Well......
Back in the day, when i was a 3rd year apprentice i went with my journeyman and a new start apprentice to a boiler change. It was the 2nd day and the customer wanted pipes rerouted under the floor of a cupboard for a new rad. I got sent upstairs to do it with the new lad while my journeyman was fitting the new boiler.
So I set myself up, taking up a couple of boards and fed pipes from both sides to meet under this hatch to be joined.
My boss, being the cheapskate that he was, only ever gave us hairfelt to "insulate" the pipes, so i had pushed this on before i fed the pipes through.
I pulled the felt back and began sweating a coupling on, showing the young lad how it was done
!!!
My journeyman came upstairs asking what I had burned just after I had finished doin the fitting, and I couldnt smell anything as I was choked up with the cold.
Long story short the hairfelt must have caught a spark, ran along the pipe, into the void and up into the attic.
Me and my journeyman dived into the void, it was seriously ablaze by this time, went up really really quickly, and we managed to put it out by stiffling it with the glass wool and the young lad running back and forward to the toilet with buckets of water!!!!
By this time though, the attic was well up and I had to go downstairs and ask the customer to phone the fire brigade.
3 fire engines later it was out. Took abt an hour to put it out.
It was lucky in some respects as the folk had only been in the house for 2 weeks, so they had nothing in the attic eg photos, old irreplacable things, and the guy was so sound about it.
I was absolutly gutted at the time and I couldnt look anyone in the eye, as the woman was crying and my boss was up at the job goin mental, but the guy came over to me, winked, and said " dont worry about it son, i hope my computers f**ked, i was needing a new one anyway"!