1. Ricardo Brown St. Mary High School
STAIRCASES
Ricardo Brown
St. Mary High School

2. Objectives. Students will be able to:
Explain what is a staircase
State three function of stairs
Distinguish clearly between at least eight (8) different types of stairs
On a diagram identify at least ten (10) different parts on a stair

3. STAIRS
Stairs are the medium through which a person can travel from one horizontal level to another horizontal level although it connects two different horizontal levels.

4. STAIRCASE: A stair is a set of steps leading from one floor to the other. It is provided to afford the means of ascent and descent between various floors of the building. The room or enclosure of the building, in which the stair is located, is known as staircase. The opening or space occupied by the stair is known as a stairway. In a domestic building the stairs should be centrally located to provide easy access to all rooms. In public buildings, stairs should be located near the entrance. Stairs may be constructed by timber, bricks, stone, steel or reinforced cement concrete.

5. Staircases provide access and communication between floors in multi-storey buildings, and are a path by which fire can spread from one floor to another.
Staircase, therefore, must be enclosed by fire resisting walls, floors, ceiling and doors. It is desirable that the linings to the walls and the ceilings are non- combustible and of low flame spread.
Another important aspect in the design of stairs is the strength aspect. It must be designed to carry certain loads, which are similar to those used for the design of floor.

6. STAIRS TYPES Single flight straight stairs
Double flight straight stairs
Quarter turn newel
Half turn newel
Open well stairs
Dog legged stairs
Bifurcated stairs
Circular stairs
Spiral stairs
Geometrical stairs

7. DOUBLE FLIGHT STRAIGHT STAIRS
Here the stairs posses two landings while running straight in the complete flight.
QUARTER TURN NEWEL
In quarter turn newel the stairs run straight in a flight and after reaching the landing the stairs it turns to either left or right at ninety degree and its runs again till it reaches the consecutive horizontal level.

8. Types of Stairs
Quarter Turn

9. Stair Types

10. Quarter Turn Stair B C D E A F G H K I J L N M

11. Quarter Turn Stair

12. HALF TURN NEWEL
In half turn newel stairs the stairs runs straight and after reaching the landing it turns to left or right and then climbs up to next two to three steps and reaches a landing and these steps again turns in the direction from where the user was approaching reaching finally to the consecutive horizontal level.
OPEN WELL STAIRS
These are like normal doglegged stairs but the only difference is that after reaching the landing the stairs ends up with a railing instead of the wall.

13. DOG LEGGED STAIRS
Dog legged stairs are the stairs in which the user climbs up to a flight turns at one eighty degree and then climb stairs in opposite direction
BIFURCATED STAIRS
In bifurcated stairs the stairs runs at a flight an as it reaches the landing the stairs runs from left and right side reaching the same horizontal level these stairs are provided generally in atrium of a building.

16. CIRCULAR STAIRS
The stairs made in in a circular form are known as the circular staircase.

17. SPIRAL STAIRS Those stairs which are in spiral form is known as spiral staircase.

18. GEOMETRIC STAIRS
Geometric

19. PARTS OF A STAIR CASE

20. Technical terms associated with the design and constructions of stairs TREAD: it is the upper horizontal portion of a step upon which the foot is placed while ascending or descending. RISER: it is the vertical portion of a step providing a support to the tread. FLIGHT: this is defined as an unbroken series of steps between landings. LANDING: it is the level platform at the top or bottom of a flight between the floors. A landing facilitates change of direction and provides an opportunity for taking rest during the use of the stair.

21. RISE: it is the vertical distance between two successive tread faces
RISE: it is the vertical distance between two successive tread faces. GOING: it is the horizontal distance between two successive riser faces. STRINGS AND STRINGERS: these are the slopping members which support the steps in a stair. They run along the slope of the stair. NEWEL POST: newel post is a vertical member which is placed at the ends of flights to connect the ends of strings and hand rail.

22. BALUSTER: it is vertical member of wood, metal or other material supporting the hand rail.
HAND RAIL: it is the surrounded or moulded member of wood or metal following generally the contour of the nosing line, and fixed on the top of balusters.

