Zoning in Town Planning

1               zoning

           

1.1            General

Zoning is the application of common sense and fairness to public regulation governing the use of private land. Zoning can be defined as the creation by law of the zones such as residential, commercial, industrial, civic, institutional and recreational in which regulations prevent misuse of lands and buildings and limit their height and densities of population differing in different zones. While planning a city the area of town can be divided into following zones:

1.      Industrial zone

2.      Administrative zone

3.      Business zone

4.      Open space

5.      Residential zone

a)      Different zone for different height

b)      Zone for single family

c)      Zone for two family

d)     Zone for apartment houses

6.      Recreational zone

7.      Local administrative zone

8.      Agricultural zone.

Zoning sets apart different areas in the town for specific purposes. It prevents encroachment of one zone upon another adjacent to it.

1.2       Objects of Zoning

The objects or purposes of zoning are as follows:

1.      To lessen congestion in streets.

2.      To secure safety of fire and other hazards.

3.      To promote health and general welfare.

4.      To provide adequate light and air.

5.      To protect the value of property.

6.      To prevent over-concentration of population.

7.      To facilitate transportation, water supply, sewerage, schools, parks, etc.

8.      To encourage the most appropriate use of land.

1.3       Principles of Zoning

The main principles of zoning can be briefly summarized as follows:

1.      Arrangement of zones: The usual pattern of zones is in central area, and undeveloped area. The other pattern of zones would be to provide blocks or units for various uses in different parts of the town.

2.      Boundaries: The design of boundaries for different zones should be carefully made. A railway line or a park or an open green space may prove to be satisfactory boundary.

3.      Existing towns: When zoning is to be applied to an existing town, the information regarding the existing use of land is gathered and as far as possible, the town is divided into zones by considering the pre-dominant use in the particular areas.

4.      Flexibility: The principles of zoning may be rigidly enforced. But at the same time, care should be taken to observe flexibility in working out the details for zoning. For instance, homes should be very near to places of work to reduce time of travel. Similarly, the small shopping centres for day-to-day requirements should be allowed in residential zone.

5.      New towns: For designing a new town of known population, the areas required for residence, industry and business are worked out with the help of suitable methods. The town is divided into suitable zones.

1.4       Advantages of Zoning

Following are the advantages of zoning:

1.      Business or commercial areas are separately located with their garages and service stations at a distance from the residential areas.

2.      The industrial area is located away from the residential area so it is not affected by dangerous gases, smoke, etc.

3.      The population is distributed throughout the town by zoning, so there will be no concentration of population in any one particular zone.

4.      Height zoning regulates the height of the buildings. Hence high rise buildings will not be allowed to construct near small houses.

5.      The zoning permits the economic use of various public utility services such as water supply, drainage lines, and telephone lines, etc.

6.      A land in the form of recreational area is provided to use as playgrounds, stadiums, parks, talkies, etc.

7.      Zoning promotes health, safety, prosperity, orderly development and overall welfare of community.

8.      The zoning results into minimum chances of fire occurrence.

9.      If zoning is adopted, it results into controlled future development of the town.

1.5       Densities of a Town

1.      Overall town density = Total population / Total town area

2.      Developed area density = Total population / Total developed area

3.      Gross residential area density = Total population / Total residential area

4.      Net residential area density = Total population / Net residential area

5.      Accommodation density = Number of habitable rooms / Area

6.      Occupancy rate = Number of persons / Number of habitable rooms

7.      Floor Space Index = Total built up area / Plot area

1.6       Aspects of Zoning

1.      Density zoning:

·         In density zoning, the density of population in the residential areas is controlled by means of suitable rules and regulations.

·         The density of population per unit area may either be expressed as gross density or net density.

·         The gross density is the average density of population per unit area of the whole area.

·         The net density is defined as the average density of population per unit of the housing area, including local roads only, excluding open spaces, public institutions, shopping centres, etc.

The following are the indirect measures adopted to have effective density zoning:

a)      The front, side, and rear margins from the boundaries are specified.

b)      The maximum height of the building is specified.

c)      The minimum size of allotment for each house is specified.

d)     The number of houses per unit area is limited.

e)      The ratio of total site area to the total built-up floor area is specified.

