Harsha Kavi, Regional Product Segment Manager
Harsha Kavi, Regional Product Segment Manager (Waterproofing/Sealants), Fosroc, explains the current methods to ensure waterproof construction and remedies in case of dampness and leakages in high-rises.

What are the waterproofing challenges in high-rise buildings?
The quality of construction of high-rise buildings has to be extremely good in terms of specifications, materials etc. As buildings go higher, basements go deeper. When basements go deeper, lots of construction joints appear, and the building will undergo uplift pressure, settlements, hydrostatic pressure, seismic movements, etc.

Exposure to ground water pressure combined with quality of urban soil contamination by surrounding effluent release necessitate high quality waterproofing. One cannot afford to apply underperforming material for waterproofing or be negligent in the application quality. Specifiers need to have full information on the merits and demerits of waterproofing systems, accessories and appurtenant systems that augment high-end waterproofing materials.

Harsha Kavi, Regional Product Segment Manager

Since high rise buildings have a lot of inhabitants, to reduce the carbon footprint, one must provide vegetated landscaping. This, in turn, needs the right waterproofing sealing system which can bear the brunt of the water laden soils and the fertilizers used for growing the vegetations. Waterproofing for such situations demands very durable systems which come with a higher cost. Waterbodies may be at the podium level or on the roof and thereby contained within the building. Waterproofing thus becomes a challenge in terms of the durability of the waterproofing system.

Harsha Kavi, Regional Product Segment Manager

Wind-driven rain experienced in high-rises necessitates waterproofing and sealing of window perimeters and service areas. The exterior walls of high-rise buildings are also inaccessible for re-coating and maintenance, which can be problematic.

What are the main factors that contribute to waterproofing failure in high-rise concrete buildings?
Almost 99% of the failures in waterproofing happen due to the 1% of openings and transitions which are not sealed and waterproofed effectively. Before taking up waterproofing, a thorough understanding of the structural and architectural detailing are a must.

Harsha Kavi, Regional Product Segment Manager

Lack of proper detailing is one of the major factors for waterproofing failures. Proposing ‘fit to purpose’ waterproofing is a way. For example, the tensile strength of waterproofing should be higher than that of the substrate’s tensile strength.

Harsha Kavi, Regional Product Segment Manager

Other causes of failure are improper selection of waterproofing system, not carrying out proper preparatory work, use of incompatible materials, design flaws, co-ordination issues (applicator & product owner become the responsible persons for waterproofing execution), incorrect diagnosis of leakage problems, faulty external plastering, and lack of effective monitoring post the application.

Harsha Kavi, Regional Product Segment Manager

Please give examples of the different types of waterproofing systems being applied in concrete buildings and structures.
In every structure, depending on the exposure conditions and serviceability requirements, and in every part of the building, different kinds of waterproofing systems are specified, as shown in the table Table 1:

Table 1
Areas Types / Category (Exposure) Area of application Product / System suggested
SUBGROUND PILES / PILE CAPS WET & DRY Pile Top Epoxy grout
WET & DRY Reprofiling of pile Factory Controlled Repair Mortars
       
FOOTINGS, FOUNDATIONS in RCC WET Below footings Pressure sensitive HDPE membrane
Footings perimeters Self-adhesive HDPE / SBS membranes / PU coatings protected with boards from backfills
       
RAFT WET Below RAFT Pressure sensitive HDPE membrane
Confined  Retaining wall WET On shore piles Sacrificial shuttering and cell mesh bonded to a blended
polyethylene membrane (mechanically bonded)
Sacrificial shuttering and Pressure sensitive HDPE membrane
Un-Confined Retaining wall WET Membrane Self-adhesive HDPE/SBS membranes
Liquid applied Pure Polyurea/Polyurethane coating
         
Podiums Driveways Wet & Dry Liquid applied PU coating
Land scape areas Wet Liquid applied Hybrid PU/ Polyurea
         
Swimming pool Floors and walls Wet Liquid applied Cementitious with negative pressure resistance / PU coating overlaid with Glass tiles or ceramic tiles and gaps filled with UV resistant resinous tile grout
         
Roofs Dry   Liquid applied/membrane Hybrid polyurea / TPO membranes
Landscaped   Liquid applied Hybrid polyurea
         
Bathrooms  All types Always wet Liquid – Brush applied Cementitious coating with good tensile and elongation
Which remedial waterproofing solutions would you recommend?
Roofs of high-rise buildings: Remedial waterproofing in roofs is by far the most complicated. Roofs are usually crowded due to installed units for air conditioning, plumbing pipes fixed onto the roof surface and parapet walls, etc. Sometimes, steel fabricated over-bridges are erected over roof areas, where large sized pipes run over the roof surface. All these need to be relocated and lifted well above the roofing surface or parapet before one can start surface preparations. In domestic situations, the relocation may be far easier, which the waterproofing contractor can take up as a part of his remedial job.

