solar panels - read the threads , still a simplevquestion.

My falt roof hasnt been done at all since it was first put up - at least I do not think it has. I work on the principle if it isnt broke, dont fix it. I had so many other issues I was/am grateful that the flat roof room is dry and doesnt have any issues. I have lived in this house over 25 years and its not been done. I am pretty sure none of my predecessors did it either. It was built in the 1960's ( or possibly early 70's)

If it is a standard flat roof with bitumen felt then it needs to be replaced at least every 20 years or so !, and preferably pro-actively and not waiting until water suddenly starts coming through the ceiling because by then the whole decking will need replacing, plus parts of the ceiling (plus re-plastering etc).

How long have you lived at this property ?.

She claims that the flat roof dates back to the 60's or 70's and has never been recovered. Apart from the strong possibility that it loses more heat than the rest of the roof I don't see how it has lasted this long.

Where bitumenous-felt covered flat roofs are concerned, then you definately DO fix it before it is broke, typically at least every 20 years approx.

Sods law says it starts leaking slowly for some time without any water coming through the ceiling. Then after a long hot summer the autumn rains start with a vengence, (and Cornwall gets very wet) water starts pouring through the ceiling and then you are at the mercy of emergency 'roofers'.

Since this is single story extension, do you have a ladder so that you can get up take a look to see what condition it is in ?. It should be completely flat but with a steady slope towards the edge where the gutter is. Any depressions full of mossy sludge suggests that it has started leaking and the decking is saturated and is collapsing.