What is the value increase of combined properties over their original individual values called?

The value increase of combined properties over their original individual values is referred to as plottage. This concept is vital in real estate as it highlights how merging two or more adjacent parcels of land can create a more valuable property than if they were sold separately. The increased value can arise from a variety of factors, such as improved usability or the potential for development that wouldn't be feasible on the smaller, individual parcels.

In real estate transactions and appraisals, understanding plottage is essential for assessing the highest and best use of land. When properties are brought together, they might facilitate larger developments that attract more buyers or tenants, thereby driving up the overall worth of the combined properties. This is a key consideration for developers and investors looking to maximize their investments through strategic property acquisitions.

The other terms do not apply in this context; accession refers to the increase in property value or ownership due to natural or artificial growth, attachment generally relates to fixtures or improvements that are firmly affixed to a property, and exchange describes the process of trading properties rather than the increase in value of paired properties.