General building requirements refer to the minimum standards and guidelines for the various elements and spaces within a building, including habitable rooms, kitchens, bathrooms and water-closets, ledges or lofts, mezzanine floors, store rooms, garages, basements, chimneys, parapets, cabins, boundary walls, wells, office-cum-letter box rooms, meter rooms, and roofs.
These requirements are established by local and national building codes and regulations, and they dictate the design and construction standards for these spaces, including aspects such as size, accessibility, fire safety, energy efficiency, ventilation, and plumbing.
The requirements for various parts of buildings as per NBC. shall be in accordance with given below.
For Main Buildings
The plinth or any part of a building or outhouse shall be so located with respect to the surrounding ground level that adequate drainage of the site is assured. The height of the plinth shall be not less than 450 mm from the surrounding ground level.
For Interior Courtyards and Covered Parking
Every interior courtyard shall be raised at least 150 mm above the determining ground level and shall be satisfactorily drained.
1) Habitable Rooms
- The height of all rooms for human habitation shall not be less than 2.75 m measured from the surface of the floor to the lowest point of the ceiling (bottom of slab).
- In the case of pitched roof, the average height of rooms shall not be less than 2.75 m.
- The minimum clear head room under a beam, folded plates or eaves shall be 2.4 m. In the case of air-conditioned rooms, a height of not less than 2.4 m measured from the surface of the floor to the lowest point of air-conditioning duct or the false ceiling shall be provided.
- The requirements of (given above) apply to residential, business and mercantile buildings.
- For educational and industrial buildings, the following minimum requirements apply:
- Educational: Ceiling height 3.6 m for buildings all regions; in cold regions, 3 m.
- Industrial: Ceiling height 3.6 m, buildings conditioned, 3 m (Factory Act, 1948 and rules therein shall govern such heights, where applicable)
- The area of habitable room shall not be less than 9.5 m2, where there is only one room with a minimum width of 2.4 m.
- Where there are two rooms, one of these shall not be less than 9.5 m2 and the other not less than 7.5 m2, with a minimum width of 2.1 m.
The height of a kitchen measured from the surface of the floor to the lowest point in the ceiling (bottom slab) shall not be less than 2.75 m, except for the portion to accommodate floor trap of the upper floor.
- The area of a kitchen where separate dining area is provided, shall be not less than 5.0 m2 with a minimum width of 1.8 m.
- Where there is a separate store, the area of the kitchen may be reduced to 4.5 m2.
- A kitchen, which is intended for use as a dining area also, shall have a floor area of not less than 7.5 m2 with a minimum width of 2.1 m.
iii) Other Requirements
Every room to be used as kitchen shall have,
- Unless separately provided in a pantry, means for the washing of kitchen utensils which shall lead directly or through a sink to a grated and trapped connection to the waste pipe.
- An impermeable floor.
- A flue, if found necessary; and
- A window or ventilator or opening of size not less than as specified in (below in Lighting and Ventilation of Rooms) subject to increase in area of opening in accordance with (below in Lighting and Ventilation of Rooms) (Note 3).
Lighting and Ventilation of Rooms
Rooms shall have, for the admission of light and air, one or more openings, such as windows and ventilators, opening directly to the external air or into an open Verandah.
The minimum aggregate area (see Notes 1 to 3) of such openings, excluding doors inclusive of frames, shall be not less than,
a) one-tenth of the floor area for hot-dry climate.
b) one-sixth of the floor area for warm-humid climate.
c) one-eighth of the floor area for temperate and composite climate; and
d) one-twelfth of the floor area for cold climate.
1 – If a window is partly fixed, the openable area shall be counted.
2 – No portion of a room shall be assumed to be lighted, if it is more than 7.5 m away from the opening assumed for lighting that portion.
3 – The area of openings as given in (a) to (d) above shall be increased by 25 percent in the case of a kitchen.
3) Bathrooms and Water-Closets
The height of a bathroom or water-closet measured from the surface of the floor to the lowest point in the ceiling (bottom of slab) shall not be less than 2.1 m.
- The area of a bathroom shall not be less than 1.8 m2 with a minimum width of 1.2 m. The floor area of water-closet shall be 1.1 m2 with a minimum width of 0.9 m.
- If bath and water-closet are combined, its floor area shall not be less than 2.8 m2 with a minimum width of 1.2 m.
iii) Other Requirements
Every bathroom or water-closet shall,
- be so situated that at least one of its walls shall open to external air.
- not be directly over or under any room other than another water-closet, washing place, bath or terrace, unless it has a water-tight floor.
- have the platform or seat made of water-tight non-absorbent material.
- be enclosed by walls or partitions and the surface of every such wall or partition shall be finished with a smooth impervious material to a height of not less than 1 m above the floor of such a room.
