REQUIREMENTS OF GOOD STAIRCASE

  

A well designed stair should provide an easy Quick and safe access b/w the floors.

Ø Design of Layout

a)     Ht. of floor known.

b)    The position of 1^st & last riser are determined according to the positions of doors, windows and verandahs.

c)     The ht. of the riser is assumed as per requirement.

d)    Number of risers = Total ht. of floor/ height of riser.

e)     No. of treads in a flight = no. of risers -1

Ø Treads and Risers:

          They should be suitably proportioned & the following thumb rule can be

           used.

                                                                   i.            (Rise + going) = 40 to 45 cm.

                                                                 ii.            (Rise x going) = 410 to 450 cm approx.

                                                              iii.             (2 x Rise + going) = 60 cm approx.

                                                              iv.            Take Rise=140mm & going = 300mm as standards.

Residential building – Rise not more than 230mm

                                       Going not less than 230mm

Public building – Rise not more than 180mm

                               Going not less than 270mm

Ø The Going & rise should be constant throughout the stair or at least throughout the flight.

Ø Inclined Risers can be provided when the space is not adequate for treads, inclined risers can be provided.

Ø Materials and Workmanship:

§  It should be of Sound materials

§  Good workmanship so as to import strength & durability.

§  Stairway provides fire path from floor to floor and i.e. it should be of fire proof mat (Non-combustible & low flame spread).

Ø Width :

§  Width should be sufficient for two persons to pass on it simultaneously.

§   The min. width of stair = 800mm.

§  If width exceeds 1.80m it is desirable to provide central handrail.

Ø Pitch:

§  The inclination of a stair to the horizontal should be limited to 30^oto 45^o .

Ø Headroom:

§  It should be preferably not less than 2m.

Ø Flight:

§  It is not desirable to provide a flight with less than 3steps  & more than 12 or almost 15 steps.

Ø Winders

§  These  are to be avoided as for as possible.

§  If unavoidable it should be provided at the bottom of the flight.

Ø Hand Rails:

o   Handrails has to be provided at least on one side when the flight consists of more than 3steps.

o   It should be provided on 2 sides for wide stairs.

o   For very wide stairs- a central handrails should be provided.

o   The height of handrails above the riser should be approx. 800mm.

Ø Location:

Stairs should be located that they are

ü Well- lighted

ü  well –ventilated

ü  have convenient and spacious approaches.

ü In Public building- stair located near the main entrance.

ü In Residential building- stair located in the central portion so as to have easy access from all rooms.