Introduction of building construction and what is building construction

Building Construction

2.1 INTRODUCTION

The National Building Code (NBC) of India defines a building as any structure for whatsoever

purpose and of whatsoever material constructed and every part thereof whether used as human habitat

or not. Tents, shamianas, tarpaulin shelters, etc., erected for temporary and ceremonial occasions are

not to be considered as buildings.

1. Classifications as per NBC of India

1. Group A : Residential

2. Group B : Educational

3. Group C : Institutional

4. Group D : Assembly

5. Group E : Business

6. Group F : Mercantine

7. Group G : Industrial

8. Group H : Storage

9. Group I : Hazardous

1. Residential buildings are subdivided as

A–1 : Lodging or rooming houses.

A–2 : One or two family private dwellings.

A–3 : Dormitories.

A–4 : Apartment houses

A–5 : Hotels

2. Educational Buildings

B–1 : Schools upto senior secondary level with not less than 20 students.

B–2 : All other training institutions upto 100 students.

3. Institutional Buildings

C–1 : Hospitals and sanatoria

C–2 : Custodian institutions

C–3 : Penal and mental institutions

4. Assembly Buildings

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 assembly of people not covered by D–1 to D–4, e.g., grand

stands, stadia, circus tents, amusement park structures.

5. Business Buildings

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

6. Mercantile Buildings

F–1 : Shops, stores, markets with area upto 500 m2

.

F–2 : Underground shopping centres, departmental stores with area more than 500 m2

.

7. Industrial Buildings

G–1 : Buildings used for low hazard industries.

G–2 : Buildings used for moderate hazard industries.

G–3 : Buildings used for high-hazard industries.

8. Storage Buildings

Buildings used for storing materials and animals such as warehouses, cold storages, freight depots,

garages, hangars and stables.

9. Hazardous Buildings

These are the buildings used for storage, handling, manufacturing or processing of highly

combustible or explosive materials. Buildings used for 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-storey 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.

• 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 a building 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 vertical distance between the centre line street in front and the highest point

of building including parapet at terrace. If building is sloping towards the street, the building height

is considered upto the point where the external wall touches the sloping roof. In case of gable

facing the street, it is considered upto the midpoint of gable end.

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

centre line of the street.

3. Setbacks 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 covered area or built-up area. It does not include well, storage tank, open verandah, portico,

ramp, steps, compound wall, watchman’s booth, uncovered staircase.

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

6. Floor-area-ratio (FAR)

FAR =

Important By-laws

1. Distances from power supply main

Distances from power supply main is shown in Table 2.1.

2. Exterior open spaces

(a) Minimum front open space As shown in Table 2.2.

Table 2.2 Minimum front open space

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 case of 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 required increases 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 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 2.3.

Kitchen Minimum size requirements of a kitchen are as shown in Table 2.4.

 

4. Bathroom and water closet At least one wall should abut the exterior open space. Should have

impervious floor and wall. Other requirements are shown in Table 2.5.

Table 2.5 Minimum requirement of bathroom and water closet

5. Storeroom In a residential building storeroom size shall not be less than 3.2 m2

. Minimum height

2.2 m.

6. Parapet 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 centre line of the front street. Upto 2.4 m also

permitted if the top 0.9 m is open type. In 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. Bed rooms–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 circulation area and if it is more than 1.5 it gives 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 kitchen, sanitary blocks should be close to bed-

rooms. In offices administrative block is located centrally.

6. Circulation Circulation refers to the space provided for movement. Passages, lobbies and wells

serve as horizontal circulation area, while stairs and lifts serve as vertical circulation area.

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 elegance of a building.

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

9. Flexibility A study room may be planned for using as guestroom; by providing partition, living

room and dining room may be utilized for family functions, whenever necessary. By providing

independent access to backyard from the kitchen, backyard can be used for hosting dinners.

10. Privacy By the proper grouping of rooms privacy of rooms from one to other and from outside

can be achieved.

11. Practical considerations Economy is major practical consideration. Future provisions should be

made to improve flooring, extending building and improving elevation without dismantling any part

of the building.

• Basic requirements of a building are strength and stability, dimensional stability, resistance to

dampness, resistance to fire, heat insulation, sound insulation, protection from termite, durability,

protection against burglary, lighting and ventilation, comforts and conveniences and economy.

• A residential building essentially consists of living, sleeping and service area. These areas should

be clubbed properly to get comfortable living condition.

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 building permission from competent authority notice for intended construction should be

given along with key plan in 1 : 10000 scale, site plan in 1:500 to 1 in 1000 scale, building plan in

1:100 scale along with elevation and sectional views. Fee receipt copy should accompany the

notice.