Definition and Classification of Buildings
As per the National Building Code of India (SP: 7–2005), a building is defined as any type of structure, constructed from any materials, intended for any purpose. This includes every component of the structure, whether it is used for human habitation or not. The term encompasses foundations, plinths, walls, floors, roofs, chimneys, plumbing, and various building services. It also includes fixed platforms, verandahs, balconies, cornices, projections, or any element affixed to the structure, such as walls enclosing land or space, as well as signs and outdoor display structures. However, temporary structures like tents, shamianas, and tarpaulin shelters are not considered buildings under this definition.
The National Building Code of India (2005) classifies buildings based on their occupancy into the following categories:
- Group A: Residential buildings
- Group B: Educational buildings
- Group C: Institutional buildings
- Group D: Assembly buildings
- Group E: Business buildings
- Group F: Mercantile buildings
- Group G: Industrial buildings
- Group H: Storage buildings
- Group I: Hazardous buildings
Group A: Residential Buildings
Residential buildings are structures designed to provide sleeping accommodations for regular residential use, which may or may not include facilities for cooking, dining, or both. However, buildings classified under Group C (Institutional Buildings) are excluded from this category. Group A is further divided into the following sub-categories:
A-1: Lodging or Rooming Houses
This category includes buildings or groups of buildings, managed by a single entity, where sleeping accommodations are provided for up to 15 individuals, either on a temporary or permanent basis. These accommodations may or may not include dining facilities but do not have individual cooking facilities. If a lodging or rooming house functions as a private dwelling, it falls under Subdivision A-2, provided that no more than three people occupy any single room.
A-2: One or Two Family Private Dwellings
Private dwellings under this category are occupied by members of a single family, offering sleeping accommodation for up to 20 individuals. If rooms are rented to external occupants, the limit is three persons per room. If the accommodation capacity exceeds 20 individuals in any one residential building, the structure should be classified under Subdivisions A-3 or A-4, depending on the specific case.
A-3: Dormitories
Dormitories consist of buildings that offer group sleeping accommodations in one room or a series of closely connected rooms, all under a single management. These accommodations are typically not for family members. Examples include school or college dormitories, hostels, and military barracks. Dining facilities may or may not be provided.
A-4: Apartment Houses (Flats)
Apartment houses are buildings or structures where living quarters are provided for three or more families, each living independently with separate cooking facilities. Examples include apartment complexes, mansions, and chawls.
A-5: Hotels
This category includes buildings or groups of buildings managed by a single owner that offer sleeping accommodations for more than 15 guests who stay temporarily. These places may have dining facilities, but it’s not required. Examples are hotels, inns, clubs, and motels, which primarily serve people who are visiting for a short time.
Group B: Educational Buildings
This group encompasses buildings used primarily for educational purposes, such as schools, colleges, and day-care centers. These structures are designed to accommodate assemblies for instruction, education, or recreational activities for a duration exceeding eight hours per week. Buildings in this category are distinct from those classified under Group D (Assembly Buildings).
Group C: Institutional Buildings
Institutional buildings are designed to serve those in need of medical care, treatment for mental or physical illnesses, or individuals under custodial or correctional care. These buildings often provide sleeping accommodations for their occupants, as they cater to people requiring extended stays, such as those in hospitals or correctional facilities. The liberty of some occupants, particularly in penal institutions, may be restricted. This group is further categorized into the following sub-divisions:
C-1: Hospitals and Sanitaria
This category includes buildings or complexes, managed as a single entity, where individuals suffering from physical or health issues are housed. Examples include hospitals, infirmaries, sanitaria, and clinics.
C-2: Custodial Institutions
This sub-division refers to facilities managed to provide care and custody for vulnerable individuals, such as children, the elderly, and convalescents. Examples include homes for the aged, infirmaries, orphanages, and convalescent homes.
C-3: Penal Institutions
These are buildings or complexes, managed as a single entity, used to house individuals under legal restraint or detention for penal or correctional purposes. Examples include jails, prisons, reformatories, and mental institutions where liberty is restricted for the inmates.
Group D: Assembly Buildings
Assembly buildings are designed to accommodate gatherings of people for various social, recreational, religious, or civic activities. These spaces serve as venues for events such as performances, exhibitions, dining, and public transportation services. Examples include theatres, auditoriums, museums, restaurants, places of worship, passenger terminals, and sports stadia. The sub-categories under Group D are as follows:
Sub-division D-1
This category includes buildings primarily intended for theatrical or operatic performances and exhibitions, equipped with a raised stage, proscenium curtain, lighting, motion picture booths, and other theatrical accessories. These buildings provide fixed seating for more than 1,000 people.
Sub-division D-2
This sub-division includes buildings designed for theatrical or operatic performances similar to those in Sub-division D-1, but with fixed seating for less than 1,000 people.
