Waterproofing can be define as the formation of internal or external membrane which capable of preventing water from entering or escaping through a permeable layer.there are many different means to provide internal or external membrane i the construction industry.

Internal membrane are provided through waterproofing admixture which are added to concrete during mixing.
External membrane are provided using sheet membrane and liquid coating on concrete surface.
Problem Identification & background 
Many roof through out the world are constructed using poured concrete.these structures are usually made with of reinforced concrete.they are inexpensive but require a great deal of maintenance to keep them from leaking.
The root problem when using concrete as roofing material  is that concrete is porous and retain moisture.Water flows from dampness from Top floor to ground floor through walls.
Leakage from roof top slabs results in:
  • Dampness on wall
  • Wet patches below the slabs leads to staining and discoloration
  • water Dripping
  • Peeling of paint
  • Fungus growth leading to unhygienic condition, ill health and discomfort people living to lower floor
  • Reducing the life of the structure
  • Ingress of water into the wall causes electricity faults 
It is often observed that small plant grow at vertical down take drainage pipe line, resulting in corkage in pipeline, leaking and sweating of pipes and damaging the pipes. 
Due to not concerning the leakage in time moisture  and polluted atmosphere contains sulphate and carbon,  penetrates through the building structure resulting in corrosion of steel.   

Areas of Waterproofing is Needed:
1.    Basement of the building
2.    Kitchen, Toilet and Bathroom
3.    Balcony areas
4.    Roof /Terrace
5.    Swimming Pool
           6.    Water Tank
Type of waterproofing:
Without going in detail here we can take a quick look on type of waterproofing
  1. Cementitious Waterproofing
  2. Liquid waterproofing Membrane
  3. Bituminous Waterproofing
  4. Bituminous coating waterproofing
  5. Bituminous Membrane waterproofing
  6. Polyurethane waterproofing.
Cementitious Waterproofing:- Cementitious products are probably the easiest waterproofing materials to use. They are readily available from suppliers of masonry products, and they are easy to mix and apply. If you plan to use this material, a long-handled brush will make your life easier. Also, spend the extra money to buy acrylic additive (a white, milky liquid) to mix in with the cement product. You will get better bonding and a more solid, durable coating.

The chief disadvantage is that cementitious products have no give to them probably because cement just doesn’t stretch to any degree worth mentioning. They will stand up fine to a head of water, but will tolerate almost no joint or crack movement.
Different Waterproofing Methods & Their Types
Cementious waterproofing

Cementitious waterproofing is used in the following type of structure:
  • Water treatment plant
  • Sewage Treatment plant
  • Bridges
  • Dams
  • Railway and subway system
  • Marine Cargo Ports & Docks
  • River Locks/Channel & concrete Dykes
  • Parking Structure and Lots
  • Tunnel
Liquid Waterproofing membrane:-Liquid Roofing is the process of waterproofing a roof by the application of a specialist liquid roof coating. It is suited to all types of roof, including flat, pitched, and domed. Liquid roofing involves the application of a monolithic, fully bonded, liquid based coating to a roof. The coating cures to form a rubber-like Elastoplast waterproof membrane, capable of stretching and returning to its original shape without damage. Such coating systems are usually reinforced with secondary materials such as glass-reinforced plastic to provide additional tensile strength. The coatings can be applied over most traditional roofing materials, including felt, asphalt, bitumen, and concrete.
The process of liquid roofing provides a cost-effective method of making a new or existing roof waterproof. It can deliver up to 25 years performance depending on the coating system employed. It is estimated that liquid roofing is 70% less expensive than overall roof replacement in refurbishment situations.
Bituminous Waterproofing:-Bituminous waterproofing systems are designed to protect residential and commercial buildings. Bitumen (asphalt or coal-tar pitch) is a mixed substance made up of organic liquids that are highly sticky, viscous, and waterproof. These systems are sometimes used to construct roofs, in the form of roofing felt or roll roofing products.
Different Waterproofing Methods & Their Types
Bitumen application
Bituminous Coating Waterproofing Method:-Bituminous coating is a type of coating used for waterproofing and flexible protective coating. It is an excellent protective coating and waterproofing agent, especially on surfaces such as concrete foundations.
Different Waterproofing Methods & Their Types
Membrane waterproofing

Bituminous Membrane Waterproofing Method:-Bituminous membrane waterproofing is a popular method used for low-sloped roofs due to their proven performance.
Polyurethane Waterproofing:-Polyurethane is made up of two components, base and reactor. Polyol acts as the base, while isocyanide is the reactor component. The combination of both these in a specific design ratio creates a liquid coating for waterproofing applications. Polyurethane is a rather popular choice due to its ease of installation. Unlike other waterproofing systems like sheet membranes and liquid applied membranes, this polyurethane application requires comparatively less skill and supervision. Application is fast and this type of treatment can be used for post construction applications as well.
It is easy to install, provides seamless finish and have a long term durability and wear resistant. It is UV and weather resistant alkaline cleaners, battery acid and fuels.