3. Stairs consists of steps arranged in a series
for purpose of giving access to different
floors of building . Since stair is often the
only means of communication between
various floors of building, location requires
good and careful consideration.
4. A stair is set of steps leading from one floor
to other . It is provided to afford the means of
ascent and descent between various floors of
building. The room or enclosure of building
in which the stair is located , is known as
staircase.
The opening or space or occupied by stairs is
known as a stairways.
5. In public buildings, stairs should be located near the
entrance . In a domestic building, stairs should be
centrally located to provide easy access to all rooms.
Stairs may be constructed by timber, bricks , stone,
steel, or reinforced cement concrete.
Stair provide access and communication between
floors in multi storey buildings , and are a path by
which fire can spread from one floor to another ,
therefore, staircase must be enclosed by fire resisting
walls , floors, ceilings and doors. It is desirable that
lining to walls and ceilings are non combustible of
low frame spread.
Stairs must be designed to carry certain loads , which
are similar to those used for design of floors
6.
7. TREAD- The upper horizontal portion of step
over which foot is placed during ascending
and descending a stairway.
RISER- The vertical of step . It is used to
support and connect successive treads.
HEADROOM- The vertical height between
tread of one flight and ceiling of overhead
construction . It should be sufficient so as not
to cause any difficulty to person using stairs.
8. NOSING- It is the projecting part of tread
beyond the face of riser. It is usually rounded
to give pleasing effect to tread and make
staircase convenient and easy to use
LINE OR NOSING- This is the straight line
touching the nosing or various steps and
parallel to slope of line.
PITCH OR SLOP- Vertical angle made by line
of nosing with horizontal .
9. LANDING- This is the horizontal platform
provided at the head of series or steps. It is used
as a resting place during use of stairs .It
facilitates change of direction of flight .
HAND RAIL- It is an inclined at convenient height
over steps .It serves as guard rail and provide
assistance to user of stairs.
BLUSTERS- It is individual vertical member made
of timber , metal or masonry fixed between
string and hand rail to give support to hand rail.
10. STRINGERS- These are the sloping members
of stair , used to support the end of steps.
WINDERS- These are the steps used for
changing the direction of stairs . These are
usually triangular in plan.
FLIGHT- This consist of series of steps
provided between landing.
RUN OR GOING- Total length of stairs in
horizontal plan including length of landings.
12. All steps lead in
one direction
This way be
continuous with
two flights with an
intermediate
landing
Adopted when
staircase is narrow
and long
Provided mostly in
porch , entrance
13. Consist of two
straight height
flights running in
opposite directions
There is no space
between the flights
in plan
Landing is provided
at level which
direction of flight
changes
14. A stair turning
through 90 degree
with the help of
level landing
Used in shops and
public buildings
15. Popularly known as
open well stairs
A well or opening is
left between forward
and backward flight
The opening is
generally used for
installation of lift
A short flight may or
may not provided in
these stairs
16. These stairs may have
any geometrical shape
and they require no
newel post
This type of stairs is
similar to open newel
stair except the well
formed between
forward and backward
flight is curved
Change of direction in
such stairs is achieved
by winders and not by
landings.
17. All the steps are
radiate from a
newel post or well
hole
All the steps are
winders
This is provided
where space is
limited and traffic is
casual
Mostly located at
rear of building
18.
19. These are light in
weight and easy to
construct but they
have very poor fire
resistance , They
are used only for
small rise
residential
buildings.
Sometimes, fire
resisting hard wood
of proper thickness
20. These stairs are widely
used at places where
ashlars stone is
readily available .
Stone stairs are quite
strong and rigid ,
through they are very
heavy. Stone used for
construction of stairs
should be hard , strong
and resistant to wear.
The simplest form of
stone stairs is those
supported on both the
ends , through an open
well staircase can also
be built.
21. These are not very
common , except
the entrance .
However , brick
stairs of single
straight flight are
often made in
village houses. The
stairs consist of
either solid wall ,or
also, arched
openings may be
left for obtaining
storage space.
22. Stairs of mild steel
or cast iron are
used only as
emergency stairs.
They are not
common in
residential and
public buildings,
though these are
strong and fire
resistance. These
are commonly used
in factories,
godowns,
23. These are widely
used for residential
, public and
industrial buildings.
They are strong,
hard wearing and
fire resisting. These
are usually cast –
in- situ and a wide
variety of finishes
can be used on
these.
24. LANDING – The width of landing should not be less
than the width of stairs
WIDTH OF STAIRS - Residential – 0.8 to 1m
Public- 1.8 to 2m
TREAD- Residential- 220- 250mm
Public – 250-300mm
not less than 200mm in any case
RISER - Residential – 150- 180mm
Public – 120-150mm
not more than 200mm in any case
PITCH – Should not be more than 38 degree
