TYPES OF BUILDINGS AS PER NBC – DESIGN, PLANNING, BUILT-UP AREA

TYPES OF BUILDINGS – AS PER NBC OF  INDIA

1. Residential
2. Educational
3. Institutional
4. Assembly
5. Business
6. Mercantine
7. Industrial
8. Storage
9. Hazardous

A–1: Lodging or rooming houses.
A–2: One or two-family private dwellings.
A–3: Dormitories.
A–4: Apartment houses
A–5: Hotels

B–1: Schools up to senior secondary level with not less than 20 students.
B–2: All other training institutions up to 100 students.


3. Institutional Buildings

C–1: Hospitals and sanatoria
C–2: Custodian institutions
C–3: Penal and mental institutions

D–1: Buildings with theatrical stage and fixed chairs for over 1000 persons.
D–2: Buildings having a theatrical stage and fixed seats for less than 1000 persons.
D–3: Buildings without a stage and having accommodation for 300 or more persons but without permanent seating arrangements.
D–4: Buildings without a stage, having accommodation for less than 300 persons.
D–5: All other buildings designed for the assembly of people not covered by D–1 to D–4, e.g., grandstands, stadia, circus tents, and amusement park structures.

The building is used as a shop, store, market for display, and sale.

F–1: Shops, stores, and markets with areas up to 500 m2
F–2: Underground shopping centers, departmental stores with areas more than 500 m2

G–1: Buildings used for low hazard industries.
G–2: Buildings used for moderate hazard industries.
G–3: Buildings used for high-hazard industries.

Buildings used for storing materials and animals such as warehouses, cold storage, freight depots, garages, hangars, and stables.

These are the buildings used for storage, handling, manufacturing, or processing of highly combustible or explosive materials.

Buildings used for the storage of LPG, rocket propellers, ammunition, explosives, and fireworks fall under this category.

2. Classification based on the method of load transfer According to this buildings may be classified as load-bearing structures and framed structures. Load-bearing structures are suitable for one- or two-story residential buildings only.

3. Classification According to materials Structures may be classified as wooden structures, R.C.C. structures, steel structures, etc.

4. Classification according to fire resistance NBC of India classifies buildings as Type 1 to Type 4 on the basis of fire resistance.

• The basic components of a building are Foundation, plinth, walls and columns, sills, lintels and sunshades, floors, roofs, steps, stairs, and ramps, finishing works, and building services.
• A structure should be designed to withstand various loads during its life span. IS 875–1987 gives the various loads to be considered.

 

 

Building Planning

• It refers to the process of imagining the details of building planning to be built and showing them in the form of drawings.

• The building by-laws are prescribed in IS: 1256–1967 and municipalities and other competent authorities have the power to make changes to suit local requirements. The laws are necessary to ensure orderly growth, afford safety against fire, noise, and health hazards, and give guidelines about minimum standards.

Terminology

1. Building height It is the vertical distance between the centerline street in front and the highest point of the building including the parapet at the terrace. If the building is sloping toward the street, the building height is considered up to the point where the external wall touches the sloping roof. In the case of the gable facing the street, it is considered up to the midpoint of the gable end.

2. Building line It is the least horizontal distance of the permanent portion of the building from the centerline of the street.

3. Setbacks are lines parallel to the boundaries of the site.

4. Covered or built-up area The area covered by the building immediately above the plinth level is called a covered area or built-up area. It does not include a well, storage tank, open verandah, portico, ramp, steps, compound wall, watchman’s booth, or uncovered staircase.

5. Floor area It is equal to the plinth area minus the area occupied by walls and columns.

6. Floor-area-ratio (FAR)

FAR = Covered area floors/area of a plot

Important By-laws

1. Distances from power supply main

Distances from the power supply main are shown in Table.

2. Exterior open spaces

(a) Minimum front open space As shown in Table.

SR NO	WIDTH OF STREET FRONTING	FRONT OPEN SPACE
1	UP TO 7.5M	1.5M
2	7.5 TO 18.0M	3.0M
3	18.0 TO 30.M	4.5 M
4	ABOVE 30 M	6.0 M

For building up to a maximum of 7 m.

(b) Rear open space: The minimum rear open space should be an average of 3.0 m and in no case less than 1.8 m. In the case of the back-to-back site, the rear open space should be 3.0 m throughout. For plots of depth less than 9 m and buildings of height less than 7 m, the minimum is reduced to 1.5 m

(c) Side open space: For detached buildings, the minimum open space recommended is 3.0 m on each side. However, for smaller plots, it may be reduced to 1.5 m by the competent authority. For buildings of height above 10 m, minimum rear, and side open spaces are required to increase with the height of a rule of 1 m for 5 m height. For buildings above 50 m high, it is 16.0 m.

