The Czech door manufacturer SAPELI introduces the Nanoverde doors made from recycled beverage cartons

"The Nanoverde doors are one of our initiatives through which we actively contribute to reducing environmental impact and upcycle material that is 80 percent ending up in incinerators," says SAPELI's sales director Marek Sedlák, adding: "In addition to the ecological aspect, we were also interested in finding alternatives to traditional materials like chipboard, and recycled beverage cartons proved to be a good choice. The resulting material is durable, strong, and offers excellent soundproofing, thermal insulation, and fire-resistant properties. Because of this, doors made from beverage cartons can fully compete with traditional ones." However, from a practical solution, it soon became a design issue at SAPELI - the recycled beverage carton is visually unique, and similar doors have no equivalent on the market. "We want to appeal to customers who care about both design and ecological responsibility," says Marek Sedlák.

How are Nanoverde upcycled doors made?

In developing the Nanoverde doors, SAPELI partnered with South Bohemian innovators from Flexibau, who hold the European patent for the technology of recycling beverage cartons and produce construction boards from them. To produce the surface of one set of Nanoverde doors, approximately 1000 beverage cartons are needed, with up to 90% made from used containers and the remaining 10% from previously recycled boards, known as returnable.

The material undergoes thorough cleaning, is then ground into small pieces, which are further subjected to separation and drying, and then pressed into compact boards at high temperatures using a binder, which is also made from used beverage cartons. "Unlike paper mills that only recycle the paper part, we are the only ones in the Czech Republic able to use the entire packaging including the polyethylene and aluminum layers, which we utilize as the binder," explains Erik Jakubec from Flexibau. The resulting board from the cartons is non-toxic and recyclable.

The frame of the Nanoverde doors is made from spruce wood sourced from sustainable forestry, and the filling consists of flax shives - a byproduct of flax processing. This material has good thermal insulation properties due to its density and structure and has better sound dampening capability than conventional fillings made from traditional materials. The Nanoverde doors retain the natural appearance of recycled material, and for atypical orders, SAPELI will offer the option of colored staining, allowing customers to obtain doors in various shades.

After beverage cartons, hemp is being tested

Research and development of sustainable materials at SAPELI does not stop at beverage cartons. "We are still looking for new alternative materials that are environmentally friendly. In the past, we tested e.g., fillings made from PET bottles or packaging materials from mycelium, that is, fungal mycelium. Currently, we are focusing on boards made from hemp. Our goal is to find materials that are not only ecological but also suitable for mass production; only then can we achieve a real reduction in ecological load," states Tomáš Albrecht, product development and marketing manager.

The group increases renewable energy sources

At SAPELI, sustainability in production itself is also being addressed. Roof-mounted solar power plants with a total output of over 1,000 kWp, along with battery storage with a capacity of nearly 2,500 kWh, have been installed at two company sites, which have been involved in providing balancing power services for ČEZ since the beginning of 2025. These installations cover approximately 40% of the electricity consumed at each site. Additionally, heating is provided by a proprietary cogeneration unit with an output of 200 kWe, which covers 60% of the total heat consumption and another 20% of the total electricity consumption, while the wooden waste from production is processed by a company producing chipboard located directly across from SAPELI. Last year, SAPELI fully transitioned to water-based ecological paints in production.

New product 2025: NANOVERDE

Technical specifications

• Full and glazed models of doors
• Door surface finished with natural oil Clear - high surface resistance
• Edges - made from natural veneer (classic and layered) or exclusively from aluminum
• Glazing frames - solid or with veneered surface
• Height of doors up to 250 centimeters, width up to 110 cm
• Ecological filling made of 100% natural flax
• Glass in glazed models as per choice
• Designs include classic rebated, but also flush, reversible, or sliding
• Price starting at CZK 14,990 excluding VAT

www.sapeli.cz