15 Reasons for water dampness

There are various causes of ingress of moisture in walls that make them damp:

1. Defective roof leakage is a major source of water entering the wall and making it damp.
2. Porous bricks used in construction is a permanent source of dampness in walls as they attract moisture.
3. Bad materials used in construction are also a source of damp walls.
4. Vegetation – Growth of vegetation in the wall indicates the presence of moisture or water without which it could not grow. Vegetation develops further cracks in a wall already having cracks and cause soakage in the wall.
5. Earth backing against the wall – Dumping of earth against the wall causes dampness in it.

6. Cavities, holes left in the wall due to negligence and dab-holes kept for the erection of scaffolding and later not filled properly with concrete are a prospective source of attracting and storing moisture.

7. Mortar joints not laid properly and uniformly are sources of attracting moisture.
8. The worst source of moisture ingress in building walls is the defective damp proof course. Decayed, dilapidated or defectively laid damp proof course, i.e., failure of the damp proof course to arrest rising of moisture from below causes dampness in wall.
9. Earth banks – Construction of earthen bank by the side of a building, side slope covering some height of the wall above damp proof course would cause dampness in wall.
10. Splashing of rain off the ground on the wall above the damp proof course happens when the plinth height is low or there be ground nearby with a higher level.
11. Defective window sills allow stagnation of water on them.
12. Sloping ground – This generally happens in hill areas, where buildings are constructed on the slopes of the hills.
13. Dampness in hollow walls is caused due to deposit of mortar droppings during construction and lack of ventilation.
14. Leaking pipes – Soil, wastewater, rainwater, or water supply pipes allow water to enter the walls.
15. Salt in the plaster – The presence of salt in the plaster or precisely in the sand used for plaster will render the wall damp.