Clay panel or clay board (also known as loam panel, clay wallboard, clay building board, clay building panel) is a panel made of clay with some additives. The clay is mixed with sand, water, and fiber, typically wood fiber, and sometimes other additives like starch. Most often this means employing the use of high-cellulose waste fibres. To improve the breaking resistance clay boards are often embedded in a hessian skin on the backside or similar embeddings.