STRUCTURAL SAFETY



Chapter 5    

STRUCTURAL SAFETY AND BUILDING SERVICES

5.0 The structural design of foundation, masonry, timber, plain concrete, reinforced concrete, prestressed concrete and structural steel shall be carried out in accordance with Part-VI structural design, section-1 loads, section-2 foundation, section-3 wood, section-4 masonry, section-5 concrete and section-6 steel of National Building Code of India taking into consideration all relevant Indian Standards prescribed by Bureau of Indian Standards including the Indian Standard given in IS-Code 1893-1984, 13920-1993, 4326-1993, 13828- 1993, 13827-1993 and 13935-1993 for structural safety. 
 
5.1 Occupant load: The population in rooms, area of floors shall be calculated based on the occupant load given in the table below:-   

S.No. Group of Occupancy Occupant Load Gross area* in m2/person 
1 Residential  12.5
2   4
3 Institutional  15+
4 Assembly a. With fixed or loose seats and dance floors b. Without seating facilities including dining rooms 

0.6+

1.5+

5 Mercantile a. Street floor and sales basement b. Upper sale floors 

3

6

6 Business and industrial  10
7 Storage  30
8 Hazardous  10


 * The gross area shall mean plinth area or covered area. +    Occupant load in dormitory portions of homes for the aged, orphanages, insane asylums, etc. where sleeping accommodation is provided, shall be calculated at not less than 7.5 m2 gross area person. ++ The gross area shall include, in addition to the main assembly room or space, any occupied connection open or space in the same storey or in the storeys above or below, where entrance is common to such rooms and spaces and they are available for use by the occupants of the assembly place. No deductions shall be made in the gross area for corridors, closets or other sub- division; one area shall include all space serving the particular assembly occupancy. 
 
5.2. Quality of materials and workmanship: All material and workmanship shall be of good quality conforming generally to accepted standards of Public Works Department and Indian Standard Specification and Codes as included in Part-V Building Materials and Part-VII Construction Practices and Safety of National Building Code of India. 
 
 5.2.1. Alternative materials, methods of design and construction and tests: The provision of the ByeLaws are not intended to prevent the use of any material or method of design or construction not specifically prescribed by the bye-law provided any such alternative has been approved. The building materials approved by B.I.S. or any statutory body will form part of the approved building material and technology as part of the Bye-Laws. 5.3. Building services 5.3.1. The Planning design and installation of electrical installations, air conditioning installation of lifts and escalators can be carried out in accordance with Part-VIII Building Services, Section–2 Electrical Installation, Section–3 Air conditioning and heating, Section-5 installation of Lifts and 

 
Delhi Urban Art Commission                                                                                              
 
Escalators of National Building Code of India. However deviations from National Building Code may be done as per good Engineering Practices. 5.3.2. The number and type of lifts to be provided in different buildings sha1l be as given in Annexure 5. 5.3.3. The requirements of electric sub-station are given in Annexure-6. The provision of electric substation shall also require approval from Electricity Board concerned. 
 
5.4.    Plumbing services

5.4.1. The planning, design, construction and installation of water supply, drainage and sanitation and gas supply system shall be in accordance with Part-IX Plumbing Services, section-l water supply; Section-2 Drainage and Sanitation and Section-3 Gas Supply of National Building Code of India.

5.4.2 Requirement of water supply for various occupancies in buildings shall be as given in Table

5.1, 5.2, and

5.3. 5.4.3 Requirement of sanitary fittings and installations for different occupancies in buildings shall be as given in Table

5.4 to 5.15. for calculation of occupancy.Table

5.1 Per capita water requirement for various Occupancies/Uses 
 

S.No Type of occupancy Consumption (in lt.
1 Residential ii. In dwelling units( per head per day) iii. Hotels with lodging accommodation (per bed

135

180 

2 Educational  a) Day schools( per head per day) b) Boarding schools( per head per day

135

180 

3 Institutional(medical hospitals) a)no. of beds not exceeding 100 b)no. of beds exceeding 100 c) medical quarters and hotels 

