Leaking ceiling or damp wall? A plain guide

Water rarely shows up where it enters. Use this guide to work out where yours is coming from and what to do about it.

1. Where is the damp showing?

• Top-floor ceiling: usually the terrace above. See terrace waterproofing.
• Ceiling or wall below a bathroom or balcony: seepage from the wet area above. See bathroom waterproofing and balcony waterproofing.
• Walls under or near the overhead tank: see water tank waterproofing.
• Basement, lift pit or ground-floor walls: groundwater. See basement waterproofing.

2. When does it show?

• Only after rain: the source is on the outside: terrace, parapet, external wall or balcony.
• After using water upstairs: the source is a wet area or pipe above.
• All the time, even in dry weeks: think of a pipe leak, a tank, or groundwater.

3. What to check before you call

• Are the terrace drain outlets blocked with leaves and plastic?
• Is water standing on the terrace for hours after rain?
• Are there cracks along the parapet or at the wall and floor junction?
• Is the water meter moving when every tap is closed?
• Take dated photos of the stain. Seeing how it changes helps the inspection.

4. What not to do

• Do not just repaint over a damp patch. The stain and peeling will come back.
• Do not pour cement slurry on cracks and call it done. Cracks move and re-open.
• Do not wait for the next monsoon. Damp reaches steel and plaster over time.

Questions