This document discusses various methods of damp proofing buildings to prevent moisture leakage. It describes common causes of dampness like rain, ground moisture, and condensation. Effects of dampness include damage to walls, electrical issues, and health problems. Methods of damp proofing discussed are using a damp proof course, integral damp proofing of concrete, surface treatments, cavity wall construction, guniting, and pressure grouting. Common materials used for damp proofing are bitumen, mastic asphalt, bituminous asphalt, metal sheets, cement concrete and plastic sheets. Foundations can be protected from ground water using foundation drains, damp proof courses, raft slabs, and asphalt tanking.

1. Presented by :
Irshad Ansari
( CONSTRUCTION TECHNOLOGY )
DAMP PROOFING

2. IT IS A
TREATMENT
OF SURFACE
OR
STRUCTURE
IN A
BUILDING
TO PREVENT
LEAKAGE.
DAMP PROOFING

3. CAUSES OF DAMPNESS
1. RAIN PENETRATION :
It takes place through the joints, roof components and porous
bricks or stones

4. 2. GROUND MOISTURE
Clayey soil retains moisture causes dampness due to
capillary rise.

5. 3. CONDENSATION
Condensation of moisture present in the atmosphere under very cold climate
causes dampness on the ceiling walls, floors.

6. 4. POOR DRAINAGE AT SITE :

7. • Dampness gives rise to breeding of mosquitoes & create unhealthy
conditions.
• It may causes softening & crumling of plasters.
• Wall decoration & paint is damaged.
• Moisture causes rusting & corrosion of metal fittings.
• Dampness breeds germs of disease like tuberculosis, neuralgia.
• Dampness promotes & accelerated growth of termites.
• Timber fittings such as doors, windows etc. coming in contact with damp
walls get damaged because of warping etc.
• Electrical fittings get damaged, giving rise to leakage of electricity & danger
of short circuiting.
• Floor coverings get damaged.
EFFECTS OF DAMPNESS

8. METHODS OF DAMP PROOFING
1. Use of damp proofing course (DPC) :
membrane damp proofing
2. Integral damp proofing
3. Surface treatment
4. Cavity wall construction
5. Guniting
6. Pressure grouting

9. 1. Use of Damp Proofing Course ( DPC) : Membrane
Damp Proofing
These are the layers of water repellent materials such as bituminous, mastic asphalt,
plastic sheets, cement concrete, metal sheets, mortar etc.

10. 2. Integral damp Proofing :
The integral treatment consists of adding certain water proofing compounds
(chalk, talc, silicates, publo, permo, silika etc.)of materials to the concrete
mix, so it becomes impermeable.

11. • The surface treatment consists of application of layer of water repellent
substances on the surface through which moisture enters.
• It is only successful when moisture is superficial, i.e. not under much
pressure.
3. Surface Treatment :
Distempering Plastering

12. 4.Cavity Wall Construction :
In this main wall is shielded by an outer skin wall, leaving a cavity
between the two.

13. 5. Guniting :
This consists of depositing layer of rich cement mortar(1 cement : 3 sand or
fine mix) by pressure (2 to 3 Kg/cm2) to the exposed surface of wall

14. • In this method, cement
grout is filled in cracks,
voids in the structure of
building by pressure.
• This method is effective to
control entry of gound water
through foundations.
6. Pressure Grouting :

15. MATERIALS FOR DAMP PROOFING
1. Hot Bitumin 2. Mastic Asphalt

16. 3. Bituminous asphalt 4. Metal sheets

17. 5. Cement Concrete 6. Plastic Sheets

18. • Foundation may receive water percolating from adjacent ground and this
moisture may rise in walls.
• This can be checked by providing air drain parallel to the external wall.
• RCC cover is provided.
• Opening and gratings are provided at regular interval for passage of air.
• Usual DPC are also provided horizontally & vertically.
DPC TREATMENT IN BUILDING
1. Treatment to foundations against gravitational water

19. • Provision of foundation drains &
DPC.
• Provision of RCC raft & wall slab.
• Asphalt tanking.
2. Treatment for basements
When basement in dump soils are constructed, following
methods are followed :

20. THANKS