In the next in a series of features on building materials, K Balasubramanian, Vice President (Projects), CR Narayana Rao Architects & Engineers, shares an architect and consultant’s view on the use and abuse of construction chemicals by the Indian construction industry.Modern construction materials are evolving to meet the changing needs of the construction industry. Construction companies are taking on the challenge of completing major works in shorter time frames, often as fast-track projects. They are also constructing more buildings that lay stress on energy and green concepts. This changing pace and portfolio is reflected in the wide-ranging array of available construction materials, including construction chemicals. Chemicals are empowering the industry to design high-performance, taller, and larger scale buildings that are eco-friendly and long-lasting. But the use of construction chemicals comes with several riders. Sometimes, these provisos are adhered to. Sometimes they are ignored, citing the excuse of inconvenience, margins, or even plain ignorance.K.Balasubramanian, Vice President (Projects), CR Narayana Rao Architects & Engineers, Chennai, shares his take on the use (and abuse) of construction chemicals with Charu Bahri. Excerpts…Myriad choices: The past decade has seen a quantum leap in the availability and use of construction chemicals. Today, chemical offerings are largely bifurcated into five categories: concrete and mortar admixtures, waterproofing compounds, floor hardeners, protective coatings and resins, and adhesives, sealants and grouts. Construction chemicals have found wide use in building construction as well as repairs and renovation. Research is yielding many innovative chemicals to meet the specific needs of the industry. For instance, concrete and mortar admixtures, namely plasticisers and retarders, is one group of construction chemicals that has emerged from the need to build taller, larger, faster and more economical residential, commercial and industrial buildings. The changing cityscape also necessitates these chemicals. The greater number of tall buildings being constructed, often in congested downtown areas where there is hardly any working space, leaves contractors with no choice but to turn to ready-mix concrete (RMC). Plasticisers and retarders help retain workability and pumpability, by maintaining plumb with no loss of strength of RMC while it is transported from the plant to site.Use with caution: While construction chemicals are seen as very useful, their application comes with a need to adhere to specifications. To continue the same example, plasticisers and retarders are meant to be used in a certain proportion. Ideally, the process of adding the admixture to the mix should be supervised. In spite of taking this precaution in the plant, sometimes extra chemical is added to the material in transit, to tide over traffic delays. This causes the concrete to lose strength. We openly advocate the testing of concrete cubes made at site for quality monitoring. But at best, this can happen parallel to the usage of the material at the site, which means that such tests only yield post construction results. So, there is not much that can be done to remedy the situation if the material is found wanting. The way out for construction companies committed to high quality standards is to monitor the delivery process. The use of inferior concrete, as a result of the abuse of construction chemicals, creates structures that need repairs much earlier. Repairs also mandate the use of construction chemicals, to try to reverse the damaging effect of inferior material or shortcuts in the construction methodology or at times, to overcome the ravages of weathering, such as corrosion, spalling of concrete, etc.Don’t misunderstand ‘specifications’: On one hand, the industry is enjoying an increasing access to a wide array of construction chemicals. Offerings are being marketed as ‘user-friendly’. It is true that chemicals are making the process of construction much easier. For instance, self-levelling concrete is being used to create abrasion-resistant and long-lasting industrial flooring. This product is far easier to use than the older way of using a concrete screed and a locally available hardener chemical for the same purpose. Most chemicals can nowadays be applied easily with a brush or sprayed on using guns, in a thin layer, and offer similar or better outcome than a decade ago. Then, chemicals needed to be blended with concrete mixes or plaster, or applied in thick layers. Modern products increase access to and hence the usability of a structure. As an example, waterproofed terraces used to be out of bounds for fear of spoiling the coating layer on the floor. Now, no such restriction applies. But, there is a flip side to the ‘user-friendly’ tag given to these latest generation of construction chemicals. A huge section of the industry takes this to mean that anyone can apply the product, even unskilled labour, as long as instructions are followed. Nothing could be more untrue.Applicators wanted: Construction chemicals are sophisticated inputs to the construction process that add value only if they are used as per specification. This means, both the method of