Structures that are durable and long lasting. Houses that are safe from extreme weather. Railroads and roads that keep people connected. Hospitals, schools and infrastructure – these are the foundations of our society. Concrete is needed everywhere. Concrete has many properties that enhance the sustainable aspects of a building, such as reducing energy consumption. It absorbs heat during the day and releases it slowly during the night, efficiently moderating the indoor temperature. Structures made of concrete are often designed for a long life and variable use.
What is concrete?
Concrete is one of the most important building materials in the world. It mainly consists of rock and gravel that is mixed with cement, water and additives. Cement is the key ingredient due to its binding properties. The main raw material in cement is limestone that is crushed and ground into a fine powder. The powder is heated at a very high temperature to obtain the intermediate product called clinker. The clinker is ground and mixed with gypsum and various amounts of lime, slag and fly ash to produce different types of cement.
Evaluating the impacts of materials
It is vital to consider the full lifecycle of a building when attempting to compare different construction materials. Cement production is energy intensive and it generates carbon dioxide emissions, but this is only a part of the overall impact of a building.
The wise use of construction materials optimises a building’s functionality and cost efficiency while minimizing overall environmental impact.
Lifecycle assessment (LCA) is used to calculate the environmental impact of individual products over their lifecycle. This includes everything from raw-material extraction, material processing and manufacturing to distribution, usage, maintenance, re-use, recycling or disposal.
The LCA methodology is the basis for Environmental Product Declarations (EPDs). They provide authenticated information about the environmental impact of building material products. We have EPDs for many of our products. In Norway we produce assignment-specific EPDs for ready-mixed concrete.
Environmental classification systems, such as BREEAM, have also seen a rapid increase in our markets in recent years. These systems enable engineers to construct using a well-documented environmental footprint.
Closing the loop
Concrete is a long-lasting material, but it also enables re-use and recycling once it has served its initial purpose. With its inherent strength and binding properties, the concrete may be reused as filler in various applications such as road construction. We are continuously looking into new applications to re-use the material.