An incident occurred in a pullover manufacturing plant during the installation of heat-applied aluminium protective strips on the firewalls. In the angle formed by the firewall and the roof’s edge cladding, on the side of a row of poplar trees, a small amount of dry leaves hidden in the double skin of the cladding started to burn, causing a strong smoke release due to the flames. The problem was detected and the fire quickly extinguished using resources deployed on the roof, in accordance with the issued hot works permits. Meanwhile, smoke entered the building and the fire detection system was activated, causing the fire doors to close in the zone of the alarm. The security detail called the fire department and the site was evacuated. The emergency services arrived a few minutes after the start of the fire with the following equipment: light vehicles, two fire trucks and an aerial ladder. Equipment was positioned on the fire service access road but did not have to be used. The inspection carried out by fire-fighters concluded the absence of risk of fire restarting following the measures taken upon their arrival. The impact was minimal. However, following this incident, a procedure was to be set up to prepare a document for all hot works within 1 metre of the double-skin cladding on the side of the row of poplar trees. It would become mandatory, in this case, to proceed with removal of the inner face of cladding to ensure the absence of any risk; moreover, a rigid fireproof screen was to be placed between the edge cladding and plant technician in order to protect against direct flames.