Andy Hall wrote:

The roof tiles have lots of moss
growing on them as well.


That's no real issue and can easily be removed. I quite like to see
a certain amount of lichens on roof tiles. It makes them look more
interesting.....

I've been wondering about that - this year, I noticed a few small clumps of
emerald green moss here and there on my roof. Is it likely to do any
damage? If so, what sort of damage? An uncle who saw it, insisted it
needed to be removed immediately, as it would damage the roof.

Sheila