Zoning codes are a method that governments can use to regulate the development of private property. The two main purposes of zoning are to segregate different usage types into discrete areas and to help retain the character of existing communities by regulating any new construction. A zoning code may specify the way that real estate can be used, place limitations on buildings or other structures, or do both. The three main categories created by zoning codes are residential, commercial, and industrial, and there are also other special use zones. Zoning is typically the responsibility of local governments, though some countries have national regulations as well.
One of the main purposes of zoning codes is to separate various property uses that may be incompatible. This is one way residential neighborhoods, commercial districts, and industrial areas can be created. Properties of similar uses or densities are often grouped so that each property owner can get the best possible use out of his real estate. Density refers to how intensely a property can be used. Residential property that is zoned for light use will typically be limited to single family homes, while high density residential areas can include large condominiums or apartment complexes.
For commercial and industrial property, density will often relate to the types of businesses that are allowed to operate. Many areas have special restrictions on different types of commercial and industrial property that restrict the business types, so a low density commercial lot may be allowed to have a convenience store but not a car dealership. Zoning codes can also define building heights, lot coverages, and a variety of other factors depending on particular local ordinances.
If a zoning code is changed to a lower density, any existing use may be grandfathered in. This term essentially means that the existing use can continue as long as the current owner occupies the property or the business remains in operation. In other cases, a variance may be obtained to use property in a way that would not otherwise be permitted by a zoning code. Zoning codes will sometimes have specific use types that require variances.
In many cases, each local municipality is responsible for passing its own zoning ordinances. This allows each county, city, or town to define the way that the real estate within its borders will be developed. Some countries have national regulations, which may specify the way that zoning codes have to be drawn up. Local municipalities control their own zoning codes in many countries that have federal governments, but any property owned by the national government is exempt.