Firefighters have been at an office in Preston after a fire broke out.
A wall heater in the ground floor of the premises in Tulketh Brow, Ashton-on-Ribble, set fire to floorboards.
Two fire crews from Preston responded around 11.36am and firefighters used a portable saw to cut away smouldering floodboards.
A thermal imaging camera identified any burning residue which was otherwise out of sight.
A fire service spokesman confirmed no one was injured.