23. 2 Flights
1 Flight
Definition – Flights Between Landings
Dogleg Closed Riser
Straight Open Riser

24. Half Space Landing Change stair direction 180⁰
Landing width = width of stair (min 750mm)
Used in Dogleg Stairs

25. Quarter Space Landing Change Stair Direction 90⁰
Landing Width & Length = Stair Width
Forms Quarter Turn Stair (min 750mm)

26. Intermediate Landing Allows the Stair to continue in same direction
Required where more than 18 Risers
May be used to give a rest
Width = Stair Width
Length = Stair Width or greater

27. Quarter Space Landing

28. Parts of Stairs

29. Parts of Stairs

30. Parts of Stairs

31. Parts of Stairs

32. Parts of Stairs

33. Parts of Stairs

34. Parts of Stairs

35. Parts of Stairs

36. Parts of Stairs

37. Parts of Stairs

38. Parts of Stairs

39. Class exercise
Make a neat sketch of a timber staircase and label the following parts: tread, riser, newel, spandrel, handrail, baluster, string, landing, flight, wedge, glue block
Explain the following terms: staircase, spandrel, landing, string, tread, riser.
State three functions of a stair

40. Objectives. Students will be able to:
List at least four materials from which stairs are made
Use sketches to illustrate how timber stairs are fitted
Determine the size of risers by calculation
Determine the size of treads by calculation
Determine the going of a stair by calculations.

41. STAIRS OF DIFFERENT MATERIALS
TIMBER STAIRS: these stairs 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 may be used.
STONE STAIRS: these are widely used at places where ashlar stone is readily available. Stone stairs are quite strong and rigid, though 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, though an open well stair case can also be built.

42. STAIRS OF DIFFERENT MATERIALS
BRICK STAIRS: these are not very common, except at 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.

43. METAL STAIRS: stairs of mild steel or cast iron are used only as emergency stairs. They are not common in residential and public buildings, though they are strong and fire resistant. These are commonly used in factories, godowns, workshops, etc.
R.C.C: these are the stairs 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.

44. Timber Stairs

45. Metal Stairs

46. Concrete Stairs

47. Stone Stairs

48. Glass Stair

49. Combination of Materials

50. Winders Treads that are tapered Must have same rise as the flights
Maximum of 3 treads per quarter turn
Must be same width at centre on widths < 1m
If stair > 1m same width 400mm from inside handrail

51. Winders

52. MODELS OF STAIRS

54. Stair Types

55. Stair Types
Double Closed Stair

56. Stair Types

57. Stair Types

58. Double Open Sided Stairs

59. In this case one side is closed while the other is open

60. The Bracketed Stairs refers to decoration & Cut String
Also Known as Cut String

61. Spine String Stair

64. GEOMETRICAL STAIRS

69. Definitions

70. Rise & Going must stay the same within flight

72. CHECK YOUR LEARNING

74. Stair Requirements

75. Stair Requirements

76. Calculate Stair No Restriction on Going
Determine Total Rise
= 2700
Best Going
2R + G Between 550 to 700
Midpoint = 625
Say 175mm
Select suitable Rise
= 2700/175 =
Divide Total Rise by Rise
Either 15 or 16 Risers = 2700/15 = 180mm
2700/16 = mm
Use 180mm is closer to 175mm

77. Determine Best Going BCA states that going must be within the range
2 x Rise (R) + Going(G) = 550 to 700
We can assume that the best answer is the Midpoint ( )/2 = 625
Best Going 2R + G = 625
Best Going G = 625 – 2R

78. Calculate Stair No Restriction on Going
Best Going
2R + G Between 550 to 700
Midpoint = 625
Determine Total Rise
= 2700
Say 175mm
Select suitable Rise
= 2700/175 =
Divide Total Rise by Rise
Either 15 or 16 Risers = 2700/15 = 180mm (Use)
2700/16 = mm
Determine Best Going 2R + G = 625
G = 625 – 2R
Best Going for180 Riser 265 = 625 – 2 x 180
Either
Rise 180
Going 265

79. Calculate Stair No Restriction on Going
Use
Rise 180
Going 265
15 Risers
14 Goings

80. Calculate Stair Restriction on Going
Best Going
2R + G Between 550 to 700
Midpoint = 625
Preferred Rise 175mm
Divide Total Rise by Rise = 2700/175 =
Either 15 or 16 Risers = 2700/15 = 180mm
2700/16 =
Use 180mm
Determine Best Going
3800/14 = x 180 = (Closest)
3800/15 = x = 591
15 Risers
14 Goings
Use
Rise 180
Going

