What is waterproofing and why is it necessary?

Waterproofing is a process that protects your home from water damage. Protecting your property against water damage can be done in various ways, but the most popular and effective way is with a liquid sealant on the exterior surface of the building. This liquid sealant blocks moisture from coming into contact with walls or foundations. The liquid also prevents any leaks from spreading inside the house and causing mold to grow as a result of high humidity levels. When you waterproof your home, it will be able to resist all kinds of weather conditions such as heavy rainstorms, storms, hail, sleet or snow that may cause leakage through cracks or joints in walls and roofs etc.

Types of waterproofing methods

There are a number of methods for waterproofing, the most common being the following:

Bituminous Water-Proofing refers to a material that is mixed with bitumen and used as a water proofer. Bituminous materials have been around since man learned to use fire. In fact one of its first uses was as a mortar in stone structures.

The following are the most common bituminous materials used in construction:

1) Tar paper (also sometimes called felt paper) is a good water proofing material when it has not been exposed to standing water. It does however absorb moisture if it is left in soil for long periods of time and therefore should only be used in temporary applications.

2) Built-up roofing is a composite material made from two layers of felts and bitumen which is laid in hot asphalt and squeegeed off to make a thin, waterproof coating. It is used when it will be applied on slopes greater than 1/4 inch per foot (1:40), but not in standing water.

3) Coal-Tar felt is applied in much the same way as #2 except it is made from waste material, which would otherwise be discarded. It has a life expectancy of 20 years if properly maintained.

4) Modified Bitumen sheeting is asphalt rolled out flat with the addition of mineral fillers to give the product strength. It is used as a roofing material on roofs, water towers and tanks as well as for some flat deck waterproofing projects.

5) Butyl rubber sheeting is an alternative to #4 except it has a life expectancy of 15 years because of the addition of polymers during manufacture which cause it to have a resistance to oxidizing.

Bituminous membrane refers to a type of waterproofing that has the adhesive applied to one side which adheres it directly to another surface such as a wall, roof or floor. There are two types of bituminous membranes: natural and synthetic. Natural membranes include asphalt impregnated felt, coal-tar felt, asphalt impregnated paper and lead. Synthetic membranes include butyl rubber sheeting and urethane. Membranes are manufactured in various widths depending on the thickness of the material which ranges from 1/4 inch to 6 inches.

Bituminous coating refers to a type of waterproofing that consists of an application of bitumen and various fillers, such as sand and pulverized coal, to a surface. The material is applied in two coats: the first coat is allowed to cure for 2 hours before the second coat is applied. Bitumen paint comes in three forms:

1) Asphalt paint which can be used on wood, metal or concrete surfaces.

2) Coal tar paint which is applied to masonry surfaces and found on some sidewalks.

3) Asphalt impregnated paint which is only used for painting concrete.

Polyurethane Liquid Membrane refers to a type of waterproofing that consists of two components: a base material and a catalyst which actually makes the coating liquid. The two parts are mixed together and applied to a substrate where they cure into a tough, elastic waterproof membrane. It is not affected by exposure to ultraviolet light nor does it oxidize when exposed to air.

Cementitious Waterproofing refers to one of the oldest methods for waterproofing dating back before the Romans used mortar made from lime and sand which was designed to be water resistant. It consists of a chemical reaction in which cement particles aggregate together forming a thin membrane.

Liquid Waterproofing Membrane refers to a type of waterproofing that is used when the substrate is small or flat, such as an individual pipe joint, and has no access for covering it with another material. The material is applied in two coats: the first coat is allowed to dry before applying the second coat. The second coat is usually thicker than the first, which produces a durable waterproofed surface.

Types of Waterproofing

Primarily used for: Temporary applications and preventing water from entering a structure through the roof.

• Bituminous Sheet Waterproofing

Coal-Tar Felt

Asphalt Impregnated Paper

Asphalt Painted or Coated Surfaces

Butyl Rubber Sheeting

Polyurethane Liquid Membrane

Cementitious Waterproofing

Liquid Waterproofing Membrane

Temporary applications and preventing water from entering a structure through the roof.

• Bituminous Membrane

Bitumen Paint- Asphalt Paint, Coal Tar paint, Asphalt Impregnated Paint

Butyl Rubber Sheeting

Polyurethane Liquid Membrane

Cementitious Waterproofing