4. The parties also agree that there is a difference between functional obsolescence caused by a deficiency and functional obsolescence caused by a defect. A deficiency means the subject property is missing some machine or equipment (machine) and therefore incurs greater operating costs than a plant with that machine. A defect means that a machine in the subject plant is less efficient or more costly to operate than a machine performing an equivalent function in the modern plant. These definitions are consistent with the terms "deficiency requiring an addition" and "deficiency requiring substitution or modernization" contained in the 11th edition at pages 388 through 389.
The concept of "cost to cure" is largely undisputed by the parties. It is the cost that would be incurred in changing the subject property to correct the flaw. If the subject property suffers from a deficiency, the cost to cure would be: (1) the cost of the missing machine, and (2) the cost of installing that machine. The parties agree that installing a machine in an existing property may be more expensive than installing the same machine when a plant is constructed new. To the extent the cost is greater, it is referred to as "excess" cost.
If the subject property suffers from a defect, the cost to cure would be the total of: (1) the cost to remove the defective machine, (2) the remaining DRC of the defective machine (6) (less its salvage value), (3) the cost of the new machine, and (4) the cost of installing the new machine.
The dispute between the parties arises not so much from the concepts as from the calculations applying the concepts. That may be due to the fact that when calculating functional obsolescence, one is hypothesizing an addition in order to calculate a deduction. This mental gymnastic requires one to consider market motives while staying true to the assumptions of the cost approach. Because cost is used as a surrogate for value, calculations of functional obsolescence must relate to the cost of the subject property.
Confusion may also arise from imprecise application of the concepts. It is important to understand that cost to cure is not the same as functional obsolescence. The distinction is important because curing the flaw results in a different property than the subject property whose value is being determined.