Why do you think its a leak Jo?
The cracks in the plasterboard ceiling on the top floor on closer inspection look like they have been filled and repainted in the past (not very well).These cracks in the ceiling boards are in several rooms and there is no apperance of leaking water.
Evening - my house and I are cracking up (literally)
The house was built in the 1970's and I have lived here for the last 18 months.
I've had an outbreak of cracks in the upstairs ceiling which run the length of the roof and clearly follow the platerboards. I also have a number of cracks...