Hidden:Papers Turns Industrial Cardboard Waste Into Modular Furniture

Designer Raphael Klug has created a modular furniture system from discarded cardboard tubes. Called Hidden:Papers, the collection combines cardboard, linoleum and recycled plastic. It includes chairs, shelves and tables that users can take apart, repair and recycle.

From Waste To Furniture

Klug developed Hidden:Papers for his bachelor’s project at the Köln International School of Design (KISD). He graduated in February 2025. His background as a cabinetmaker helped him develop the system in just 12 weeks.

For the project, Klug chose a common material from industrial waste streams: cardboard. The tubes come from the plastics and textile industries. They offer strength, low weight, low costs and good recycling options.

However, cardboard also has some drawbacks. Moisture can damage it, while its surface often looks temporary or unfinished. For this reason, designers mainly use cardboard furniture for short-term settings. Furniture manufacturers also use cardboard as a hidden core beneath glued layers. These layers improve its appearance and durability, but make recycling difficult.

Klug wanted to bridge the gap between these two applications. His system keeps cardboard as the main structural material while adding a strong and attractive surface.

Linoleum Covers Without Glue

Coloured linoleum covers each cardboard tube. Klug connects the edges of the linoleum with paper cord. He then pulls the cover over the tube and stitches it closed under tension. The design uses no glue.

The linoleum gives the cardboard a durable surface and improves its appearance. Users can remove the cover by cutting the seam with a kitchen knife. They can then replace damaged linoleum or choose another colour. A five-millimetre Allen key allows them to take apart the rest of the furniture.

Recycled Plastic Connectors

Klug also designed 15 different connectors from recycled polypropylene. Manufacturers can produce these black parts through injection moulding and adjust their scale. The connectors join, extend or support the cardboard tubes. An expanding system grips each tube without damaging it.

The different connectors turn Hidden:Papers into a flexible furniture kit. Users can replace individual tubes, covers or connectors instead of throwing away the complete product.

The prototype series includes three pieces. The side table measures 490 by 400 by 400 millimetres. The chair measures 800 by 500 by 520 millimetres. Finally, the shelving unit measures 1,340 by 1,800 by 442 millimetres.

The Green Concept Award nominated Hidden:Papers in 2025. The project shows how simple joints and separable materials can give industrial cardboard waste a new role in circular furniture design.

Source: BauNetz / Raphael Klug
Photos: Manuel Meyer.