What is the area covered by the 4" insulation after accounting for openings referred to as?

The area covered by the 4" insulation after accounting for openings is referred to as the Insulation Area. This term specifically denotes the effective area where insulation is applied, not including any areas that are obstructed or where insulating material cannot effectively provide thermal resistance, such as openings for vents, electrical fixtures, or other penetrations. By focusing on the Insulation Area, one can accurately assess the amount of insulation needed and its potential performance in terms of energy efficiency.

The other terms, while related to the context of building architecture or insulation, do not specifically designate the area of insulation after accounting for openings. Gross Area usually refers to the total area of a space before considering any deductions, such as for openings. Eaves Area would pertain to the area around the edges of the roof, and Attic Space Area generally denotes the entire volume of the attic regardless of insulation placement. Thus, Insulation Area is the precise term for the effective area that insulation occupies in relation to thermal efficiency.