A greener build

C&I Issue 4, 2015

The global construction chemicals market – which includes concrete admixtures, asphalt additives, protective coatings and adhesives and sealants – was valued at $21.12bn in 2013 and is anticipated by market research firm Transparency Market Research (TMR) to reach $37.68bn  in 2020, expanding at a compound annual growth rate (CAGR) of 8.7%. When caulks, grouts and mortars, and polymer flooring are included, Global Industry Analysts (GIA) has even greater expectations, with forecasts reaching US$46.4bn by 2020. Concrete surface treatments, waterproofing materials, wall claddings and sprayed polyurethane foam insulation are also construction chemicals.

Owing to its growing middle class population and rising urbanisation, China was the largest consumer of construction chemicals in 2013, accounting for more than 40% of the global market, according to TMR. Concrete admixtures were the largest segment, comprising more than 55% of the market. Demand for concrete and asphalt additives is driven by growth in emerging markets, while demand for high-performance protective coatings, adhesives and sealants for the restoration of older structures is greater in developed countries.

In addition to improving the appearance of structures, construction chemicals impart properties to building materials, including resistance to damage from chemicals, moisture and corrosion, resistance to heat flows and adverse climatic conditions, enhanced durability and strength. Consequently, they are used in all construction projects, accounting for 2–3% of the overall cost of a given build, according to GIA. Five years ago, the American Chemistry Council estimated in its Year-end 2010 situation and outlook report that a single-family housing unit consumed, on average, over $15,000 worth of construction chemicals.

While manufacturers strive to develop higher-performing, more sustainable materials for buildings, explains Timothy Serie, counsel with the American Coatings Association, the ‘green building movement’ looks to create incentives for innovative areas. Initially, for example, the movement focused on low-VOC adhesives, sealants and paints and products such as MDF particleboard with no urea formaldehyde but is now embracing materials that increase a building’s energy efficiency, greater use of recycled and renewable materials and reducing the carbon footprint of manufacturing processes.

In December 2012, the International Council of Chemical Associations (ICCA) reported that the building sector accounted for nearly one-third of the energy consumed in the US, and by 2050, the percentage would increase by more than 62%. The increased awareness of the importance of energy efficiency has resulted in the development of many more green products.

Michael D. Brown, president of specialty chemical consulting firm StrategyMark, points out that polyurethane roofing panels and coatings are low-VOC alternatives to asphalt that provide insulation to reduce energy loads and thus cooling needs during warm weather. High-performance fluoropolymer-based coatings for steel roofing, which have very low surface tension, not only extend the life of these roofs, but also enable the collection of high-quality rainwater in areas where water shortages are common, according to Ray Will, director of IHS Chemical Consulting.

Other coating products of note include reflective wall coatings; thermal barrier coatings; interior radiation control coatings (IRCCs) that are applied to the underside of attic roofs and block transmission of radiant energy from the roof; thermochromic and electrochromic coatings for glass, for heat management; and interior wall paints that reflect visible light, reducing the need for artificial lighting.

Demand for polyurethane (PU) foam, which can be applied in various forms in different areas of a building to provide insulation, is also increasing. Such products are now available with increased fire resistance, while PU adhesives are replacing physical fasteners for roofing insulation to provide a complete barrier.

Spray polyurethane foam (SPF) insulation is an innovation that can be linked directly to the green building movement, according to Trent Shidaker, business manager at Huntsman. Functioning both as an insulator and an air-sealing product, SPF can save up to 50% of utility costs, resulting in increasing use in residential and commercial building markets. ‘These segments consume more energy than transportation or industrial segments, making SPF insulation an effective solution for reducing energy usage and CO2 emissions,’ Shidaker adds.

Renewable feedstocks for the production of construction chemicals is also on the increase. ‘It is very interesting that even though green buildings are a minor part of the construction materials market, they are driving outsized innovation,’ Brown observes. Formaldehyde-free fibreglass insulation and plasticiser-free sealants are already on the market.

The environmental profile and performance of concrete are also being improved with chemical technologies. Densifiers help protect against freeze–thaw damage, while high-performing water repellents and sealers protect against water penetration. The replacement of cement in concrete with waste materials – fly ash, wood fibbers, glass waste, recycled concrete etc – together with novel admixtures is providing the final product with a range of performance properties. Superplasticisers, or high-range water reducers, allow for the reduction of water content in self-consolidating concrete (SCC) while also improving its fluidity and strength. Admixtures are also available that extend the workability time for concrete, reducing waste.

Challenging times

The green building movement is also associated with voluntary certification programmes, including the Leadership in Energy and Environmental Design (LEED) rating system, the Building Research Establishment Environmental Assessment Methodology (BREEAM), the High Quality Environmental (HQE) standard and the Deutsche Gesellschaft für Nachhaltiges Bauen (DGNB) system. But there are many other programmes. Indeed, the large number of programmes is one of the challenges facing the construction chemicals industry as many of them have very different requirements.

Another challenge is the identification by many of these groups of lists of chemicals that they believe are hazardous. Often the lists are different, and some groups have limits on the quantities of listed substances, while others do not. ‘The advent of “red lists” of hazardous chemicals poses a huge challenge to manufacturers, since such lists do not contribute to a rational and scientific evaluation of risks to occupants from exposure to such materials, at the least because no exposure pathways are identified,’ asserts Jerry Yudelson, president of the Green Building Initiative (GBI). He adds, however, that many leading architectural firms are on record as committed to ‘deselecting’ any building materials that contain chemicals on these ‘red lists’, and therefore chemical manufacturers should be aware of the power of such lists.

