This video shows a massive cold spot behind an electric fuse board. The electrician had left large holes through the wall and insulation, which allowed the free flow of cold air into the hallway.
Closing off the holes and repairing the cavity insulation completely cured the problem, resulting in a much warmer room.
Thermal Imaging service in Fleet, Yateley, Eversley, Hook, Odiham, Crondall, Hartley Wintney, Elvetham Heath, Cove and Church Crookham.