staircase presentation ppt

1. STAIR CASE
GROUP
Abdalla Mowlid
Usama Abdi Nasir

2. CONTENTS
• ✓INTRODUCTION
• ✓COMPONENTS OF STAIRCASES
• ✓TYPES OF STAIRCASES
• ✓STRUCTURAL BEHAVIOUR OF STAIRCASES
• ✓POINTS OF CONSIDERATIONS
• ✓BAD STAIR

3. Introduction
• STAIRS CONSIST OF STEPS ARRANGED IN A SERIES FOR THE PURPOSE
OF GIVING ACCESS TO DIFFERENT FLOORS OF BUILDING.SINCE STAIR
IS OFTEN THE ONLY MEANS OF COMMUNICATION BETWEEN THE
VARIOUS FLOORS OF BUILDING,THE LOCATION REQUIRES GOOD AND
CAREFUL CONSIDERATION.
• What is stair?
• A Stair is a system of steps by which people and objects may pass
from one level of a building to another.”

4. COMPONENTS OF STAIRCASES
• TREAD:-THE UPPER HORIZONTAL PORTION OF STEP OVER WHICH
FOOT IS PLACED DURING ASCENDING AND DESCENDING A
STAIRWAY.RISER:-
• THE VERTICAL MEMBER OF STEP.IT IS USED TO SUPPORT AND
CONNECT SUCCESSIVE TREADS.HEADROOM:-THE VERTICAL HEIGHT
BETWEEN THE TREAD OF ONE FLIGHT AND CEILING OF OVERHEAD
CONSTRUCTION.
• IT SHOULD BE SUFFICIENT SO AS NOT TO CAUSE ANY DIFFICULTY TO
PERSON USING THE STAIRS.

5. • STRINGERS:-THESE ARE THE SLOPING MEMBERS OF THE STAIR, USED
TO SUPPORT THE END OF STEPSWINDERS
• :-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 LANDINGSRUN OR
GOING:-TOTAL LENGTH OF STAIRS IN HORIZONTAL PLAIN INCLUDING
LENGTH OF LANDINGS

6. TYPES OF STAIRCASES
• A) STRAIGHT STAIRS
• B) DOG-LEGGED
• C) CIRCULAR STAIRS
• STRAIGHT STAIRS Straight stairs are stairs without any changes in
direction. They are certainly one of the most common types of stairs
found in both residential and commercial properties. Below are
examples of straight floating stairs made with a variety of stringer
styles, railing types, and wood species.

7. • B) A dog-leg is a configuration of stairs between two floors of a
building, often a domestic building, in which a flight of stairs ascends
to a half-landing before turning at a right angle and continuing
upwards. The flights do not have to be equal, and frequently are not.

8. • C) CIRCULAR STAIRS are helical staircases that lead upstairs in a
flowing arc. Unlike Spiral Staircases, the Circular Staircase does not
require a fixed central column, and it usually has two rolled stringers
with treads attached between them. Circular Stairs are helical
staircases that lead upstairs in a flowing arc

9. STRUCTURAL BEHAVIOUR OF STAIRCASES
• A) Where supported at top and bottom risers by beams spanning
parallel with the risers, the distance c/c of beams.STRUCTURAL
BEHAVIOUR OF STAIRCASE.
• B) b) Where spanning on to the edge of a landing slab, which spans
parallel, with the risers, a distance equal to the going of stairs plus at
each end either half the width of the landing or one metre, whichever
is less.
• C) Where the landing slab spans in the same direction as the stairs,
they shall be considered as acting together to form a single slab and
the span determined as distance c/c of supporting beams or walls,
the going being measured horizontally.

10. POINTS OF CONSIDERATIONS
• LANDING WIDTH : Should not be less than the width of stairs.
WIDTH OF STAIRS : Residential – 0.8m to 1m Public – 1.8m to 2m
TREAD : Residential – 220mm to 250mm Public – 250mm to 300mm
RISER : Residential – 150mm to 180mm Public – 120mm to 150mm
PITCH : Should be not more than 38 HEAD ROOM CLEARENCE
LENGTH OF FLIGHT: Number of steps should be min. 3 and max. 12
DESIGN OF STAIRCASE 14 Not less than 200mm in any case Not less
than 200mm in any case Should not be less than 2.1m

11. BAD STAIR