Water seepage in buildings is generally caused by defective fabric or installations of buildings and the lack of proper maintenance. This may be manifested as follows -

1. Leakage in the drainage pipes of the upper, adjacent or your own flat
2. Leakage in the water supply pipes of the upper, adjacent or your own flat
3. Defective or deteriorated waterproofing of floor slabs or bath-tub seals
4. Seepage of waste water or rain water through roof / podium / balcony / external wall / window of buildings

In most cases, water seepage is caused by leakage from defective water pipes, sanitary fitments or drainage pipes. Usually, these defects can be rectified by simple repair works. Owners should hire a building technician or licensed plumber to identify the cause of seepage, and arrange for prompt repairs. The investigation methods are explained in this "Do-it-yourself Water Seepage Test" pamphlet:
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