Waterproofing

Weatherproofing a building includes.

• Waterproofing of roofs.
• Waterproofing of terraces.
•  Waterproofing of balconies.
• Waterproofing of kitchens.
• Waterproofing of wet areas.
• Waterproofing of bathrooms.
• Waterproofing of toilets.
• Waterproofing of water tanks.
• Waterproofing of swimming pools.
• Waterproofing of foundations.
• Waterproofing of basements.
• Waterproofing of side walls.
• Sealing of window frame edges.
• Cracks repair and prevention.

Waterproofing coatings must be selected depending on which side the waterproofing has to be done. Both in new or remedial waterproofing, there could be both Negative and Positive sides of the application. As discussed earlier, Positive side waterproofing implies that the waterproofing must be done from the side from where water ingress is possible. Side which is directly exposed to water and hydrostatic pressure. Negative side waterproofing implies to the opposite side of hydrostatic pressure. 

It is always advisable to take up waterproofing treatment from outside- Positive side of the structure if it’s possible. Majority of the products available with the manufacturers worldwide are for this type of waterproofing. Negative side products are limited to cementitious systems. The use of Concrete Admixtures is always suggested to make the structure watertight. 

The most disadvantage of negative side waterproofing is that the water will enter the concrete structure and promote corrosion and deterioration of reinforcing steel if chlorides are present. Positive side waterproofing prevents ingress of water into the concrete substrate and does not allow corrosion.

Waterproofing Repairs are required in the buildings which were not waterproofed earlier or were not waterproofed properly, buildings under renovation or very old buildings.

Waterproofing Repairs are required in the buildings which were not waterproofed earlier or were not waterproofed properly, buildings under renovation or very old buildings. You would know that your house requires waterproofing repairs if there is”

 • Peeling Paint: One of the most common causes of peeling paint is high humidity. When your basement has a dampness problem, moisture wicks through the porous surface of the paint and is absorbed into the brickwork behind it. When temperatures become warmer, the moisture behind the paint turns into steam and forces the paint off from behind.  

 • Cracks in walls or floor: Cracks can form in any shapes, sizes and directions and they don’t usually appear naturally. You might find vertical cracks, or horizontal cracks. It can be from settling of the foundation, pressure on the walls or under the floor, or many other factors. Damp spots on the walls or ceilings: Moisture or leakage can cause dampness on the walls. On an unpainted wall that holds excessive moisture, it will turn dark gray. A painted wall will show darkening of the paint, or discoloration.  

 • Unpleasant Odor: Decaying unpleasant odors are given off by the decaying material associated with mold or mildew. As soon as you enter a room or a basement which has seepages, an unpleasant odor of decay hits you. You can try to take out the smell by locating the source and cleaning the items associate with it.  

 • Mold & Mildew: Excessive moisture in your basement can cause mold and mildew. These living organisms can grow and multiply in the walls, on or under the carpet and furniture. Black, brown, yellow or green, mold and mildew can cause severe health problems, including headaches, water eyes, coughing, scratchy throat, and blood in lungs. Mold is harmful to us and its symptoms are different depending on the person. Mold does affect our immune system and can cause health problems, in some cases, severely threatening problems. Common symptoms consistent with mold are allergic reactions, nausea, headaches, respiratory illness, itchiness and more. The elderly and infants are at higher risks of developing these and other health problems.  

 • Exposed & Rusting steel reinforcements: Metal is prone to rusting when there is excessive humidity. The water seepage causes cracks and debonding in RCC slabs, Beams and Columns. The steels reinforcements get exposed and gets rusted due to oxidation. You will need to remove the rust, treat with anti-rust treatment, maybe reinforce and repair the damage with Micro Concrete, Repair Mortar or other suitable treatments and repaint the damaged area as soon as possible, and then eliminate the cause of the moisture, otherwise the rust will reappear.

Polyurethane waterproofing products are excellent materials for waterproofing, which is an absolute must during most construction processes.

Polyurethane waterproofing products protect buildings from water and humidity and provide excellent UV resistance.

GENERAL INFORMATION ABOUT POLYURETHANE WATERPROOFING

Waterproof polyurethane is a popular option for waterproofing applications because it can be applied relatively quickly and easily. Additionally, you can use polyurethane waterproofing products during and after construction. Common applications include roofs, balconies, terraces, kitchens, basements, patios, and wet areas.

The advantages of polyurethane waterproofing are clear: in addition to fast and easy application, it features a seamless finishand and offers durability as well as resistance to UV, water, weather conditions, and many chemicals.

Cementitious materials are excellent products to be applied on below grade structures, both positive and negative sides. These systems are based on a mix of Portland Cement with or without sand and an active waterproofing agent. There are two types of cementitious systems: Crystalline System, Acrylic Modified Systems. These are applied using brush or trowel to the concrete or masonry surfaces and become integral part of the structure.

In the under-construction buildings, the biggest benefit of using a Cementitious system is that it does not need a dry surface. In fact, some moisture in the structure helps the system and improve its efficacy. It can also be applied if the concrete is not fully cured. These systems can be applied to both the walls and floor

All cementitious systems have similar application method. The performance may differ from product to product depending upon its formulation. The Cementitious systems lack crack bridging or elastomeric properties but have great adhesion to the substrate.

