Johannesburg – A contractor’s negligence resulted in the collapse of a roof at the Charlotte Maxeke Johannesburg Academic Hospital, the Gauteng infrastructure department said on Wednesday.The contractor's workers piled stones on the roof over the entrance foyer during waterproofing work, MEC Jacob Mamabolo told reporters.The weight caused the roof to collapse on March 2. Five people sustained minor injuries.Mamabolo was reading from a report dated April 4, which was compiled by specialist attorneys Adams & Adams. He said the contractor should have known that the roof would not support that much weight.He said the department had started a legal process to hold the contractor accountable.“We think that they will challenge the fact that we are placing the liability on their doorstep. Yes, we are placing the blame squarely on the door of the contractor who was doing the waterproofing work at the hospital.”The labour department had issued a notice of termination to the contractor. It was not allowed back on the site and a new service provider had been appointed.The department was determining which other projects the contractor was working on.“We will not hesitate to take action against contractors. We will act without fear or favour where we find that contractors are not complying or not toeing the line with their contractual obligations.“When we pay the invoices, we expect value for money. This is not for us as government, it is for South Africans."Construction sites were not being managed properly and standards were not being enforced. A “constructions site management toolkit” would be made available when he delivered his budget vote later this month, Mamabolo said.