application as well as end use has to be right. India sorely lacks trained applicators. The vast majority of chemical companies are highly specialised, churning out a few products for specific applications, such as waterproofing or insulation coatings. These companies train applicators in their own product range. As a result of this, applicators are mostly attached to one vendor. We lack specialists who understand the methodology of using comparable products from different companies.Yet application expertise is crucial to the success of speciality construction chemicals. The industry must invest in training applicators and raising standards in application techniques with the support and help of construction chemical companies to ensure that chemicals are used in consonance with the product tag.Understand end use: Ignorance also abounds with regard to the end use of a product. I recollect a self-foaming polyurethane product meant for insulation, which was hailed in India as a non success for waterproofing or crack filling. Actually, the problem lay in the applicability of the product. Some contractors or applicators misunderstood the product tag. The product was widely used for waterproofing as well as filling cracks and pores; even though it was not intended for such use. Its application method was not adhered to and this led to the product being considered a non success.Towards better supply: While multinational players with a presence in the Indian market are making efforts to educate end users, a lot remains to be done to raise awareness levels about construction chemicals across the industry. Ignorance about use of chemicals damages the prospects of the industry and discourages some international brands from launching their entire range locally. The Indian market is populated by small localised suppliers, some in collaboration with foreign companies, pan-India players, and multinational companies. BASF Construction Chemicals, Fosroc Chemicals, SIKA Qualcrete and Zydex Chemicals are a few reputed companies. As the market is highly competitive, some new overseas entrants try to make inroads into the sector by staying in touch with consultants responsible for drawing up the list of specified construction chemicals to be used for a certain project.Acting with responsibility: As consultants, we understand the huge responsibility that lies on us to verify the efficacy of any new product prior to specifying it for a project. On one hand, we have an interest in widening the market for genuinely good products. On the other hand, we face a huge risk in doing so. We evaluate the test results of new products for their suitability to the proposed applications. We also insist that the manufacturer oversee the application or at least conduct a site inspection to verify the application. I strongly recommend that construction companies call in a company representative when they use newer products, if this is not made mandatory in the material usage specification.The import imperative: Imported chemicals can widen opportunities and improve the outcome of the construction industry. For instance, some imported construction chemicals work better than what is locally available, such as those used for overdeck insulation to reduce the energy load of a building. Also, chemicals used to repair and rehabilitate old buildings, such as lacquer coatings and water repellent coatings used on natural stones, are best imported until the manufacturing technology to make high-quality chemicals is established in India. Contractors using these chemicals must factor in the lead time of four to eight weeks in the supply chain. Some scheduling on part of the user is essential. In contrast, chemicals made in India are usually never in short supply.Estimating future prospects: The industry is in its infancy and has a long way to go. In future, I expect the use of all kinds of chemicals to increase, including those that are presently imported, such as chemicals used to prolong the life of structures and make them eco-friendly. The uptake of external insulation (reflective coating) chemicals, composite roof insulation cum waterproofing chemicals, and self-compacting concrete for complex or thin concrete members that find use in green buildings is also bound to increase as the industry gears up to meet the challenge of protecting the environment and buildings and their occupants from the environment. Nanotechnology is the latest rage in waterproofing and painting/coating. Its use will grow. Polymer-based chemicals used to enhance the wear and tear of bitumen roads will be increasingly sought after as more highway projects are awarded. Prevailing trends such as the focus on reduc-ing input costs will intensify and increase the adoption of chemicals. Chemicals are known to help increase the life and strength of concrete. The use of construction chemicals increases the cost of inputs by a minimal percent, which is much lower than opting for high-strength concrete grades like M60 and above. Leading manufacturers have come together to form the Construction Chemicals Manufacturer’s Association (CCMA) as a platform to address issues of common concern. Hopefully, this will spell better times ahead for the industry and end users.