Circular plastic window frames made of 100% recycled material

From idea to reality, always one step further in sustainability

The ultimate circular choice. The ReFrame profile from profine, the company behind plastic window frame brand K-VISION, is synonymous with a completely closed material cycle. No new fossil raw materials are used for production. Each recycled gram of plastic reduces the use of mineral oil and energy. In addition, significant savings are made in transport and associated CO2 emissions, while the circular window profile has exactly the same technical properties as a "virgin" profile. That this is appreciated by the market is proven by the many partner companies, which have resolutely chosen ReFrame since its introduction in 2020.

One company that co-founded ReFrame is the North Holland family business Schipper Kozijnen. "Our relationship goes back more than 40 years," says Head of Sales Business Market Jappe Dekker. "As a frame manufacturer, we invariably assemble our plastic frames, windows, doors and sliding doors from K-VISION profiles. When special solutions are desired, Profine actively thinks along with us. Moreover, we are closely involved in developments and innovations. ReFrame is a great example of this."

Sustainability and circularity

The seed for ReFrame was laid in 2018, during a company visit with DOOR architects to the profine factory in Berlin. "DOOR architects, like profine and Schipper Kozijnen, is highly committed to quality, sustainability and circularity," said Dekker. "For example, in the past we gave several profine plastic window frames a second life in DOOR architects' company building in Amsterdam. Since then, we regularly spar about these themes. How nice would it be - in addition to one-to-one reuse - to also work with recycled material? For example, for the production of new window frames?" 

The main purpose of the visit to the Profine factory was to take the architects through the plastic window frame process, he says. "What does it take to make a special profile or special color? And what circular options are already available?"

First projects

"A special department has been set up in our factory, where profiles are coated with our revolutionary proCoverTec color coating," says Remco van Overdijk, technical-commercial account manager at profine Netherlands. 

"During the company visit by Schipper Kozijnen and DOOR architects, profiles were treated with a recycled core. With a question from the architects about the possibility of also making complete window frame profiles from recycled material, an interesting innovation and testing process began." 

Dekker: "We had large numbers of sample pieces developed and evaluated, to discover whether 100% recycled material is even technically feasible. What does this mean for production and assembly? And what will the window frame look like in this case? We made several mock-ups and shared them with DOOR Architects, contractor Hemubo and housing corporation Intermaris, among others. For example, for the renovation of four apartment buildings in the Wheermolen-Oost district of Purmerend. The test pieces were received very enthusiastically. Because this project was still in the tender phase, however, we renovated 105 apartments at Osdorpplein in Amsterdam as a pilot project, in collaboration with Hemubo and housing corporation Stadgenoot. Meanwhile, the first two flats in Purmerend have also been fitted with the circular ReFrame profile. A third apartment building will soon follow." 

The apartment buildings in Purmerend already contained window frames from Schipper Kozijnen and Profine. Van Overdijk: "These window frames have been and will be removed after forty years and recycled at a high quality, thus completely closing the chain."

Very stable

"By choosing 100% recycled material, the technical properties do not change significantly, with the exception of UV resistance," Van Overdijk says. "To overcome this and guarantee the usual high-quality properties and long service life, the profiles are treated all around with proCoverTec. For correct and easy processing and assembly of the profiles, we have inventoried possible optimizations together with Schipper Kozijnen. Also with regard to the product composition." 

Dekker: "Initially, the basic colors of the recycled plastic varied considerably, but now such 'start-up challenges' have been cleverly overcome. ReFrame has undergone tremendous development, so the profile is now very stable." 

Van Overdijk: "Meanwhile, the frame profiles can be routed through production in the usual way. Moreover, the circular profile has exactly the same technical properties as a 'virgin' profile, while saving substantially on raw materials, transport and CO2 emissions."

Fully closed material cycle

Anno 2022, more and more clients, architects and contractors are paying attention to sustainability and circularity. Not surprising, according to Dekker, because our raw materials are becoming increasingly scarce. Moreover, circular construction makes an important contribution to reducing our waste mountain and CO2 emissions. 

"As an organization, we go along with this by carefully dismantling old plastic window frames. Glass, panels, frames and hardware are carefully separated for reuse or recycling." 

Van Overdijk: "Window frames and hardware are stored in a 40m3 Profine waste container. At our plant in Berlin, the old window frames are then processed into granulate, which we reuse as a raw material. The same applies to saw waste and leftover pieces from plastic window frame production. At profine, no plastic fiber is thrown away or downgraded; a true closed loop, in other words."

The frame profiles and intermediate posts were still produced from 100% virgin material in recent years, Van Overdijk says. "Before the end of this year, we will also change this. Then both profiles will also be available with a recycled core, which means that more than 50% of the profile will consist of recycled content. That's how we keep going one step further in sustainability."