The advantages of density zoning are as follows:

a)      It promotes healthy conditions, as population is distributed throughout the town.

b)      It prevents over-crowding.

c)      It facilitates the proper layout and designing of various public amenities and services.

d)     The land values are stabilized.

e)      It ensures enough light and ventilation to the residences.

2.      Height density:

·         The main objects of height zoning are as follows:

                                                                               I.            To supply enough daylight to the buildings

                                                                            II.            To cause reasonable traffic movement.

·         It aims to control the height of buildings with due consideration of the following:

                                                                               I.            Bulk and cubical contents of the buildings

                                                                            II.            Street width and other adjacent marginal open spaces.

·         Due to height zoning, there is considerable setback in the design of high rise buildings or skyscrapers.

·         The restriction on the height of buildings will depend on nature of building, type of zone and climatic conditions.

Advantages of height zoning are as follows:

a)      It does not allow tall buildings to come up nearby smaller buildings.

b)      It establishes minimum standards in terms of light, air and space, thereby creates healthy conditions.

c)      It controls the setback from roads.

d)     It helps to construct the buildings with uniform height, which gives aesthetic appearance.

e)      It controls the land values.

3.      Use zoning:

·         The main principle of use zoning is to divide the city into different zones, in correct location with respect to the others.

·         It avoids the encroachment of one zone upon another adjoining it.

·         Utilization of each zone according to the purpose for which it is allocated.

·         Factories and industries on the residential areas can be completely avoided.

·         This zone provides open spaces, privacy and good health for the inhabitants of the town.

·         It results into stabilization of land values.

·         It provides better traffic facilities, water lines, sewer lines and use of other public utility and amenities in an efficient way.

Under the Use zoning the town is divided into the following:

a)      Residential zone: This is very important zone of the town, where the people of the town live together in large number. This zone covers an area of 40% - 50% of total land. The buildings coming under this zone are single family houses, semi-detached houses, group housing, chawl, flats, sky-scrappers, etc. The following are the points considered while locating residential zones:

·         Near to the market, free from noise and smoke, parks and playgrounds should be close by.

·         It should have certain amount of privacy and separated from other zones by wide strip of green belt which may consists of parks and parkways, etc.

·         Speedy travel and communication facilities.

·         Peaceful surroundings, as far as possible from industries and business zones.

·         Healthy environment with respect to hygienic and sanitary requirements.

b)      Industrial zone: This zone covers an area of 5% - 20%. This is next to the residential zone in terms of importance. Hence great care should be exercised in locating the industries. The following are the points considered while locating industrial zones:

·         Minor industries like bakeries, dairies, laundries may be grouped and located close to the residential zone for the benefit of inhabitants.

·         Light industries and factories like manufacture of glass, porcelain, and ice, etc. which use only electric power can be located anywhere on the periphery of the town.

·         Heavy industries giving out obnoxious (or harmful) gases and the industries causing noise such as manufacture of cement, steel, and other such material should be located on the outskirts of the town.

·         The special industries producing undesirable trade wastes and by-products may be located far away from town in spacious grounds.

c)      Commercial zone: This zone covers an area of 2% - 5%. This zone consists of markets, banks, ware-houses (gowdons), business offices. These should be located near centres of traffic and as far as along the road-sides.

d)     Civic zone: This zone covers an area of 2% - 3%. This contains all public buildings like town hall, court, public libraries, post office, museum, auditorium, bank, show-rooms, stores and houses for the employed under the government.

e)      Institutional zone: This zone covers an area of 1% - 2%. This zone contains schools, colleges, institutions, etc.

f)       Recreational zone: This is planned in the remaining area of the town, usually 15% - 20%. This is an important zone since it provides healthy environment for the people. It mainly includes parks, playgrounds, stadiums, cinemas, community centres. Generally, the various units of recreational zone are scattered throughout the town.

Reference:

·         Town Planning by Rangwala. Published by Charotar, 24^th edition; 2011.

·         Principles and Practice of Town and Country Planning by Lewis Keeble. Published by The Estates Gazette Ltd., London; 1959

·         Town Planning text book by H.S. Vishwanath, Published by Sapna book house, 2^nd revised and enlarged edition; 2014.