Why live in roof top and expect the water proofing last. Do you think that will last long enough to maitain your daily living standard.
May be you can consdier painting some form of sealants to your area affected.
However you better ask for specialist advices on how much does it cost per square feet the number of years of written guarrentee of waterproofing. Remember finding the source of leaking is crucial to the success of water proofing. Other builders work and insurance cost have to be considered.
Best wsihes
Yeung
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