The construction sector provides the buildings and infrastructure needed by the rest of the economy and society. This includes the extraction of materials, the manufacturing and distribution of construction products as well as the design, construction and management of construction works.
As can be seen in the figure below, the construction sector is one of the largest consumers of resources in the EU, as it consumes about 50% of the materials extracted in Europe. The sector is also globally responsible for more than half of greenhouse gas emissions. In the EU, building materials alone have an annual CO2 footprint of 250 million tonnes. Construction also requires large amounts of water and energy. The construction sector accounts for around one-third of the EU’s freshwater consumption and buildings are responsible for about 60% of global energy use. Additionally, the construction and demolition of buildings and infrastructure generate a lot of waste, accounting for over one-third of the EU’s total waste generated.
While the sector has some major environmental impacts, it should be noted that the sector is also of great size. The construction sector is the EU’s leading industrial employer. The sector directly employs about 19.8 million people, which is about 4.4% of the total EU population. The EU Member States with the most people working in construction are Germany and France with 4.5 million and 2.3 million workers, respectively. Additionally, with a turnover of 2.66 trillion euros in 2020, the construction sector contributes to roughly 9% of the EU’s GDP. The highest construction turnover also comes from Germany and France, who collectively account for 40% of the total construction turnover.
Figure 1, EU construction sector impacts, own image.
The construction sector is one of the EU’s largest consumers of resources. The sector’s main materials used are concrete, clay and aggregates, such as sand and gravel (Herczeg, et al., 2014). The main bio-based construction material is wood, which can be used for the framing and structures of buildings. About 70% of wood consumed in the EU is used in furnishings and construction and an estimated 8-10% of EU single-family homes have a wooden frame (European Commission, n.d. b). The majority of wood used in construction is softwood, as this is typically less expensive as it usually grows faster than hardwood and can be of lower quality (Diffen, n.d.). As can be seen in the figure below, solid timber products can be used in construction, such as beams, planks and posts, but wood can also be modified (potentially using bio-based additives) to create an engineered wood product (EWP). These man-made wood products can offer benefits, such as greater strength and durability. The three main types of EWPs are panel products, such as plywood and fibreboards; mass timber products, such as cross-laminated timber (CLT) and glue-laminated timber (glulam); and structural composite lumber products, which includes laminated veneer lumber (LVL) and oriented strand lumber (OSL) products. As the strength of some of these EWPs is comparable to steel, the use of these products in construction means the possibility of greater and taller wooden buildings and increased use of wood in construction (Hetemäki, et al., 2017).
Figure 2, Overview of bio-based construction materials, own image.
There are also other bio-based materials used in construction, including bio-composites. Composites are formed using a combination of two or more materials. The added components have a functional and specific contribution to the composite material, as they are used as reinforcement, a filler, dye or coating, etc. Commonly used composites in the construction sector are concrete and fibreglass, in which plastic is reinforced using glass fibres (Williams, n.d.). There are also various types of composites which use bio-based components, such as agricultural residues, and fibres, including wood, flax, jute and bamboo fibres. These bio-based fibres can be used to reinforce materials, creating products such as fibre cement (van Dam & van den Oever, 2019).
While most insulation materials within construction are made out of mineral wool or plastic foams, there are also bio-based alternatives (Pavel & Blagoeva, Competitive landscape of the EU’s insulation materials industry for energy-efficient buildings, 2018). The bio-based insulation market is expanding and is estimated to have grown by 40% over the last three years to a market share of about 10% of insulation (Lecompte & Picandet, 2022). The most commonly used bio-based insulation materials come from wood fibres, cellulose from recycled newspapers, straw, and plant fibres, such as from hemp, cotton and flax (Schulte et al., 2021). There are various other (less-commonly used) bio-based materials for insulation, such as seagrass, lime from shells, mycelium, reed, rice husks, coconut husks, natural cork and sheep’s wool (van Dam & van den Oever, 2019).
