The fire service says automatic, self-closing fire doors shut when alarms sounded, meaning damage to the building was significantly reduced.
The blaze did, however, spread to the second, third and fourth floors, with County Hall impacted by fire, smoke and water damage.
A fire service spokesperson said: “Photos from the County Hall fire show the importance of fire doors.
“The fire was contained to one corridor by self-closing fire doors which shut when alarms sounded.
“Damage to the building could have been much worse if these weren’t in place.”
Tim Marston, watch manager, added: “The fact that the affected floor had well-fitting automatic fire doors, that functioned correctly, is a testimony as to why the most severe fire and radiated heat damage was contained to one area, leaving adjacent stairwells clear to aid evacuation.
“I urge all building owners, where fire doors are fitted, to ensure they check the effectiveness of any automatic or self-closing devices, that doors fit correctly within the doorframe and escape routes are always kept clear.”
County Hall was handed back to the council on Monday, August 1 with a clean-up operation underway.
Council staff continue to be asked to either work from home or from alternative buildings while this work takes place.
And the ruling Conservative group is expected to face disruption, with councillors to be rehoused into alternative accommodation until repair work concludes.
Coun Ben Bradley MP (Con), council leader, said: “In case anyone was in any doubt about the fire at County Hall last week, these pictures show the view from my, now obviously uninhabited, office.
“The fire service has confirmed the fire was caused by an electrical fault.
"Thankfully, nobody was in the room at the time.
“I’m very grateful to staff and emergency services who ensured everyone left the building safely and things were brought back under control quickly.
“I don’t think we’re getting back on this corridor any time soon.”