Contiguous lots refers to lots that are adjacent to each other. People who want a larger parcel on which to build buy two or more lots that are side by side to increase the yard size. In the case of commercial development, developers assemble a series of contiguous lots to put up large structures. In larger urban areas, older neighborhoods may have more desirable locations where the housing is old and the lot is worth more than the structure. Sometimes people buy these properties and demolish the existing structures in order to build a new home in a central location. Commercial developers do the same too, and both new residential and commercial development in aging neighborhoods helps revitalize the area. In almost all jurisdictions, building on adjacent lots involves rezoning the property for the intended use. The second step requires working with the planning department to be certain that the planned structure meets the building code requirements and zoning stipulations.