Building is 15 years old and i don't remember what is underneath. The only thing that i remember was that rainy water accumulated there all the time before constructing this house and had formed a shape of pond. That time i drained all the water out there and then DPC 4 feet beneath. Foundation was made strong. Another thing i remember is that there was a 4'X4' window which was later on removed from there.
Eh? Can you explain this? Are you saying that before you tiled the walls when it rained it formed a pond on the outside of the tiled wall 4 feet above the DPC?
If it is it's kind of obvious where the cracks come from.