“Mission Zero”—the goal of reaching carbon zero by a specific date—is a priority in many industries, including those of scientists, engineers, and construction companies. Many companies are pursuing both net-zero and absolute-zero goals. The former involves reducing greenhouse gas emissions from business activities, with the remainder offset through approved carbon offset schemes. Absolute zero, meanwhile, involves reducing all greenhouse gas emissions from business operations to zero, without the need for offsets. In construction and industry, one of the key ways to achieve key targets is to use durable materials, which reduce the need for repairs, replacements, and maintenance.
The Current Carbon Costs of Short Lifespans in Construction
Humidity, corrosion, and ground movements can all cause structural or industrial materials to wear out faster than expected. Embodied carbon—the emissions resulting from the extraction, manufacturing, transport, construction, maintenance, and disposal of construction materials—can be as great as the operational carbon involved in running the building (including heating, cooling, lighting, and appliances). Because many modern buildings typically possess optimal insulation, efficient HVAC systems, and renewable electricity, the share of operational energy emissions has dropped dramatically over the years. The same cannot be said for embodied carbon, which accounts for 20-50% of a building’s whole-life carbon.
Durability as a Sustainability Strategy
When selecting materials, constructors seeking to reduce their carbon footprint should prioritize qualities such as longevity, corrosion resistance, strength, and low maintenance requirements. Currently, the longest-lasting building materials include some types of wood, concrete, steel, and brick. In some specialized applications, materials with exceptional corrosion resistance can help boost a building’s overall longevity. Titanium, for instance, is a material known for its light weight, strength, and corrosion resistance. Construction companies sometimes purchase titanium plates for use in chemical processing equipment, marine infrastructure, and desalination systems, where exposure to saltwater and corrosive substances is the norm. Although this material may have a higher initial cost, its unique properties allow it to last for significantly longer, reducing the need for maintenance, replacement, and disposal.
The Environmental Impact of Long-Lasting Materials
Although longevity helps reduce carbon footprints, it is worth noting that many long-lasting materials involve trade-offs. For instance, concrete is long-lasting, fire-resistant, and low-maintenance. However, concrete accounts for 8% of global annual carbon emissions. Steel also has its issues—the chemical reaction used to manufacture this material releases CO2. Excessive timber use leads to deforestation. Finally, masonry involves the use of concrete and the firing of bricks, which rely on fossil fuels. To reach their net-zero or absolute-zero goals, construction companies must focus on materials that are both durable and sustainable.
Materials Boasting Sustainability
One material used by eco-friendly construction companies is mass timber, which stores carbon absorbed by trees during growth and has significantly lower emissions than cement or steel. This material is typically sourced from sustainably managed forests, lasts over 100 years, and performs well in seismic zones owing to its flexibility. Geopolymer concrete, meanwhile, is made from byproducts such as fly ash or slag. It is known to reduce CO2 emissions significantly compared to traditional cement. It also boasts properties such as high chemical and heat resistance, as well as optimal durability in marine and industrial environments.
Bamboo as a Sturdy, Long-Lasting, Resistant Construction Material
Bamboo is one of the most impressive sustainable solutions for many reasons. It is one of the fastest-growing plants in the world, with some species capable of growing over a metre per day. It also boasts high tensile strength and absorbs significantly more CO2 than the same number of trees, according to the International Bamboo and Rattan Organization. Just a few well-known projects using this material include The Arc at the Green School in Bali and Madrid-Barajas Airport. It boasts one of the world’s largest bamboo interiors, with engineered bamboo roof panels covering over 212,000 m2. Additional materials boasting sustainable strength and longevity include recycled steel and advanced alloys.
Companies wishing to achieve Mission Zero must take various considerations into account. On the one hand, longevity is key. Materials that stand the test of time and have qualities such as high tensile strength and anti-corrosive properties require less maintenance and lower sourcing, manufacturing, and disposal costs. However, it is vital to prioritize materials with a low long-term embodied carbon footprint. As such, materials such as bamboo, titanium, recycled steel, and advanced alloys hold great promise for the future.