‘Although the chemical industry has had a strong voice in many aspects of green chemistry development, I would like to see more cooperative and data-driven decision making around the generation of “red lists” that look to ban certain chemicals used in any amount without regard for the performance tradeoffs that designers run into because of the lists,’ adds Matthew Lendzinski, field marketing manager for Dow Construction Chemicals.

Serhan Oztemiz, technology manager with Bostik would also like to see non-governmental organisations (NGOs) work together with manufacturers to develop standards rather than imposing them on the chemical industry via architects and designers. Serie agrees. ‘Product manufacturers have a critical role to play in the development of robust green building standards by providing technical expertise and an unmatched understanding of a product’s chemistry, manufacturing process, supply chain and application. While manufacturers have contributed to the growth of green building, their voices have at times, unfortunately, been excluded from the development of some green building programmes. Our hope is that all green building programmes will become more inclusive and consider the views of all affected stakeholders.’

Brendan Owens, chief engineer at the US Green Building Council, which develops the LEED programme, notes that chemical manufacturers participated in the development of LEED through volunteer technical advisory groups, public comment periods and formal meetings. In addition, he notes that their support of LEED projects and the feedback USGBC receives have been very important to the success of the initiative.

Shpresa Kotaji, Huntsman’s environmental affairs manager and an active member of the European standardisation committee on the sustainability of construction work, and Dirk Funhoff, member of the board of directors at the German Sustainable Building Council (GeSBC) and head of the European Construction Competence Centre at BASF, agree that chemical manufacturers have many opportunities to get involved and have a say in how the green building movement evolves. As an example, Huntsman is a founding member of EuroACE – the European Alliance of Companies for Energy Efficiency in Buildings, which commissioned a series of reports that show that building energy efficiency measures, including insulation, could save over 400mt of CO2 annually and, furthermore, that this approach would be very cost effective when compared with alternative measures, such as renewable energy. These proposals have resulted in building energy efficiency being highlighted in a draft EU Climate Change programme and in the Directive on Energy Efficiency.

A third concern for the industry is that in some cases certification requirements are becoming de facto regulatory standards because they are integrated into local government-mandated building codes or are preferred for government-owned buildings. In fact, green building certification programmes have had the greatest impact in ‘policy-driven’ markets such as government and corporate buildings, and universities, according to Yudelson. Often, avoidance of particular ‘red list’ chemicals in building materials can be used to accumulate the points needed for certification.

To address this issue, GBI is updating its 2010 new construction standard for the Green Globes system using an American National Standards Institute (ANSI) consensus process to ensure that all affected parties will have the opportunity to debate their points of view and resolve their disputes. ‘The Green Globes green building rating system for new construction represents consensus standards based on the best available scientific evidence,’ Yudelson states.

Other standards, such as the requirement for continuous insulation, are also science-based. In fact, as the understanding of building science, heat flows and energy efficiency has improved, manufacturers have been able to test and validate their products and consequently develop materials with improved performance.

Such a holistic approach is needed for all assessments of sustainability and ‘greenness’ in the construction industry, according to Funhoff. ‘Any assessment should be based upon a lifecycle assessment (LCA), including the use phase based upon clearly defined performance measurements.’ There are no ‘sustainable materials’, he adds, but there are more or less sustainable applications of materials. The advantages of one material in a specific application cannot be transferred to another application. In general, he points out, the challenge for green buildings is very much on the application, as the intelligent and sustainable use of materials (ie resource efficiency) is much more important.

Green building certification programmes like Environmental Product Declarations (EPDs) help to increase the transparency of the environmental impact of building materials from production through use and the end of the life of the product, according to Tim Lacey, global business director for Dow Building Solutions.

‘Programmes like these are important and provide the industry with access to a deep level of information on products they’re using in their buildings. Greater detail on the environmental impact of building materials is important to the industry and the growth of this awareness is positive for the future of building and construction.’

As the industry gets smarter about environmentally-preferred certifications, analysis and other related programmes, says Lacey, there should be greater attention to risk of building material ingredients based on application versus the risk of the ingredient itself. He notes that Dow’s building science experts are increasingly focusing on the health and safety of occupants and preparing for this natural next step within the building and construction industry.

Funhoff also expects to see an increase in LCA-based and performance-driven certification systems that will require more transparency about the ecological, economical and societal contributions of construction materials to the sustainability of a building. ‘As the resource requirements during the operation of a building are reduced [zero-energy-buildings], the resources needed to produce the building will receive more scrutiny. LCAs will make that very visible and will further encourage producers to optimise their processes not only financially, but sustainably,’ he says.

Owens agrees that multi-attribute LCA-based decisions provide a better framework for the future. ‘We are moving toward optimisation of multiple attributes, which will allow for more informed decision making by project teams. With more information about raw materials, they will be able to determine the tradeoffs and make better choices,’ he explains.

However, Lendzinski cautions that when new products can deliver equal or better performance at equal cost, adoption occurs quite quickly, but if there is not cost parity between the ‘green’ option and the conventional technology, most industries will resist change without market pressure in the form of either strong consumer aversion to certain ingredients or regulatory drivers.

‘Having certified products does not guarantee that you will win contracts,’ adds Oztemiz. ‘There have been occasions where a lower VOC product at a higher price wins over a conventional adhesive at a cheaper price, but if a particular job does not require a certified product, the premium price associated with certification will often lead to loss of the contract.’

Even so, Oztemiz believes that the green building movement will inevitably change the face of the construction chemicals market.

Cynthia Challener is a freelance science writer based in Vermont, US

Become an SCI Member to receive events discounts

Join SCI