Sub-division D-3
Buildings in this sub-division are primarily intended for the assembly of people, such as dance halls, nightclubs, lecture halls, and museums. These buildings may have a raised platform but lack theatrical stages or cinematographic accessories. They typically accommodate over 300 people and may include spaces like passenger terminals and educational venues used for less than eight hours a week.
Sub-division D-4
This sub-division includes buildings similar to those in D-3, but with a smaller capacity, accommodating less than 300 people.
Sub-division D-5
This category covers outdoor assembly spaces not classified under D-1 to D-4. Examples include grandstands, amusement park structures, reviewing stands, and circus tents.
Group E: Business Buildings
Business buildings are structures designed primarily for conducting various commercial activities, excluding those categorized under Group F. These buildings serve as spaces for business transactions, record-keeping, and professional services. Common examples include offices for accountants, doctors, and dentists (unless categorized under Group C), as well as service facilities like newsstands, small lunch counters serving fewer than 100 people, barber shops, and beauty parlors.
Additionally, public administration buildings such as city halls, town halls, courthouses, and libraries fall under this category when their primary function is the transaction of public business or maintaining records and books.
Minor office spaces that are part of larger operations should be classified based on the primary use of the building under the relevant group.
Group F: Mercantile Buildings
Mercantile buildings encompass structures or parts of structures used for the display and sale of goods, whether for wholesale or retail purposes. These include shops, stores, and markets where merchandise is offered for purchase.
Facilities such as offices, storage areas, and services that are directly linked to the sale of merchandise and located within the same building are also classified under this group.
If a building is primarily used for another purpose but includes minor retail or merchandising activities, it should be classified according to the primary use of the building.
Group G: Industrial Buildings
Industrial buildings include structures or portions of structures where products or materials of various types are fabricated, assembled, or processed. This category covers a wide range of facilities, such as assembly plants, laboratories, dry cleaning establishments, power plants, pumping stations, smokehouses, gas plants, refineries, dairies, and sawmills.
These buildings are essential for activities that involve manufacturing or processing goods, often requiring specialized equipment and facilities.
Group H: Storage Buildings
Storage buildings refer to structures or parts of structures primarily used for the storage or sheltering of goods, merchandise, vehicles, or animals. These may also involve incidental activities such as servicing, processing, or repairs. Examples include warehouses, cold storage facilities, freight depots, transit sheds, storehouses, truck and marine terminals, garages, hangars (excluding aircraft repair hangars), grain elevators, barns, and stables.
This group excludes buildings used for the storage of highly combustible or explosive materials
Group I: Hazardous Buildings
Hazardous buildings are those structures or parts of structures utilized for activities involving the storage, handling, manufacturing, or processing of materials that are highly combustible, explosive, or present significant risks. These risks may include rapid combustion, the production of poisonous fumes, explosive reactions, or dangerous gases. Hazardous buildings may also handle materials that are corrosive, toxic, or produce flames, fumes, or gases that are irritant or corrosive. Additionally, they can involve the processing of substances that result in fine particles prone to spontaneous ignition.
Common examples include facilities used for:
(a) Storing gases such as acetylene, hydrogen, ammonia, chlorine, phosgene, sulphur dioxide, and others that pose risks of explosion, toxic fumes, or pressure hazards (over 0.1 N/mm² and exceeding 70 m³ in quantity);
(b) Storing and handling highly flammable liquids;
(c) Storing and handling hazardous, highly flammable, or explosive materials aside from liquids;
(d) Manufacturing items like artificial flowers, synthetic leather, ammunition, explosives, and fireworks.
Frequently Asked Questions
According to the National Building Code of India, buildings are classified into nine main types based on their occupancy:
- Group A: Residential Buildings
- Group B: Educational Buildings
- Group C: Institutional Buildings
- Group D: Assembly Buildings
- Group E: Business Buildings
- Group F: Mercantile Buildings
- Group G: Industrial Buildings
- Group H: Storage Buildings
- Group I: Hazardous Buildings
A building is any structure constructed for various purposes, including residential, commercial, or institutional use. It includes all components such as walls, roofs, foundations, and projections. The types of buildings, as classified by the National Building Code of India, range from residential to hazardous buildings, based on their intended use.
A museum is classified under Group D: Assembly Buildings, specifically Sub-division D-3. This sub-division includes buildings intended for the assembly of people for purposes like exhibitions, lectures, and other public gatherings.
The different types of buildings as per the National Building Code of India include:
- Residential Buildings
- Educational Buildings
- Institutional Buildings
- Assembly Buildings
- Business Buildings
- Mercantile Buildings
- Industrial Buildings
- Storage Buildings
- Hazardous Buildings
These types are categorized based on the use and function of the building.
A hotel falls under Group A: Residential Buildings, specifically Sub-division A-5. Hotels provide temporary sleeping accommodations for more than 15 guests and may or may not include dining facilities.
