structural repairs and tenants rights

Our block has a problem with waterproofing. Two apartments have water leaking into other apartments. In one instance the tenant in the apartment where the water is leaking from have told the Body Corporate they cannot be without access to their shower for the length of time it takes the waterproofing to set (72 hours). The water is leaking through a concrete floor into the apartment below and presumably also spreading horizontally undermining the structural integrity of the building and potentially creating damp problems for adjoining apartments. In the other instance the leaking is due to a dodgy reno in the bathroom and needs more extensive work. Again the tenants are reluctant to have the work done due to the inconvenience. The ceiling in the apartment below has water and rust damage. The Body Corporate seems to be caving in to the obdurate tenants at the expense of other residents. I would be grateful if anyone knows what action the Body Corporate can/should be taking. In the instance of the dodgy reno who should pay.