Today, inspired by Waynes 'Just do it' enthusiasm, I stripped tiles out of the out-house roof and used them to close the hole.
This is how Wayne and I left the hole in case it rained.
Wayne and I had already cut wood into strips and re battened the chimney hole.
So all I had to do was put the tiles in, it is kind of like a game of Tetris getting them to fit.
I then retiled the outhouse where I had scavenged the tiles from, I used tiles but the only problem was they were carpet tiles :-) The back of them does seem to be very waterproof. I am thinking of sending the picture to the tiles manufacturer and asking them if I have installed them correctly!