Table of Contents
1. Staircase Calculator
Before executing the calculator, read all standard sizes of Tread and Rise given below:
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2. Staircase Design Formulas
Before entering the design of the staircase, there are several criteria or you can formulas that should be known.
a. Relation Between Riser and Tread
| T+2R= 600 mm |
b. Standard Values:
The design of the staircase should build it within the limit of government policies. So, always be aware while assuming the value of tread and riser.
a. For Residential Building: T = (220 – 270) mm, R= (150 – 170) mm
b. For Public Building: T = (250-300) mm, R= (100-150) mm
| Country | Tread (mm ) | Rise (mm) |
| India | ||
| Residential Building | 200-250 | 190 to 200 |
| Commercial Building | 300 | 150 to170 |
| United States | ||
| 279 (Minimum) | 240 (Minimum) | |
| Philippines | ||
| 750 | 200 | |
| Malaysia | ||
| 260-370 | 140-190 | |
| Nepal | ||
| Residential Building | 220 – 270 | 150 – 170 |
| Public Building | T= 250-300 | R= 100-150 |
c. Usual Sizes of steps
a. For Residential Buildings: (150 x 270) mm to (170 x 220)mm
b. For Public Building: (100 x 300) mm to (150 x 250) mm
d. Types of Staircases:
a. Public Building = Open well staircase
b. Residential Building = Dog-legged Staircase
| Total Length of stair = NTxT+L+E |
Where,
NT= Number of Tread
T = Size of Tread
L= Landing
E= Entry Space
| Number of treads (NT) = NR-1 |
Where,
NR = Number of Riser
3. Numericals of Staircase Design
1. Draw a plan of a dog-legged staircase for a building in which the vertical distance between floors is 3.6 m. The stair hall measures 2.5 m x 5m.
Given,
Floor Height = 3600 mm
Types of staircase = Dog Legged staircase
Assume,
Riser (R)= 150 mm
Number of risers (NR) = 3600 / 150 = 24 nos
Number of Riser in One Flight = 24/2 = 12 nos
Number of Tread in one Flight = 12-1 = 11 nos
Now,
T+2R = 600
T + 2×150= 600
T= 600-300
T= 300 mm
Size of tread = 300 mm
Width of stair = 1200 mm
Size of Landing = Width of stair = 1200 mm
Entry Space(E) = 5000-1200-11×300 = 500 mm
Here, is our design of staircase.
2. Design a proper layout of an RCC Stair for a hospital that consists of the ground floor and first floor from the following data.
Inside Dimensions of staircase = 6m x 4.5 m
Height of each floor = 3.75 m
The thickness of the floor slab= 150 mm
Height of stair cabin = 2.50 m
Width of stair= 1.5 m
Solution,
Total Floor Height = 3750+150 = 3900 mm
Types of Staircase = Open well Staircase
Assume,
Riser (R) = 150 mm
Total Number of riser = 3900/150 = 26 nos
Now,
T+2R= 600
T= 600- 2×150
T= 300 mm
Also, the width of the stair = 1500 mm
Landing of stair = 1500 mm
Here provide 9 treads in the First Flight, 5 treads in the second flight, and 9 treads in the third flight.
Entry Space (E) = 6000-1500-9×300 =1800 mm
Here, is our design of the staircase.
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