Waterproofing buildings used to be an annual pre-monsoon affair but the evolution of real-estate development has changed that approach. In new developments, developers are weaving waterproofing solutions into both the design and construction phases, an approach that Nikhil Madan, Managing Director, Mahima Group, says, “is all about ensuring lasting durability [of the building] and keeping lifecycle risks including water seepage and extensive maintenance to a minimum.”Watertight by designAluminium formwork systems aren’t commonly thought of as a waterproofing tool but at the Mahima Group, these systems and a carefully designed concrete mix help to reduce permeability and fortify structural integrity, he explains. Thereafter, “during the finishing stages, we use fabric mesh reinforcement in plastering to control cracks that could otherwise allow moisture to seep in.”“We also design exposed piping systems, a choice that simplifies both inspection and maintenance, allowing for faster detection of any potential leaks,” adds Madan.Coming to materials, he says, “Chinese mosaic flooring is a popular option for terraces for adding extra protection from water penetration and assisting in the reflection of heat. Additionally, special sealing treatments around the windows and other critical points prevent the penetration of water.”Beyond structural options, the team at the Mahima Group frames a waterproofing plan during the design phase based on the specific requirements of areas such as terraces, toilets, podiums and water tanks, depending on the different amounts of water they are exposed to.“Coordinating the design, engineering, and construction phases so that these waterproofing systems get integrated at the right time during the execution phase can be challenging,” says Madan. “Since many waterproofing systems are concealed, it is very important to supervise the work to ensure it is being done effectively.”Application by areaTranscon Developers’ integrated foundation-to-roof proactive waterproofing strategy spans all its projects, such as Transcon Silver Bay, Bandra (W); Transcon UNO, off BKC; Ramdev Plaza, Santacruz (W); and Transcon Triumph at Andheri (W). “This ensures the structures remain a sanctuary for residents,” says Shraddha Kedia-Agarwal, Director.Starting from basements and retaining walls, “crystalline waterproofing is our preferred waterproofing system for becoming an integral part of the concrete matrix, effectively making the structure self-healing against hairline cracks and being extremely durable, almost permanent, albeit only effective against water under pressure and unable to bridge large structural cracks,” she shares.For expansive podiums and wet areas, Kedia-Agarwal says the crystalline technology is combined with HDPE membrane sheets. “HDPE membranes are highly elastic, which is crucial for handling the thermal expansion due to Mumbai’s climate, and provides a seamless, joint-free finish,” she says, while pointing out that HDPE applications are highly sensitive to substrate moisture and require specialised labour.In a high-speed construction environment, ensuring the concrete substrate is perfectly dry before the HDPE application requires strict scheduling, cautions Kedia Agarwal. “Essentially, the curing window presents challenges.”At Concorde, Penetron, a crystalline, cementitious waterproofing system for concrete, helps achieve water tightness on RCC structures like retaining walls, water bodies, underground sumps, overhead tanks, sewage treatment plants and swimming pools. Also, swell bars seal the construction joints of tanks and water-bearing structures. “Besides forming a seamless elastic membrane when applied, the product offers strong adhesion to different substrates, maintains its mechanical properties across a wide temperature range and is resistant to water, frost and commonly encountered chemicals,” explains Ajaz Ahmed, COO, Concorde.In Concorde’s residential project Concorde Antares and commercial project Concorde Econex, a cementitious polymer dispersion-based flexible protective coating system provides a breathable and flexible protective layer that acts as a reliable waterproof barrier for the balconies, chajjas, toilets, bathrooms and terraces.“Since the coating is self-curing and capable of accommodating minor structural movement, it helps prevent the formation of cracks and water seepage over time,” says Ahmed. “Additionally, a liquid applied polyurethane waterproofing membrane was deployed for high-exposure areas such as terraces, podium slabs and balconies requiring superior long-term protection.”Choose right“Across all our projects, be it Viyaara Altiora at Dadar, Riverside Taloja at Taloja or upcoming developments across Mumbai and the MMR, we always integrate proactive waterproofing systems from the design and construction stage itself, and this includes advanced basement and terrace waterproofing, façade sealing and long-term protection solutions,” says Manoj Paliwal, Director, Viyaara Realty. “We work with proven systems that meet the project’s structural requirements, site conditions and long-term durability standards. Rather than focusing on perceived ‘cons’, we evaluate products based on their performance, reliability and suitability for the specific application.”Paliwal points out that today’s well-informed homebuyers help make the conversation more transparent, and ensure that chosen solutions align with both industry best practices and their expectations. At Concorde, the preference leans toward “relatively easy to apply products that don’t need heat-based processes, as this improves safety during installation”, adds Ahmed.Cost mattersProactive waterproofing systems typically cost about 50 per cent more than conventional repair-oriented waterproofing solutions, says Ahmed. From a lifecycle perspective, this investment is justified, he says, “because it significantly reduces the risk of seepage, structural deterioration and future repair work, while maintaining the asset’s long-term value and ensuring better living conditions for residents”.However, Madan has a different take. Considering the breaking through the finished surfaces, refinishing and multiple maintenance activities involved in carrying out waterproofing as a repair process, he says incorporating waterproofing in the design as part of the construction process keeps the overall cost about the same as, and in some cases less than, the former route.Despite the possibly slightly higher upfront cost of integrated systems, they offer far greater long-term value by preventing issues before they arise, sums up Paliwal. “Besides, today’s homebuyers clearly prioritise quality and long-term durability over short-term savings. Meanwhile, as developers, we ensure buyers receive the best possible materials and systems that enhance the building’s durability and overall lifecycle performance.”