18/11/2015
This is the result of a bad installation of a roof water tank (tinaco). This is not a DIY job and do not hire a contractor, that cannot follow basic instructions for proper installation.
This tank was holding almost 1,000 litres, (almost one tonne) of water. and it is lucky there was no one hurt or other damage to the roof structure.
Calling your local home inspector, would have helped avoid this situation, by providing a professional opinion on the overall installation.