Which area corresponds to the coverage of insulation in the walls?

The coverage of insulation in the walls corresponds to the Insulation Area. This area specifically refers to the portions of the walls that require insulation materials for thermal resistance and energy efficiency. Insulation plays a crucial role in maintaining comfortable interior temperatures and reducing energy consumption.

To understand why this is the fitting choice, it's important to recognize that other areas listed do not define the specific coverage needed for insulation. The Gross Area typically refers to the total surface area of the building without consideration for specific applications like insulation. The Eaves Area pertains more to the roof's overhanging edges rather than wall insulation. Baseboard Length, on the other hand, relates to the linear measurement of baseboards at the bottom of walls, not to the insulation coverage itself.

Thus, the Insulation Area is the most appropriate designation for the element of building design that deals with the coverage required for adequate wall insulation.