340

450

135

4 Assembly – cinema theatres, auditoria, etc.  (per seat accommodation)  15
5 Government or semi public business  45
6 Mercantile(commercial) a) Restaurants(per seat) b) Other business building   
7 Industrial a) Factories where bath- rooms are to be provided. b) Factories where bath-rooms are not to be provided 

 

45

30 

8 Storage(including warehouses 30 
9 Hazardous 30 
10 Intermediate stations (excluding mail and express stops 45(25)* 
11 Junction stations 70(45)*
12 Terminal stations  45 
13 International and domestic Airports 70 

 

* The values in parenthesis are for such stations, where bathing facilities are not provided. Note: The number of persons for Sl. No. 10 to 13 shall be determined by the average number of passenger handled by the station daily with due consideration given to the staff and workers likely to use the facilities. 
 

S.No Classification of building Storage capacity 
1 For tenements having common convenience 900lt. per W.C. seat 
2 For residential premises other than tenement having common conveniences.  common conveniences. 
270lt. net for one W.C. seat each and 180lt. for each additional seat in the same flat. 3
3 For factories and workshops  900lt. per W.C. seat and 180 lt. per urinal
4 For cinemas, public assembly hall, etc. 900lt. per W.C. seat and 350 lt. per urinal

 

S.No No. of floors Storage capacity Remarks 
For premise occupied tenements with common conveniences
1 Ground floor Nil Provide down take fittings are installed 
2 Floors 2, 3, 4, 5 and upper floors  500  litres per tenement  
For premises occupied as flats or blocks 
3 Ground floor Nil  
4 Floors 2, 3, 4, 5 and upper floors  500  litres per tenement Provide down take fittings are installed 

Note

1: If the premises are situated at a place higher than the road level in front of the premises, storage at ground level shall be provided on the same lines as on floors.

2: The above storage may be permitted to be installed provided that the total domestic storage calculated on the above basis is not less than the storage calculated on the number of down take fittings according to scale given below

 i. Down take taps              70 l. each

ii. Showers                       135 l. each

iii. Bathtubs                      200 l. eac

Table 5.4 Sanitation requirements for Shops and Commercial Offices 

S.No Sanitary Unit/Fittings  For Personnel 
1 Water closet One for every 25 persons or part thereof exceeding 15(including employees and customers).For female personel 1 for every 15 persons or part thereof exceeding 10. 2
2 Drinking water fountain  One for every 100 person with a minimum on one on each floor
3 Wash basin One for every 25 persons or part thereof
4 Urinals Same as S.No. 3 of table 5.9 
5 Cleaners’ sink One per floor minimum, preferably in or adjacent to sanitary rooms

Note: Number of customers for the purpose of the above calculation shall be the average number of persons in the premises for a time interval of one hour during the peak period. For male-female calculation a ratio of 1: 1 may be assumed.Note:    

 i) It may be assumed that the two-thirds of the number are males and one- third female

 ii) One water tap with drainage arrangements shall be provided for every 50 persons or part thereof in the vicinity of water closet and urinals. Nursery SchoolsNote:

1. one water tap with draining arrangements shall be provided for every 50 persons or part thereof, in the vicinity of water closets and urinal.

2. For teaching staff, the schedule of sanitary units to be provided shall be the same as in case of office buildings 

Note:-

One water tap with drainage arrangements shall be provided for every 50 persons or part thereof in the vicinity of water closet and urinals. 

Note:-

Where only one water closet is provided in a dwelling , the bath and water closet shall be separately accommodated.  

Table 5.11 Sanitation Requirements for Assembly Occupancy Buildings (Cinema, Theaters, Auditoria, etc.) Note:-

It may be assumed that two thirds of the number are males and one third female.    Note:-

 It may be assumed that two thirds of the number are males and one third female.   

Note:-

It may be assumed that two thirds of the number are males and one third female.  