Advantages of Cementitious Systems:

 • Positive or Negative Side application

 • Remedial/ Repair Application

Disadvantage of Cementitious Systems:

 • No Movement Capability

 • Site Mixing Required

 • Can Not be used in high traffic areas

Acrylic modified cementitious or Polymer Modified Coatings are on the site blended coatings. These are mix of a factory blended mix of Portland Cement & Sand (may or may not be blended with special fibers) and Acrylic Emulsions. These acrylic emulsions add waterproofing characteristics to the system. These systems can be applied with brush or trowel. These can also be applied with a reinforcement mesh. The mesh adds some crack bridging capabilities. Many manufacturers are offering premix special fibers in the powder component. Different manufacturers offer product with Powder: Polymer ratio from 1: 0.2 to 1: 0.5. Higher the Polymer ration, better would be elongation and crack bridging ability. 

Acrylic Modified coating are applied in a thickness of 1.0mm to 2.0 mm. However, in certain application, using a trowel these can be applied up to 4-5mm thickness too. It is highly recommended to apply protection layer. Curing is recommended for 24 hours.

External Membranes are Sheet or Pre-Formed membrane systems are reliable and durable waterproofing solution that can fulfill the requirements of even the most severe and demanding below ground structures. These are popular choice as these can withstand elevated level of ground water pressure, aggressive chemicals present in soil or water, dynamic forces due to earthquakes and ground settlements.

The sheet membranes come in fixed and controlled thicknesses, widths, and lengths. These range in thicknesses ranging between 1mm to 5mm and widths ranging between 1.0 mtr to 3.0 mtr. 

Application of Pre-Formed Membranes, in the basement requires protection during backfilling, Steel Binding and Concrete Pouring. Some manufacturers, in the recent years have started offering products for below the raft application, which they claim to not need any protection from Steel Binding and Concrete Pouring. Unlike Liquid Applied Membranes, Preformed Membranes have multiple joints and are not seamless. These are also not self-flashing at protrusions and junctions. Same is the case at the termination pr transition into another section of the building envelope. Being too heavy these are limited for application on the horizontal surfaces. Vertical single ply membranes are more difficult to apply then the Liquid Applied membranes. It is difficult to handle and joining the materials. The seams are lapped and sealed for complete waterproofing, particularly in small areas such as planters.

Different Types of Membranes are.

 • APP: The APP membrane, short for Atactic Polypropylene Membrane, is a special waterproofing material that is manufactured from Bitumen. APP membranes comes in rolls, measuring 10 mtr x 1mtr. With proper workmanship, the APP membrane is a very efficient and durable waterproofing material used in most constructions. It is a common material sed on concrete flat roofs. These are also used for waterproofing of concrete gutters, basements and retaining walls.

 • SBS: The SBS Membrane is a bituminous waterproofing membrane manufactured by blending a mixture of bitumen and SBS (Styrene Butadiene Styrene) polymers to obtain excellent waterproofing and low temperature flexibility properties. The polymerized bitumen is coated onto a dimensionally stable reinforcement core of non-woven spun bond polyester rot-proof fabric. The membrane has excellent tensile & tear strengths and is highly resistant to puncture. It is flexible and is suitable for applications where high structural movement is expected.

 • HDPE: HDPE Membranes are based on high-density polyethylene material, designed to provide water and water vapor protection to water excluding structures, securing concrete from aggressive ground salts and chemicals related corrosion.

 • TPO: Thermoplastic Polyolefin Membranes are single-ply roofing membranes that are one of the fastest-growing commercial roofing systems on the market. TPO roofing systems are made up of a single layer of synthetics and reinforcing scrim that can be used to cover flat roofs. TPO membranes are manufactured in sheets that are 10, 12, or 20 feet wide. These sheets are then rolled up and taken to the commercial facility. TPO has gained industry acceptance with the natural reflective surface to reflect UV rays. These are generally used in large Industrial and Commercial segments.

 • EPDM Rubber: EPDM is an extremely durable synthetic rubber roofing membrane (ethylene propylene diene terpolymer) used in various low-slope buildings and basements worldwide. Its two primary ingredients, ethylene, and propylene are derived from oil and natural gas.

 • Composite Plastic: Composite Plastic membranes bring sustainability to the construction industry, using recycled plastic. Anchor Grip Composite Plastic Membranes are plastic sheets with closely spaced L-Shaped locking extensions called Anchor Grips. These are best suitable for Basements and Retaining Walls.

• Non-Bituminous Composite Membrane: is a membrane developed for internal and external waterproofing where a covering must be applied in areas like kitchen, toilets etc. where water ingress is expected. It consists of Bituminous compound reinforced and protected on both sides with Non-Woven Propylene. These are thin and flexible and are compatible with all cement screeds.

Several types of Joint Tapes are needed in construction industry. These are used to seal the joints between two substrates, Vertical and Horizontal Joints, Expansion Joints, Construction joints and cracks, Future movements of the construction without causing damages, Basements, Tunnel construction, Around metal surfaces, Swimming pools, Cable and pipe penetrations, Sewage treatment plants.