Loose plasters and cracks in surface of the roof need to be exposed with mechanical means along with high pressure water jetting, etc. Once the bare surfaces of the walls and roofing surface are exposed, there could be signs of corrosion seen.

Generally re-roofing requires quite a bit of civil work, which sometimes may be outside the scope of the waterproofing job per se.

Harsha Kavi, Regional Product Segment Manager

In short, there is no straight answer for recommendation of the waterproofing materials, as it is always subjective. A tailored solution needs to be worked out to see that the remedial waterproofing is effective and long lasting.

Wet areas and bathrooms: Here, a superficial remedy must not be done. It is essential to remove tiles. The basic waterproofing must be done by way of brush applied cementitious coatings after repair of plumbing and sanitary fittings. In most situations, old, corroded GI plumbing has to be replaced and relocated in the bathroom. This can include doing up the bathroom interiors with more modern fittings.

In case a bathroom’s base is leaking into the neighbour’s bathroom below, PU Injections may be the most effective solution.

Harsha Kavi, Regional Product Segment Manager

Basement walls: Good materials are available to arrest mild dampness in the interior side of concrete basement walls. Once a dry surface is achieved, it will be safe to coat these walls with decorative paints.

Leaking podiums: The entire area on top of a leaking podium has to be removed and put back in place after the surface preparation, examination, and repair of the deteriorated areas. After this, based on the kind of hard scaping or wet scaping design, appropriate membranes such as pure polyurea or hybrid polyurea can be suggested. The existing expansion joint profiles need to be repaired and re-treated, and then filled with a low modulus high MAF sealant. The sealant all along the podium surface will need to be covered with an aluminum channel cover riveted over, to protect the sealant from the landscaping and soil overburdens.

Harsha Kavi, Regional Product Segment Manager

Please tell us about Fosroc and its areas of expertise.
Fosroc has been manufacturing construction chemicals since 80 years. A UK-based company, it has a strong hold in the Indian subcontinent since the past 40 years with manufacturing and marketing. Fosroc provides all kinds of assistance right from concrete admixtures and surface treatments to waterproofing and industrial flooring. Products include anchors, grouts, protective coatings, adhesives, joint sealants, and cement grinding aids.
Moteurs Baudouin
We are fully geared up with the technological advancements required to meet the CPCB IV+norms with our flexible and dependable power solutions. Gurunath Kulkarni. For over 100 years, Baudouin has been designing the highest quality diesel and gas engines for

Read more ...

Builders Association of India: Bridging the Gaps
Nimesh Patel, President, BAI & Managing Director, Maruti Infrastructure Limited, discusses the challenges and issues faced by the construction and real estate industries of India; why BAI is propagating a Unified Standard Contract Document, and how the

Read more ...

Volvo CE India: Designing Machines to Give Power & Precision
Volvo machines are 10-15% more fuel efficient, they comply with CEV IV emission norms, and can run on alternative eco-friendly fuels such as biodiesel. We lay strong emphasis on operator training for efficient use of every machine that we sell, avers Dimitrov

Read more ...

Tata Hitachi India: Developing Indigenous High-Tech Machines
To serve the Indian infra development sector more industriously, we will continue to undertake extensive R&D and introduce machines with high-tech features, cost-effective solutions, high performance, and fuel efficiency, avers Sandeep Singh, Managing

Read more ...

L&T: Industry Leading Initiatives & Achievements
Arvind K Garg, Senior Vice President and Head, L&T Construction & Mining Machinery, enumerates the technologies and products introduced by Komatsu and L&T, the company’s extensive customer service programs, and proactive skill development initiatives which

Read more ...