Note:-

1    For many trades of a dirty or dangerous character, more extensive provisions  are required.   

Note :  Provision for wash basins, baths including shower stalls, shall be in accordance with part ix section 2- Drainage and Sanitation of National Building Code of India and amendments time to time.

 * At least one Indian style water closet shall be provided in each toilet.  Assume 60 % males and 40 % females in any area. 

5.5 Notes – Water Supply arrangements (General Guidelines)  

5.5.1 For new construction: Provision shall be made for underground tank for the storage of water, having capacity at 200 lts. per person with adequate pumping arrangements to supply water to upper floors. Filtered water connection will be allowed only for use of drinking and bathing needs. For other purposes i.e. flushing and gardening etc., the individual shall be required to have own arrangements of tube well water within the premises. While according sanction to Layout Plan, the Authority shall make a special mention that provision for space shall be kept for the construction of underground reservoir of adequate capacity along with booster pumping station.

5.5.2 Arrangements as given in 5.5.1 above shall also be provided in Group Housing Societies.

5.5.3 The plumbing arrangement in case of new constructions shall be made in a way that the potable water shall be used for drinking, cooking & bathing only and for rest of the uses, provision for ground water can be made with dual piping system

 5.5.4  Low capacity cistern should preferably be provided instead of normal 12.5 l. capacity

5.6 Water Harvesting:

Water harvesting through storing of water runoff including rainwater in all new buildings and reconstructed buildings on plots of 100 sq m. and above will be mandatory.

5.6.1 The plans submitted to the local bodies shall indicate the system of storm water drainage along with points of collection of rain water in surface reservoirs or in recharge wells.

5.6.2 All building having a minimum discharge of 10,000 l. and above per day shall incorporate waste water recycling system. The recycled water should be used for horticultural purposes. 

5.7 Installation of Solar Assisted Water Heating System in Buildings:      

 5.7.1 Definitions 5.7.2  Installation of Solar Water Heating Syste

5.7.2.1 New Buildings: Clearance of plan for the construction of new buildings of the aforesaid categories shall only be given if they have a provision in the building design itself for an insulated pipeline from the rooftop in the building to various distribution points where hot water is required. The building must have a provision for continuous water supply to the solar water heating system. The building should also have open space on the rooftop, which receives direct sun light. The load bearing capacity of the roof should at least be 50 kg. per sq m. All new buildings of above said categories must complete installation of solar water heating systems before obtaining necessary license to commence their busines

5.7.2.2 Existing Buildings: Installation of Solar Assisted Water Heating Systems in the  existing building shall be made mandatory at the time of change of use to above said category provided there is a system or installation for supplying hot water.

5.7.2.3  Capacity: The capacity of solar water heating system to be installed on the building of different categories shall be decided in consultation with the local bodies. The recommended minimum capacity shall not be less than 25 litres per day for each bathroom and kitchen subject to the condition that maximum of 50% of the total roof area is provided with the system.

5.7.2.4 Specifications: Installation of Solar Assisted Water Heating Systems shall conform to BIS specification IS 12933. The solar collectors used in the system shall have the BIS certification mark.  

5.7.3   Auxiliary System: Wherever hot water requirement is continuous, auxiliary heating arrangement   either with electric elements or oil of adequate capacity can be provided.  

5.7.4 No new building in the following categories in which there is a system of installation for supplying hot water shall be built unless the system of the installation is also having an auxiliary solar assisted

water heating system:-

5.7.4.1 Hospitals and Nursing Home.

5.7.4.2  Hotels, Lodges, and Guest Houses, Group Housing with the plot area of 4000 sq m.

5.7.4.3 Hostels of Schools, Colleges and Training Centres with more than 100 Students.

5.7.4.4 Barracks of armed forces, paramilitary forces and police.

5.7.4.5 Individual residential buildings having more than 150 sq m. plinth area.

5.7.4.6 Functional Buildings of Railway Stations and Air Ports like waiting rooms, retiring rooms, rest rooms, inspection bungalows and catering units.

5.7.4.7 Community Centres, Banquet Halls, Barat Ghars, Mangal Karyalayas and buildings for similar use 

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