What is the term for the protective covering used under stairs in accessible spaces?

The term for the protective covering used under stairs in accessible spaces is 1/2-inch gypsum board. This material is commonly used in construction due to its fire-resistant properties, which help to enhance safety in areas where access is necessary. Gypsum board is typically used in places where a protective barrier is needed to prevent the spread of fire and to improve structural integrity.

Using 1/2-inch gypsum board ensures compliance with building codes that often require fire-resistant materials in accessible spaces because these areas are not only meant for entry but also require enhanced protection for individuals, particularly in the case of a fire or other emergency. This material provides a smooth and sturdy surface while fulfilling safety regulations.

Plywood panels may not provide the same level of fire resistance and are typically used for different applications. Similarly, while 1/2-inch drywall is very similar to gypsum board, the specific term used in construction standards often points specifically to "gypsum board," which is a more precise term. Reinforced concrete is too heavy-duty and typically used for structural elements rather than for covering in accessible spaces.