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‘A third of all waste in developed countries is construction waste. We have to do better!’


The Danish construction company CASA has made it their mission to take the lead in reducing the huge amount of waste generated by construction sites every day.

Rubble, plasterboard, wood, paint, chemicals and plumbing waste. The world’s construction sites are major sources of waste that far too often end up at incineration facilities or landfills rather than recycling centres. Even in Denmark, there is considerable lack of knowledge and coordination when it comes to handling the large quantities of waste generated by construction projects. This is what CASA is working to change, executive officer Michael Storgaard explains.

"There is probably no other industry where the need to reduce waste is greater than in the construction industry which we are part of. It involves not only the production phase, which generates huge amounts of waste, but also the operational phase, where there is still room for improvement. As a responsible industry, we need to optimize the use of resources and reduce our environmental impact."

As a general contractor, CASA does not have their own employees at the construction sites, but rather hire subcontractors for the different phases of the construction. According to Michael Storgaard, this system is the problem in a nutshell.

"Like most contractors, we hold our subcontractors responsible for the deliveries on site. When it comes to waste management, however, there are virtually no contractual obligations or central coordination. In practice, this means that the carpentry company disposes of the wood, the masonry company disposes of the rubble, the painting company disposes of paint residue and so forth. This system makes it difficult to control if waste is managed sustainably. We also miss out on the opportunity to share knowledge and to optimize across the value chain. The need for both documentation and transparency is thus evident."

To address these challenges, CASA has initiated a comprehensive mapping of the waste challenge in preparation for an implementable action plan, says Michael Storgaard.

"First, we need to get an exact overview of the different kinds of waste generated by the construction sites. Next, we need to focus not only on sorting but also on recycling, for example by returning wood, plasterboards and other residual products to the suppliers. Finally, we need to carefully analyse the resulting data. Most likely, we will need to rethink our material consumption in some areas altogether. These are the data we are now starting to retrieve."

Photo: CASA


Michael Storgaard acknowledges that CASA faces a comprehensive and challenging process in convincing all suppliers to get on board with the new initiatives.

"The construction industry is under extreme pressure in terms of pricing since customers expect high quality at a low cost. Frontrunners on sustainability and environmental responsibility therefore tend to struggle, as basic pricing mechanisms pull in the other direction. We are nevertheless committed to establishing a more transparent system, and want to consider our waste streams as resources that can be recycled with a financial gain. Our participation in the SDG Accelerator programme has given us an important push in that direction, including getting our employees, the real experts, on board. We in fact gathered all of our employees for a collective brainstorming facilitated by the SDG Accelerator team, which generated more than 200 specific ideas for how to achieve more sustainable construction sites."

In addressing these challenges, Michael Storgaard considers the Sustainable Development Goals vital resources for enabling transformation across businesses, including the construction industry.

"The climate debate has become a global movement, which is more than anyone would have imagined just five years ago. People demand action! Whether it be waste management, recycling or new, climate-friendly materials, we must meet customer demands for more sustainable solutions by bringing stakeholders together to close the knowledge gap within the industry. I am convinced this is the right way forward."

Read more about CASA here.

SDG 12.5

CASA aims at substantially reducing waste generation through prevention, reduction, recycling and reuse. Thereby, hoping to increase responsible consumption and production.


CASA has initiated an extensive plan to map and analyze the huge amounts of waste generated by construction sites every day.


The increased transparency caused by the data-collection is a first step to promote coordination, sorting, and recycling of waste, as well as an overall evaluation of material consumption.

Founded 2005

CASA A/S employs approximately 200 people.


CASA has offices in Søborg and Horsens, both Denmark.

Business model

CASA constructs and renovates all types of buildings, including shopping malls, office spaces, warehouses, logistics and production properties, parking garages, retail, and residential.