OK so they removed a door chime to plaster a wall.
No big deal, however they did not know that it was powered by a mains powered transformer that was under insulation.
No attempt was made to isolate the bell wires and IMHO for the last two days the bell wires have been touching resulting in the transformer overheating and causing a small fire that took out several T&E lighting cables before the MCB tripped.
The yellowish insulation is the old stuff, the 300mm new brown stuff was placed over the old stuff back in November.
Lucky bastards looking at the scorch marks on that timbers.
One other point/question. The insulation has turned white where the most heat was. Any ideas why?