Building and repairing structures must take into consideration several elements to ensure stability and strength. One of those factors would be waterproofing, and there are different types of waterproofing methods in construction. Application of various waterproofing is dependent on the ground conditions and what the building or structure will be used for. Let’s have a look at the types of waterproofing that exist.
Places where waterproofing is required:
- Basement of structure
- Water tanks
- Swimming pools
Each of these designs or structures has special needs that may change which type of waterproofing is required.
The Different Types of Waterproofing
There are five commonly used waterproofing methods in construction:
- Cementitious Waterproofing
- Bituminous Waterproofing
- Bituminous Coating
- Liquid Waterproofing Membrane
- Polyurethane Liquid Membrane
Perhaps the easiest and most widely known type would be “cementitious waterproofing.” The materials are easy to obtain from masonry product suppliers. Mixing and application is also rather stress-free.
Cementitious waterproofing is considered either a rigid or semi-flexible type of waterproofing. It shouldn’t be exposed to sunlight or other forms of weathering, because it doesn’t go through an expand-and-contract process.
Applications of cementitious waterproofing include:
- Rail and Subway Systems
- Ports & Docks
- Around toilets
- Parking Structures & Lots
- River Locks/Channels
- Concrete Dykes
Bituminous coating is a type of waterproofing that provides a flexible yet protective coat that is altered by formulation and polymerization grade. Flexibility and protection can also be further influenced by fiber reinforcement. The most practical application for bituminous coating would be on asphalt—which is where its second name, “asphalt coating” comes from—and screed wet.
Places with concrete foundations also do well with bituminous coating. However, unless bituminous coating is modified with polyurethane or acrylic based polymers, it cannot withstand prolonged exposure to the sun and will quickly grow brittle.
Bituminous Waterproofing Membrane
A popular selection for low sloping roofs would be bituminous waterproofing membrane. It is self-adhesive and rolls out, making it very simple to apply. The self-adhesive compounds are asphalt, polymers, and various filler. Additionally, resins and oils may be incorporated into the formula to increase the adhesion power.
One thing to look out for is the short shelf life of the bonding properties. Don’t hoard bituminous membrane unless you plan on using it soon.
Another version is “torch on.” These can be exposed or covered, but exposed membrane has a mineral granular aggregate that can withstand the weathering process.
Liquid Waterproofing Membrane
Many places will utilize the liquid membrane method, which consists of a primer coat and then two top coats that are applied by sprayer, roller, or trowel. Liquid membrane waterproofing offers greater flexibility than cementitious waterproofing, as the liquid cures into a rubbery layer on the wall. Another benefit is that the elongation properties of the coating can reach as high as 280%.
Durability, however, greatly depends on the type of polymer the manufacturer is using. For example, many manufacturers mix in polymer-modified asphalt into the spray-on liquid.
Polyurethane Liquid Membrane
Though highly expensive, polyurethane liquid membrane is one of the best for flat roof areas and places exposed to weathering. This form of waterproofing also offers an array of possibilities, because it is flexible enough to easily withstand the normal expansion and contraction of surfaces throughout the year. Polyurethane liquid membrane can also bond to many surfaces, not just concrete and metal.
Special preparations have to be made prior to application. Polyurethane is sensitive to moisture, so all moisture must be drawn from wherever it is being put. Otherwise, peeling and deboning occur over time.
You may not have thought about it, but there are indeed various ways of waterproofing. Each of those methods can also be customized to suit your needs, depending on where the waterproofing is going to be applied. Though some options are more expensive than others, some provide a better investment.