- be provided with an impervious floor covering, sloping towards the drain with a suitable grade and not towards Verandah or any other room; and
- have a window or ventilator, opening to a shaft or open space, of area not less than 0.3 m2 with side not less than 0.3 m.
No room containing water-closets shall be used for any purpose except as a lavatory and no such room shall open directly into any kitchen or cooking space by a door, window or other opening. Every room containing water-closet shall have a door completely closing the entrance to it.
4) Ledge or Tand/Loft
The minimum headroom of ledge or Tand/loft shall be 2.2 m. The maximum height of loft shall be 1.5 m.
A ledge or TAND/loft in a habitable room shall not cover more than 25 percent of the area of the floor on which it is constructed and shall not interfere with the ventilation of the room under any circumstances.
5) Mezzanine Floor
It shall have a minimum height of 2.2 m.
- The minimum size of the mezzanine floor, if it is to be used as a living room, shall not be less than 9.5 m2.
- The aggregate area of such mezzanine floor in a building shall in no case exceed one-third the plinth area of the building.
iii) Other Requirements
A mezzanine floor may be permitted over a room or a compartment, provided,
- It conforms to the standard of living rooms as regards lighting and ventilation in case the size of mezzanine floor is 9.5 m2 or more (lighting and ventilation).
- It is so constructed as not to interfere under any circumstances with the ventilation of the space over and under it.
- Such mezzanine floor is not subdivided into smaller compartments.
- Such mezzanine floor or any part of it shall not be used as a kitchen; and
- In no case shall a mezzanine floor be closed so as to make it liable to be converted into unventilated compartments.
6) Store Room
The height of a store room shall be not less than 2.2 m.
The size of a store room, where provided in a residential building, shall be not less than 3 m2.
The height of a garage shall be not less than 2.4 m.
The size of garages shall be as below:
- Private garage. 3.0 m × 6.0 m, minimum; and
- Public garage. Based on the number of vehicles parked, etc (see 10).
- The basement shall not be used for residential purposes.
- The construction of the basement shall be allowed by the Authority in accordance with the land use and other provisions specified under the Development Control Rules.
The following uses shall be permitted in the basements:
- Storage of household or other goods of ordinarily non-combustible material.
- Strong rooms, bank cellars, etc;
- Air conditioning equipment and other machines used for services and utilities of the building; and
- Parking spaces.
- The Authority may also consider permitting mercantile occupancy as well as institutional occupancy for medical, health care services involving radiation facilities in the first basement subject to compliance of all requirements for fire safety in accordance with Fire and Life Safety rules and necessary measures for required lighting, ventilation and water supply, drainage and sanitation.
- The basements can be permitted below the ground and beyond the building lines at ground level subject to a clear minimum front margin of 4.5 m and side and rear margins of 3 m, and further subject to non-habitable uses and provision for mechanical ventilation and all safety provisions and drainage (see Figure below).
- However, it is essential that the basement top slab below the external circulation at ground level should be designed for firefighting vehicular loads.
The basement shall have the following requirements:
- Every basement shall be in every part at least 2.4 m in height from the floor to the underside of the roof slab or ceiling.
- Adequate ventilation shall be provided for the basement. The ventilation requirements shall be the same as required by the particular occupancy according to Any deficiency may be met by providing adequate mechanical ventilation in the form of blowers, exhaust fans, air conditioning systems, etc.
- The height of the ceiling of any basement shall be minimum 0.9 m and the maximum, 1.2 m above the average surrounding ground level. However, in case of parking, mercantile or business occupancy at ground floor, minimum height of the ceiling of the basement may be 0.3 m above the average surrounding ground level subject to mechanical ventilation being provided (see Figure above) (mark as – a)
- Adequate arrangements shall be made such that surface drainage does not enter the basement.
- The walls and floors of the basement shall be watertight and be so designed that the effects of the surrounding soil and moisture, if any, are taken into account in design and adequate damp proofing treatment is given;
- The access to the basement shall be separate from the main and alternative staircase providing access and exit from higher floors.
- Where the staircase is continuous in the case of buildings served by more than one staircase, the same shall be of enclosed type serving as a fire separation from the basement floor and higher floors.
- Open ramps shall be permitted if they are constructed within the building line subject to the provision of (Adequate arrangements shall be made such that surface drainage does not enter the basement.).
- Access to basements through ramps shall be permitted subject to provision of (Adequate arrangements shall be made such that surface drainage does not enter the basement.).
- The requirements for the ramps shall be in accordance with ramp design.
- For all public buildings and uses including group housing, having basement going up to more than one level, access to all levels shall also be provided through lift.
- The exit requirements in basements shall comply with the provisions of Fire and Life Safety.