There are several ways to assist improving the environmental impacts of the construction sector. This includes the use of building certifications, such as BREEAM and LEED; material certifications, such as Cradle-to-Cradle, PEFC and FSC; various ISO and EU standards; and the utilization of environmental assessments, such as Environmental Product Declaration (EPD), Product Environmental Footprint (PEF) and Life Cycle Assessment (LCA). LCAs can be used to assess the environmental impact of materials, products and services. This way, it can be used as a decision-making tool towards sustainability. LCAs can be applied to a wide range of sectors, including the bio-based construction sector. The EU Horizon Europe ALIGNED project looks at LCA methodology and aims at improving, harmonizing and aligning LCA assessment methods in the bio-based sector.
The EU is working towards a more circular construction sector with an increased energy efficiency. Insulation materials play a great role in improving the overall energy efficiency and sustainability of the EU’s buildings. The insulation of buildings is a major technology in saving energy and resources. By improving the energy efficiency of buildings, energy losses through walls, floors and roofs can be avoided. While the most common insulation materials are made out of mineral wool (glass wool and rock wool) and plastic foams (EPS, XPS and PUR ), the use of bio-based insulation materials is growing at a significant rate (Pavel & Blagoeva, 2018). The bio-based insulation market has grown by 40% in the last three years and is estimated to now have a market share of 10% in the EU (Lecompte & Picandet, 2022). As such, both insulation and bio-based materials are important to the development of the EU construction sector. The environmental sustainability of bio-based insulation materials will therefore be further examined in the ALIGNED project.
Diffen. (n.d.). Hardwood vs. Softwood. Retrieved from Diffen: https://www.diffen.com/difference/Hardwood_vs_Softwood
ECSO. (n.d.). European construction sector observatory (ECSO). Retrieved from Internal Market, Industry, Entrepreneurship and SMEs: https://single-market-economy.ec.europa.eu/sectors/construction/observatory_en
European Commission. (n.d. a). Buildings and construction. Retrieved from Internal Market, Industry, Entrepreneurship and SMEs: https://single-market-economy.ec.europa.eu/industry/sustainability/buildings-and-construction_en
European Commission. (n.d. b). Woodworking. Retrieved from Internal Market, Industry, Entrepreneurship and SMEs
Herczeg, M., McKinnon, D., Milios, L., Bakas, I., Klaassens, E., Svatikova, K., & Widerberg, O. (2014). Resource efficiency in the. Rotterdam: DG Environment.
Hetemäki, L., Hanewinkel, M., Muys, B., Ollikainen, M., Palahí, M., & Trasobares, A. (2017). Leading the way to a European circular bioeconomy strategy. From Science to Policy 5. doi:https://doi.org/10.36333/fs05
Lecompte, T., & Picandet, V. (2022, 10 4). Bio-based materials improve the comfort and carbon footprint of buildings. Retrieved from Polytechnique insights: https://www.polytechnique-insights.com/en/columns/planet/bio-based-materials-improve-the-comfort-and-carbon-footprint-of-buildings/#note-11
Pavel, C., & Blagoeva, D. (2018). Competitive landscape of the EU’s insulation materials industry for energy-efficient buildings. Petten: Joint Research Centre. doi:https://data.europa.eu/doi/10.2760/750646
Pavel, C., & Blagoeva, D. T. (2018). Competitive landscape of the EU’s insulation materials industry for energy-efficient buildings. Petten: Joint Research Centre (European Commission). doi:10.2760/750646
Pozzi, F. (2022, 03 29). It’s time to green the construction sector. Retrieved from Environmental Coalition on Standards: https://ecostandard.org/news_events/its-time-to-green-the-construction-sector/
van Dam, J., & van den Oever, M. (2019). Catalogus biobased bouwmaterialen. Wageningen University.
Williams, J. (n.d.). The science and technology of composite materials. Retrieved from Australian Academy of Science: https://www.science.org.au/curious/technology-future/composite-materials