Chapter-7 General Building Requirements/ General Building Requirements/Provisions, Section 7.11 Staircase Details

  1. Interior stairs shall be constructed of non-combustible material. They will be constructed as a self-contained unit and be mechanically ventilated if completely enclosed in low rise residential buildings.
  2. A staircase shall not be arranged round a lift shaft.
  3. Hollow combustible construction shall not be permitted.
  4. The minimum width of an internal staircase is given in bye-law No. 7.11.2. f.
  5. The minimum width of treads without nosing shall be 25 cm for an internal staircase for low rise residential buildings. In the case of high rise residential buildings, the minimum tread shall be 30 cm. The treads shall be constructed and maintained in a manner to prevent slipping.
  6. Winders shall be allowed in low rise residential buildings provided they are not at the head of a downward flight.
  7. The maximum height of riser shall be 19 cm in the case of low rise residential buildings and 15 cm in the case of high rise residential buildings. The maximum number of risers per flight shall be limited to 15 per flight.
  8. Handrails shall be provided with a minimum height of 1.0 m from the centre of the tread subject to the condition that balusters/railings do not reduce the width of the staircase.
  9. The minimum headroom in a passage under the landing of a staircase and under the staircase shall be 2.2 m.
  10. For buildings 15 m in height or more, access to the main staircase shall be through a fire check door having a minimum two hours fire resistance rating, which may be reduced to one hour for residential buildings (except hotel/ starred hotels).
  11. No living space, store or other fire risk shall open directly into the common staircase or staircases, in case of group housing.
  12. External exit doors of the staircase enclosure at the ground level shall open directly to the open spaces or can be reached without passing through any door other than a door provided to form a draught lobby.
  13. The main staircase and fire escape staircase shall be continuous from ground floor to the terrace level. n. No electrical shafts/ AC ducts or gas pipe etc. shall pass through the staircase. However, ducting in the staircase may be permitted if it is of 1 hour fire resistance rating.
  14. The lift shall not open in the staircase landing. Adequate Lift Lobby shall be provided, except in low rise residential plotted development upto 500 sqm.
  15. No combustible material shall be used for decoration/wall panelling in the staircase.
  16. Beams/columns and other building features shall not reduce the head room/width of the staircase.
  17. The exit sign with an arrow indicating the way to the escape route shall be provided at a suitable height from the floor level on the wall and shall be illuminated by electric light or glow sign or florescent, connected to corridor circuits. All exit way marking signs should be flush with the wall and so designed that no mechanical damage shall occur to them due to moving of furniture or other heavy equipment. Further all landings of floor shall have floor-indicating boards indicating the number of floor as per these bye-laws. The floor indication board shall be placed on the wall immediately facing the flight of stairs and nearest to the landing. It shall be of size not less than 0.5 m x 0.5 m.
  18. Individual floors shall be prominently indicated on the wall facing the staircase.
  19. In the case of single staircases, they shall terminate at the ground floor level and the access to the basement shall be by a separate staircase. However, the second staircase may lead to basement levels provided the same is separated at ground level either by ventilated lobby with discharge points at two different ends through enclosures.
  20. The use of spiral staircase shall be limited to low occupant load and to a building of height 9 m. A spiral fire escape shall be not less than 1.5 m in diameter and shall be designed to give adequate head room.

Minimum Width Provision for stairways in residential buildings shall be 1.35 m.

Minimum Width Provisions for Passageway/Corridors in residential buildings shall be-

  1. 1 .m. for single loaded and 1.5 m for double loaded low rise, dwelling unit type residential buildings.
  2. 1.35m for single loaded and 1.8m for double loaded in residential buildings such as hostels and group housing.