The construction industry is one of the biggest global emitters of carbon dioxide. One way to change this is to use sustainable and renewable raw materials, such as wood. Load-bearing glued timber construction is considered a central element in the necessary transition towards a more sustainable future of the construction industry.
The production of sustainable building products which store CO2, such as cross-laminated timber, requires not only the valuable resource wood from local forests, but also reliable adhesive systems. Leading manufacturers in the timber industry have therefore relied on Henkel Engineered Wood’s Loctite adhesives for many years.
Improving what is already good
In wood-metal connections, such as glued-in threaded rods, the Loctite CR 821 ECO plays to its strengths © Henkel Engineered Wood
Although it might seem that adhesives are just a small part of solid timber construction products as a whole, there is a lot of room for improvement especially in this area. Alternative solutions, which help reduce CO2 emissions even further and thus make load-bearing glued timber construction even more sustainable, are needed.
Henkel recognized this and recently launched two new glue formulations, Loctite HB S ECO and Loctite CR 821 ECO, which have a cradle-to-gate product carbon footprint which is more than 60% lower than that of conventional fossil products (based on Henkel’s internal life cycle analysis). All low-emission adhesives are tested according to the highest standards and have all relevant documentation, such as life cycle assessments and certificates from the International Sustainability and Carbon Certification (ISCC) system.
Demonstrable reduction of emissions
A look inside Henkel’s laboratory © Henkel Engineered Wood
Loctite HB S is a one-component PUR adhesive, which is free of volatile organic compounds or solvents. The adhesive contains 63 percent by weight of bio-based raw materials in the organic material according to the mass balance approach. According to Henkel, these raw materials are mainly composed of old vegetable oils and other organic waste.
“Using the well-known and established mass balance approach, which is similar to the green electricity principle, the new ECO product line enables us to reduce carbon equivalents,” Dr. Christian Fild, Head of Henkel Engineered Wood, explains.
Compared to the conventional formulation, the emissions of the ECO line are 66% lower, as Henkel states.
Our Loctite HB S line is one of the leading established products in the European glued timber construction sector. With our ECO line, we can make a major difference and a valuable contribution to making timber construction even more sustainable.
Green product with improved performance
A look at impressive timber construction projects, in which Henkel was involved, such as GlaxoSmithKline’s headquarters in Brentford, West London, ... © Stéphane Groleau / Henkel Engineered Wood
With Loctite CR 821 ECO, Henkel has developed a two-component PUR resin which contains mostly renewable raw materials. This product is mainly used for load-bearing, invisible timber construction connections, such as glued-in threaded rods.
“Often, the problem with bio-based adhesives is their poor performance, which is why they cannot be used in load-bearing timber structures. With our CR 821 ECO, the exact opposite is the case. It meets the highest national and European requirements in accordance with building authority approval Z-9.1-896 and the EN 17334 norm,” Henkel’s Certification Manager Gordian Stapf explains, addressing possible uncertainties about the performance of sustainable adhesive systems.
“Thanks to a combination of directly bio-based and mass-balanced raw materials, renewable raw materials account for 71 percent by weight of the organic mass of the Loctite CR 821 adhesive. This high percentage results in a significantly smaller carbon footprint compared to two-component PUR adhesives made purely from fossil raw materials,” Dr. Claudia Meckel, Head of Global Product Development, explains. “It is important to us that the organic raw materials we use are not in competition with other primary forms of use. For this reason, we only use biocircular raw materials,” Fild adds.
Added value for the customer
… or Shane Homes YMCA in Calgary/CA designed by GEC Architecture © Henkel Engineered Wood
The new adhesive systems also open up new possibilities for architects and builders since they help reduce the emissions of the entire project even further while offering the proven quality and reliability of Henkel’s Loctite adhesives.
According to Henkel, absolutely nothing changes for the user. No changes need to be made to the product or the mixture of the adhesive components. Existing approvals also remain in effect and are fully valid for the new ECO adhesive as well. “In addition to the positive aspects regarding sustainability, this was one of the decisive factors that convinced us to switch to ECO adhesives,” Sven Bill, managing director of the innovative Swiss company TS3, tells us.
The still young company, which was established in 2014, wants to further advance the timber construction industry with its front-side gluing of CLT elements and by showing architects and builders completely new ways to build the same projects in wood instead of using concrete. “The great thing about our solution is that we can create large-area elements with a column spacing of up to 8 by 8 m by gluing individual CLT panels on their narrow edges. “This makes TS3 a truly sustainable alternative to concrete,” Bill summarizes.
Henkel Engineered Wood was involved in the innovative product development right from the start. “Henkel developed the formulations for both our pre-treatment paint and the casting resin for the connecting joint. We have a long-standing and successful partnership with the company. TS3 welcomes Henkel’s step towards bio-based adhesive systems. ECO adhesives fit perfectly into our overall image and corporate philosophy. It is important that companies like Henkel also develop further in this area and thus make a valuable contribution to making timber construction even more sustainable,” Bill says, who is convinced of the new ECO line of Henkel Loctite.
