Local zoning laws are a relatively recent development in our country’s history. The first comprehensive zoning legislation was enacted in the United States during the first third of the 20th century, with many zoning ordinances created in the period between 1940 and 1960. Before then, land use was largely unregulated, with different and often conflicting uses cropping up in the same area.
With the establishment of zoning, many uses that predated zoning ordinances now failed to conform to the new ordinance requirements. Commercial uses ended up in residential districts, and vice-versa. Many existing structures violated setback and yard size requirements. Are these uses and structures now illegal?
As a matter of constitutional law, older buildings and uses could not be forced to conform to the new zoning ordinances. After all, they were there first. They are deemed “grandfathered” – that is, they are considered lawful nonconforming structures and uses. Nonconforming uses are subject to certain special rules, however. Most zoning ordinances allow nonconforming uses to continue only if they are not discontinued for an extended period. If a nonconforming use is “abandoned,” it is lost and the property must be brought into conformity with the zoning ordinance. Many ordinances create a presumption of abandonment if the use is discontinued for a period of one year or more.
Nonconforming uses must also be allowed to expand reasonably, even if expansion increases the nonconformity with the zoning ordinance. Many ordinances limit this expansion to 25% of the nonconforming structure or use.
So if you are wondering how that old house got built so close to the road in a commercial zone, chances are it was there first – and continues as a lawful nonconforming use. As long as it is not abandoned it can be continued and even expanded within reason.
— Kevin Palmer