Terrace leakage

Inspite of repeated reminders to the society the terrace repairs are not been done.the structural audit clearly mentioned that the terrace needed immediate attention and that it should be repaired with brickbat and cobalt but instead the society Apple’s cheap waterproofing and is washed out on the first day of monsoon. The other three flat owners are not interested in getting the society repair the building as they do not want to be in bad books. I would like to know 1. If the society is not repairing the terrace can I repair only my portion (there may still be leakage as water finds his Way) and claim the amount for. Society 2 if the soc does not pay the expenses to the contractor or to me can I give the Soc a notice mentioning that I will repair at my cost and will recover the amount by not paying my maintenance bills. Is it legal. Or will I be a defaulter 3- if I cannot recover trough maintenance ten how can I recover the amount and how long will it take And Cani add other expenses like legal prof fees mental torture and loss of interest