One of the most critical elements that decide the life of any structure is the quality and extent of its waterproofing. Though a waterproofing system typically amounts to less than 1% of the total construction cost, it plays a critical role in ensuring the quality and longevity of the structure. Poor focus on waterproofing of a structure can significantly undermine the expenditure incurred on every other aspect of the building.

The role played by below-grade waterproofing is even more critical due to the complex infrastructure of modern cities, the time and disruption caused by maintenance and repair far supersede the cost involved in applying below-grade waterproofing. Because of such challenges, it becomes more significant when compared with above-grade, and also because they are exposed to the withering forces of water and corrosion for prolonged periods and with greater intensity.

Below-grade waterproofing systems are popularly used in the public infrastructure and construction sector for structures, such as basement slabs, foundations walls, planters, tunnels, bridges, sidewalk vaults, elevator pits, plaza decks, split slabs, sub-structures, and drainage systems. They are an integral part of almost every structure.

The global waterproofing market was estimated at around US$ 8.0 billion in 2019, and out of which below-grade waterproofing accounted for a 15% share. The share is expected to increase as more complex structures are the need of the day.

Diving Deeper into the Below-Grade Waterproofing Market

The touchstone of excellent below-grade waterproofing material is the set of qualities such as- uniform thickness, flexibility, being able to resist the constant hydrostatic pressure, chemical erosion, especially under high groundwater conditions and have a low absorption rate to protect the structures. It is through membranes, that below-grade waterproofing is done. They are subsumed under two categories- Sheet-Based Membrane and Liquid-Coated Membrane.

• Material: Sheet-based membranes are made of Polymers, Bentonite, and Rubberized Asphalt. Liquid-coated membranes, on the other hand, are made using Bitumen and Cementitious materials.
• Market Share: Sheet-Based Membranes are more popular with around two-thirds of the share owing to properties like robustness, self-reinforcement, and controlled thickness; there is no need for mixing or specialized equipment either.
• Growth: Increasing usage of breathable waterproofing membranes and environmentally safe materials are driving the growth of sheet-based below-grade waterproofing market.

The selection of the type of sheet and its materials depends on a wide array of factors such as site and soil conditions, water table information, service life, total cost of ownership, and the construction process.

Here is a quick material-based analysis:

There are four ways in which below-grade waterproofing can be applied and they are:

• Fluid-Applied: Covered around less than half of the market in 2019, due to high affordability and use of Bitumen. There are three ways in which fluid-application is done: Spray-Applied, Cold-Applied, and Hot-Applied.

• Self-Adhered: Impressive growth of this segment is due to the qualities like controlled thickness, excellent reliability, excellent chemical resistance, no VOCs, and high crack coverage.
• Fully bonded: Highly suitable for basement waterproofing as they come in 1-2 meter wide rolls and bond with concrete to prevent lateral water underflow and migration.
• Loose-laid: Are easy to install and are economical.

The Steady and Impressive Growth Dynamics

The COVID-19 crisis has upended every industry, without exception. But our estimates foretell a sanguine picture of growth which is expected to rebound in 2021, after a period of growth hiatus in 2020.

The below-grade waterproofing market is expected to contract by near 14% in 2020 and then rebound impressively to reach a market size of US$ 1.45 bn by 2025.