A Texas municipality enacts an ordinance requiring all new residential construction to have a minimum lot size of 10,000 square feet. A landowner with a 6,000 square foot lot that was legally built upon before the ordinance seeks to add a room. This is an example of:

Explanation

A nonconforming use (or nonconforming lot/structure) existed legally before a new zoning regulation was enacted. Texas municipalities generally allow nonconforming uses to continue but may restrict their expansion. The landowner may need a variance to add the room.