Which of the following is NOT a category of Class I construction?

Class I construction refers to a specific classification of buildings and structures that are typically characterized by their non-combustible materials and limited fire spread potential. This classification breaks down into various categories based on the weight and type of materials used in the structural components.

Class I heavyweight, Class I medium weight, and Class I lightweight all describe different variations of Class I construction depending on the thickness and density of the materials used. These distinctions are crucial for understanding the building's fire performance and how it will behave in a fire situation.

On the other hand, Class II subclass refers to a different classification of construction altogether. It indicates a building type that is not classified under Class I but rather suggests components capable of some combustibility or a mixture of both combustible and non-combustible materials. Thus, it does not fit within the categories defined under Class I construction. Understanding these classifications helps fire officers assess the fire risks and management tactics required for various building types.