What if all building materials could be recycled?
It’s an important question for the building industry at a time when we need more buildings but also need to reduce their overall impact on the environment.
It’s now available in 24 countries and our aim is to reach 30 by 2030*. How it works is fairly simple. We take back stone wool material from construction, renovation and demolition sites and recycle it in our production process to make new ROCKWOOL products.
Because the construction industry has a waste problem. Valuable materials are too often uncollected and misdirected to general waste, which ends up in landfill. In fact, only 20–30 percent of construction and demolition waste (CDW) is recovered at all1, indicating the urgent need to tackle this problem.
Our sustainability goals relating to circularity
Rockcycle facilitates a truly circular and closed loop recycling system. It also caters to the increased demand by key stakeholders such as architects, specifiers, engineering and construction companies, public authorities and policymakers for sustainable ways to reduce construction and demolition waste.
As a circularity frontrunner in the construction industry, we are constantly pushing the boundaries of making our products, operations and supply chain more circular. We are keen to engage with ambitious players and regulators at all levels of government on how to best create conducive legislation and a level playing field for circular construction products.
Grodan, a brand within the ROCKWOOL Group, produces substrates for the horticulture industry, which allows for precision growing of vegetables, fruits, herbs and plants. The Grodan stone wool material is collected and sent for recycling with the majority being recycled externally (open loop) to the brick industry and as a soil improver as examples. As part of the commitment to the circular economy, Grodan has built a network of partnerships and collaboration agreements with leading recycling organisations in North America, Europe, Asia, and Australia and recycle thousands of tons of stone wool every year. The aim is to make Grodan stone wool solutions one of the most effectively recycled products in the world.
Read more here.
To make the circular economy work, the world needs more than just products like stone wool that meet requirements. We need to build an ‘economy’, or ecosystem, around the concept that helps change the behaviour of market actors.
And to do that, we need policies that provide economic incentives and make it logical for companies to invest and participate in the circular economy. Otherwise, behaviour will not change.
For example, we know that energy renovation of buildings is a key element of reaching global climate goals. And that too many of the world’s buildings are energy inefficient and will still be standing for many decades to come. We also know that municipalities tasked with handling and collecting waste are overburdened. According to C40 Cities, waste disposal is responsible for 3-5 percent of the overall direct GHG emissions in cities and those emissions are projected to increase substantially by 20504.
Legislation could take care of these challenges – setting requirements and/or providing incentives for companies to use durable and recyclable materials to renovate existing and construct new buildings and to increase landfill costs so recyclable material does not end up where it shouldn’t.
One of the main challenges of taking back products for manufacturing companies in general is the sorting and collection step. If this is not done properly, the material returned is mixed together with general waste from e.g. demolition sites.
At ROCKWOOL, we have been taking back stone wool for more than 30 years in some markets and have picked up a thing or two along the way. For instance, teaming up with local partners to facilitate an easy procedure for our customers to send back waste and ensure that our factories only receive high-quality material. We see ourselves as being part of a value chain, instead of a stand-alone activity.
In some cases, reclaimed material needs to be transported over long distances. Stone wool is a lightweight, voluminous material making it critical to fill up the trucks as much as possible to decrease costs and the carbon footprint of transportation. Technologies such as compacting and shredding enable us to continuously improve the efficiency of our take back operations and improve our reach.
Germany and Austria are among the top recycling countries in the world5 and have committed to ban landfilling of mineral wool (stone wool and glass wool), respectively in 2024 and 2027. These examples show that ambitious governments and local authorities can make a true mark on the environment by ensuring conducive regulation for a circular economy.
Although our products are made of stone, one of the most abundant raw materials on earth, a key part of ROCKWOOL’s operations is centred around increasing our use of non-virgin materials in our production. Besides taking back stone wool from the market via Rockcycle, we also recycle non-virgin materials from other industries such as slag from the steel industry. In 2024, 20.5% of the materials we used for our production were secondary / non-virgin materials.
Of the virgin resources consumed each year, roughly half is for the construction industry. In addition, the industry accounts for almost 40 percent of global CO2 emissions and solid waste streams6. This makes it a key sector to focus on when it comes to decarbonisation and waste reduction.
Architects, construction companies and other stakeholders are increasingly asking for ways to reduce waste at building sites and for a sustainable end-of-life alternative for construction materials. Recycling via Rockcycle can also act as documentation for green building schemes such as DGNB and Cradle to Cradle certification.
By taking a circular approach – where waste is designed out and resources are used efficiently – we can create an economy that is both sustainable and profitable. If the construction industry became more circular in its approach to waste, it could save more than two billion tonnes of CO2 by 20507. That’s equivalent to saving the CO2 generated by almost 400 million cars in one year!
In addition, there is also a large socio-economic benefit as 45 million waste management jobs could be created by 2030 in a circular economy and a whopping 103 million jobs through implementing the Paris agreement as well as the shift to sustainable production and consumption patterns[8],[9]
[1] Data- and stakeholder management framework for the implementation of BIM-based Material Passports (Data- and stakeholder management framework for the implementation of BIM-based Material Passports (sharepoint.com))
[2] Testing done at Danish Technical Institute (DTI) in 2023
[3] ROCKWOOL calculations
[4] https://www.c40.org/what-we-do/scaling-up-climate-action/waste-management/
[5] Recycling Rates by Country 2023 (worldpopulationreview.com)
[7] Applying principles of circularity to the built environment could reduce global CO2 emissions from construction and demolition of buildings by 2.1 billion tonnes, by 2050, making them vital to reaching net zero (Ellen MacArthur Foundation, 2021).
[8] International Labour Organization. (2018). World employment and social outlook 2018: Greening with jobs.
[9] International Labour Organisation (2022). https://www.ilo.org/wcmsp5/groups/public/---europe/---ro-geneva/---ilo-brussels/documents/publication/wcms_846882.pdf