Why terraces fail
A terrace takes the full force of sun and rain. Over the years the waterproofing layer can crack, joints can open and drainage outlets can block. Water then finds its way through the slab into the flats below.
Signs to look for
Check top-floor ceilings for damp patches or stains, and the terrace itself for ponding water, cracked screed, vegetation growth and blocked outlets. Also look at the junction between the parapet and the floor, where many leaks begin.
What to do before the rains
Clear drains, remove debris and note every stain with photos and dates. Book an inspection in dry weather so repairs can cure before the monsoon. A proper assessment will decide whether patch repair or complete re-waterproofing is suitable.
Plan ahead
Waterproofing done in good weather has the best chance to perform. Delaying until leakage appears often leads to interior damage and a larger repair bill.
This article is general guidance. Every building is different, so a site inspection is the best way to decide the right solution.