The chimneys shall be built at least 0.9 m above flat roofs, provided the top of the chimneys is not below the top of the adjacent parapet wall. In the case of sloping roofs, the chimney top shall not be less than 0.6 m above the ridge of the roof in which the chimney penetrates.
Parapet walls and handrails provided on the edges of roof terraces, balcony, Verandah, etc, shall not be less than 1.0 m and not more than 1.2 m in height from the finished floor level.
The size of cabins shall not be less than 3.0 m2 with a minimum width of 1.0 m. The clear passages within the divided space of any floor shall not be less than 0.75 m and the distance from the farthest space in a cabin to any exit shall not be more than 18.5 m.
In case the subdivided cabin does not derive direct lighting and ventilation from any open spaces/ mechanical means, the maximum height of the cabin shall be 2.2 m.
12) Boundary Wall
The requirements of the boundary wall are given below:
- Except with the special permission of the Authority, the maximum height of the compound wall shall be 1.5 m above the centre line of the front street. Compound wall up to 2.4 m height may be permitted if the top 0.9 m is of open type construction of a design to be approved by the Authority.
- In the case of a corner plot, the height of the boundary wall shall be restricted to 0.75 m for a length of 10 m on the front and side of the intersections and the balance height of 0.75 m, if required in accordance with (a) may be made up of open type construction (through railings) and of design to be approved by the Authority.
- However, the provisions of (1) and (2) are not applicable to boundary walls of in industrial building, electrical substations, transformer stations, institutional buildings like sanitoria, hospitals, industrial buildings like workshops, factories and educational buildings like schools, colleges, including hostels, and other uses of public utility undertakings and strategically sensitive buildings, a height up to 2.4 m may be permitted by the Authority.
- Wells, intended to supply water for human consumption or domestic purposes, where provided, shall comply with the requirements of Location and Requirements.
The well shall be located,
- not less than 15 m from any ash pit, refuse pit, earth closet or privy and shall be located on a site upwards from the earth closet or privy.
- not less than 18 m from any cess pit soak way or borehole latrine and shall be located on a site upwards from the earth closet or privy.
- such that contamination by the movement of sub-soil or other water is unlikely; and
- not under a tree or otherwise it should have a canopy over it, so that leaves and twigs may not fall into the well and rot.
- The well shall,
- have a minimum internal diameter of not less than 1 m.
- be constructed to a height not less than 1 m above the surrounding ground level, to form a parapet or kerb and to prevent surface water from flowing into a well, and shall be surrounded with a paving constructed of impervious material which shall extend for a distance of not less than 1.8 m in every direction from the parapet from the kerb forming the well head and the upper surface of such a paving shall be sloped away from the well.
- be of sound and permanent construction (Pucca) throughout. Temporary or exposed (Kutcha) wells shall be permitted only in fields or gardens for purposes of irrigation; and
- have the interior surface of the lining or walls of the well be rendered impervious for a depth of not less than 1.8 m measured from the level of the ground immediately adjoining the well- head.
14) Office-Cum-Letter Box Room
- In the case of multistoried multifamily dwelling apartments constructed by existing and proposed Cooperative Housing Societies or Apartment Owners Associations, limited companies and proposed societies, an office-cum-letter box room of dimension 3.6 m × 3 m shall be provided on the ground floor. In case the number of flats is more than 20, the maximum size of the office-cum-letter box room shall be 20 m2.
i) Business Buildings
- Provision shall be made for letter boxes on the entrance floor as per the requirements of the postal department.
15) Meter Rooms
For all buildings above 15 m in height and in special occupancies, like educational, assembly, institutional, industrial, storage, hazardous and mixed occupancies with any of the aforesaid occupancies having area more than 500 m2 on each floor, provision shall be made for an independent and ventilated meter (service) room, as per requirements of electric (service) supply undertakings on the ground floor with direct access from outside for the purpose of termination of electric supply from the licensee’s service and alternative supply cables.
The door/doors provided for the service room shall have fire resistance of not less than two hours.
- The roof of a building shall be so designed and constructed as to effectively drain water by means of sufficient rainwater pipes of adequate size, wherever required, so arranged, jointed and fixed as to ensure that the rainwater is carried away from the building without causing dampness in any part of the walls, roof or foundations of the building or an adjacent building.
- The Authority may require rainwater pipes to be connected to a drain or sewer to a covered channel formed beneath the public footpath to connect the rain-water pipe to the road gutter or in any other approved manner.
- Rain-water pipes shall be affixed to the outside of the external walls of the building or in recesses or chases cut or formed in such external walls or in such other manner as may be approved by the Authority.
- It is desirable to conserve rainwater using suitable rainwater harvesting techniques including by roof water collection.
These are some of the key building requirements that must be met in the design and construction of a building. Building codes and regulations vary by jurisdiction, so it is important to consult with local building officials to determine the specific requirements for a particular building project.