3. Floor area ratio (FAR) It is different for different occupancy buildings.

4. Height of buildings The height and number of stories are related to the requirements of FAR and open space. It is also limited by the width of the street in front of the building. The height is limited to 1.5 times the width of the front road plus the front open space. The height of buildings in the vicinity of an airport is fixed in consultation with the civil aviation authority.

Other Requirements of Buildings

1. Plinth height It should be 0.45 m above the surrounding ground level. It should be at least 0.15 m above the nearest street.

2. Habitable rooms The requirements are shown in Table.

3. Kitchen Minimum size requirements of a kitchen are as shown in Table.

TYPE	MIN FLOOR AREA	MIN WIDTH	MIN HEIGHT
KITCHEN CUM STORE	5.0M2	1.8M	2.75M
KITCHEN CUM DINING	7.5M2	2.10M	2.75M
KITCHEN ONLY	4.5M2	1.8M	2.75

 

4. Bathroom and water closet At least one wall should abut the exterior open space. Should have an impervious floor and wall. Other requirements are shown in Table

minimum requirement of bathroom and water closet

	BATH	W.C	BATH CUM W.C
MIN FLOOR AREA	1.8 M2	1.2 M2	2.8 M2
RECOMMENDED SIZE	1.5 X 1.2 M	1.10 X 1.0 M	2.3 X 1.2 M
MIN.HEIGHT	2.0 M	2.0 M	2.0 M

 

5. Storeroom In a residential building storeroom size shall not be less than 3.2 m2. Minimum height of 2.2 m.

6. Parapet is Not less than 1.05 m high and not more than 1.2 m above the finished floor level.

7. Compound wall Maximum height 1.5 m above the centerline of the front street. Up to 2.4 m is also permitted if the top 0.9 m is open type. In the case of corner plots, the lower 0.75 m may be of solid type but the top 0.75 m should be open type at least for a distance of 10 m.

Elementary Principles of Planning

1. Aspects Kitchen-eastern aspect, Dining-southern aspect, Drawing and living rooms-Southern or South-eastern. Bedrooms–Western aspect.

2. Prospects It is about locating and selecting the type of doors and windows in the outer walls so as to reveal the pleasant features and hide undesirable features.

3. Roominess length to width ratio should be 1.2 to 1.5. If it is nearly square, there will be wastage due to the circulation area and if it is more than 1.5 it gives a tunnel effect.

4. Furniture requirement Position of chairs, sofas, tables, beds, wardrobes, etc., should be drawn and checked for circulation area.

5. Groupings A dining room should be close to the kitchen, and sanitary blocks should be close to the bedrooms. In offices, the administrative block is located centrally.

6. Circulation refers to the space provided for movement. Passages, lobbies, and wells serve as horizontal circulation areas, while stairs and lifts serve as vertical circulation areas. The circulation area should be least but sufficient also.

7. Elegance It refers to the effect felt by a viewer from outside. The width, length, height, balconies, and projection contributes to the elegance of a building.

8. Sanitation It includes good lighting, ventilation, and sanitary conveniences.

9. Flexibility A study room may be planned for use as a guestroom; by providing partition, the living room, and dining room may be utilized for family functions, whenever necessary. By providing independent access to the backyard from the kitchen, the backyard can be used for hosting dinners.

10. Privacy By the proper grouping of rooms privacy of rooms from one to another and from outside can be achieved.

11. Practical considerations The Economy is a major practical consideration. Future provisions should be made to improve flooring, extending the building, and improving elevation without dismantling any part of the building.

• The basic requirements of a building are strength and stability, dimensional stability, resistance to dampness, resistance to fire, heat insulation, sound insulation, protection from termites, durability, protection against burglary, lighting, and ventilation, comforts, and conveniences, and economy.

• A residential building essentially consists of a living, sleeping, and service area. These areas should be clubbed properly to get comfortable living conditions.

• The essential components of an industrial building are office, factory, godown, and other facilities. The other facilities include proper entrance, parking, cloakroom, drinking water, canteen, sanitary block, medical aid, loading, and unloading platform.

• To get types of buildings as per nbc permission from competent authority notice for intended construction should be given along with the key plan in 1:10000 scale, a site plan in 1:500 to 1 in 1000 scale, a building plan in 1:100 scale along with elevation and sectional views. The fee receipt copy should accompany the notice.