r.rain wrote:
Weird thing happened today, I came back from work and found globs of
rainwater in my dining room and in my lounge on the floors. This is the
first time I have ever experienced this in 2 years and it looks as
though water had been coming down the chimney after a heavy downpour
this afternoon. Should this happen, should there be something ontop of
the chimney to stop water ingress?

If the chimney isn't used, yes. If it is used, have a fire
every so often to dry it out.