Well I turned up at 9am, apparently the builders cant make it today so we are meeting over the weekend (hopefully)
Anyway why i was there i drilled a hole in the crack across the conservatory, and found it to be on a joint, which is on a joist.
Then I put another hole a few inches away, and put a interscope though and had a look.
The joists dont seem to be very big, and they are braced but there is not any support along it, as the builders said they had done.
I didn't do anything with the other 2 cracks yet as the customer dont want holes everywhere, at the moment. I cant see the next crack being on a joint, as its 1.9m away, and only goes though 2 tiles, as does the 3rd crack, which comes off a wall, and is on the line of the old wall.
They have spoke to a legal advisor on this, and have been told that both parties me and the builder are liable, them for not doing the work properly, and me for tiling on a unsuitable substait.
I am certain there was not any movement when I tiled, could it have started to move, for any reason since work was completed.
I will let you know how the meeting with the builder goes, when it actually happens.