An over-improvement occurs when the cost or quality of a property’s improvements exceeds what the market will typically support. This creates a disconnect between development cost and contributory value at resale.
A common example is a high-end kitchen renovation in a neighborhood of lower-priced homes, where buyers are unlikely to pay a premium that fully reflects the upgrade cost. In appraisal, over-improvements are generally treated as a form of functional obsolescence and may result in limited contributory value within the cost approach.
Over-improved properties can be more difficult to support with comparable sales and may present challenges in valuation and underwriting. In many cases, value is ultimately constrained by local market levels rather than improvement cost.