ACE: Electrifying the Industry
Sorab Agarwal, Executive Director, informs that the company is set to become India’s first ‘swadeshi’ manufacturer of electric construction equipment with the launch of a fully electric mobile crane, whose technology has been developed indigenously at their

Read more ...

Terex: Strengthening Foothold Across India
Jaideep Shekhar, Managing Director, Asia & EMEAR, informs that the company will continue to strengthen its foothold in the Indian market by bringing in new technologies, expanding its product portfolio, and entering new construction territories. Its aim is to

Read more ...

Schwing Stetter India: Formulating Plans to Adapt to Demand Trends
V.G.Sakthikumar, Managing Director, informs that since sustainability is an integral part of the company, they are pursuing collaborations and R&D to bring innovative solutions, increase usage of green energy in its facilities, and reduce carbon

Read more ...

Escorts Kubota: Prioritizing Customer Benefits
Sanjeev Bajaj, Chief Executive, Escorts Kubota Limited, is confident that 2023-24 will be a great year for the CE business and demand may be more than the current capacity, largely led by domestic consumption due to the infra push by the Government before the

Read more ...

Puzzolana Group: Increasing Operational Efficiencies
Abhijeet Pai, President, informs that the company’s wide ranging value-added services for its customers has positioned it as a total solution provider in the Crushing & Screening Industry. The focus at bauma this year will be on M-sand, aggregates, railway

Read more ...

Sany India: In Sync With Changing Trends
Dheeraj Panda, Chief Operating Officer - Sales, Marketing & Customer Support, Sany India, informs that the company has taken a significant step forward towards sustainability with its B-V biodiesel machines, and is also testing electric technologies for

Read more ...

CRCHI: Making Tunnel Construction Smarter & Safer
CRCHI is positioned in world markets as a large enterprise with a strong focus on research, design, and manufacturing of customized underground engineering and rail transit equipment, informs Song Shuang, Vice Managing Director, Overseas

Read more ...

Manitou South Asia: Widening Industrial Footprint in India
Hafeez Khan, Managing Director, informs that the company is well-equipped to meet the higher anticipated demand in FY23-24 with its versatile material handling solutions, value-based services, and strategic partnerships with rental companies. Bauma is the perfect

Read more ...

KYB Conmat India: Focus on India-Centric Equipment
Premraj Kashyap, MD, informs that the company is fully geared up to meet upcoming demand in FY23-24 and has added a lot of innovative products to their Concrete Equipment portfolio, including a new range of Self-Loading Concrete Mixers. The government intends

Read more ...

JCB India: Committed to India’s Growth Story
Sales of construction equipment, a barometer of economic activity, is expected to increase in double digits in the ongoing financial year on the back of increased government spending on infrastructure projects, especially in rural areas, observes Deepak

Read more ...

Wirtgen India: Enabling Sustainable Construction
The Wirtgen Group and John Deere are working on various smart technologies, including electric machines, and on sustainable construction through its recycling business, informs Ramesh Palagiri, Managing Director & CEO. Wirtgen’s production systems are

Read more ...

Ammann India: Forging Ahead
Anand Sundaresan, Managing Director, discusses the grey areas in the construction equipment industry of India and how the company’s technologically advanced systems and processes can help meet many of the challenges; and factors that are differentiating

Read more ...

CDE Asia: Sourcing Sand Ethically for the Construction Industry
With the advanced recycling solutions now available, it is possible to achieve a self-reliant, circular economy where different waste streams can be recycled and converted into high-quality sand and aggregates for use in construction, informs Manish

Read more ...

Etrack: Offering the most Advanced & Green mobile Crusher & Scalpers in India
Keestrack is introducing the most advanced and innovative technology for crushers and scalpers through its manufacturing facility in Neemrana, Rajasthan. Swaminathan Dhandapani, CEO, discusses the company’s strategies to drive business in India

Read more ...

LiuGong India: Committed to Make in India
Nischal Mehrotra, Vice President - Sales & Marketing, informs that the company has expanded its product offerings with large tonnage excavators, mini excavators, dozers, electric wheel loaders and trucks, and is geared up to meet the anticipated higher

Read more ...

×
Sign-up for Free Subscription
'India Construction Week'
Weekly e-Newsletter on Construction Industry
Get the latest news, product launches, projects announced / awarded, government policies, investments, and expert views.
Click here to subscribe.
×