Knauf Vidiwall 12.5 mm is a gypsum fibreboard manufactured from calcined gypsum reinforced with recycled paper fibres. It is designed for dry construction systems where robust, non-loadbearing linings are required. The boards are used for wall and ceiling linings on metal or timber frames and for fire-protective internal cladding. Mechanical performance is defined by high surface hardness and bending strength, supporting durable service in high-traffic interiors. Fire performance is classified as A2-s1,d0 to EN 13501-1, confirming limited combustibility. Boards can be cut, screwed or nailed using standard drylining tools and are compatible with Knauf proprietary systems and finishes. The material is dimensionally stable, moisture resistant for internal use, and suitable for long-term application. Environmental performance is documented through an EN 15804 compliant EPD covering cradle-to-gate impacts.