Which term describes any physical change made on a structure to increase its value and aesthetic quality?

The term that best describes any physical change made to a structure to enhance its value and aesthetic quality is renovation. Renovation typically involves updating or improving a space, often with the intention of making it more appealing or functional. This process may include a variety of enhancements, such as modernizing fixtures, improving layouts, or adding new features that elevate the overall design and utility of the building.

In contrast, while repair refers to fixing something that is broken or deteriorating, renovation goes beyond to transform a space. Conversion usually means changing the intended use of a building, such as turning a warehouse into apartments, which does not inherently focus on aesthetic improvements. Alteration may involve modifications to the structure but doesn't explicitly convey the enhancement of value and aesthetics in the same manner as renovation. Therefore, renovation is the most fitting term for changes aimed at boosting both the value and the visual appeal of a structure.