81. Calculate Stair Flight with Quarter Turn
Stair width 900mm
Once an Intermediate Landing is introduced the top flight becomes constrained

82. Calculate Stair Flight with Quarter Turn
Best Going
2R + G Between 550 to 700
Midpoint = 625
G = 625 – 2R
Stair width 900mm
Preferred Rise = 165mm
2700/165 =
/16= (3.75 Diff)
2700/17= (6.176 Diff)
Use Rise =
Best Going = 625 – 2R
= 625 – 2 x
= 287.5
1800/287.5 = 6.261
/6 = (12.5 Diff)
1800/7 = ( Diff)
Rise =
Going = 300

83. Calculate Stair Flight with Quarter Turn
Best Going
2R + G Between 550 to 700
Midpoint = 625
G = 625 – 2R
Stair width 900mm
Preferred Rise = 165mm
2700/165 =
/16= (3.75 Diff)
2700/17= (6.176 Diff)
Use Rise =
Best Going = 625 – 2R
= 625 – 2 x
= 287.5
1800/287.5 = 6.261
/6 = (12.5 Diff)
1800/7 = ( Diff)
Rise =
Going = 300

84. Calculate Stair Constrained Flight with Quarter Turn
Best Going
2R + G Between 550 to 700
Midpoint = 625
x 180 = 265
Stair width 900mm
From Previous we know
15 Risers at 180
Length of 1st Flight =
Divide by Best Going = 1800/265
= 6.79
Going Either 1800 /6 = 300mm
1800/7 = 257mm
is Closest to 265

85. Calculate Stair Constrained Flight with Half Space Landing
Preferred Riser 170mm
3600/170 =
/21 =
3600/22 =
Use mm
Best Going = 625 – 2R
= 625 – 2 x =
Length of 1st Flight = 4050 – 900
= 3150
Divide by Best Going = 3150/
= 11.16
/11 =
- 3150/12 =
Use
Stair width 900mm

86. Calculate Stair Constrained Flight with Half Space Landing
Preferred Riser 170mm
Rise mm
Going
Stair width 900mm

87. Calculate Stair Constrained Flight with Quarter Turn Winders
Preferred Riser 170mm
4100/170 =
/24 =
/24 = 164
Use Rise
Best Going
625 – 2R = BG
625 – 2 x =
2650/ = 9.353
2650/9 = (USE)
2650/10 = 265
Rise
Going
Stair width 900mm

88. Calculate Stair Constrained Flight with Quarter Turn Winders
Preferred Riser 170mm
4100/170 =
/24 =
/24 = 164
Use Rise
Best Going
625 – 2R = BG
625 – 2 x =
2650/ = 9.353
2650/9 = (USE)
2650/10 = 265
Rise
Going
Stair width 900mm

89. Calculate Stair Constrained Flight with Half Space Landing
Stair width 950mm
Preferred Riser 170mm
3400/170 = 20
3400/20 = 170 Rise
Best Going = 625 – 2R
= 625 – 2 x 170
= 285
2400/285 = 8.421
/8 = 300 (15 Diff)
2400/9 = (18.3 Diff)
Rise 170
Going 300

90. Calculate Stair Constrained Flight with Half Space Landing
Stair width 950mm
Preferred Riser 170mm
3400/170 = 20
3400/20 = 170 Rise
Best Going = 625 – 2R
= 625 – 2 x 170
= 285
2400/285 = 8.421
/8 = 300 (15 Diff)
2400/9 = (18.3 Diff)
Rise 170
Going 300
With all examples either answer will comply and you should consult with your client and/or Architect

91. Determine Steel Square Mathematically
40mm Margin

92. Determine Steel Square Mathematically

93. Determine Steel Square Mathematically
Stair Pitch = 29.54⁰
Zoom In

94. Determine Steel Square Mathematically
Stair Pitch = 29.54⁰
Margin Line

95. Determine Steel Square Mathematically
This angle must be the same Stair Pitch = 29.54⁰

96. Determine Steel Square Mathematically
This angle must be the same Stair Pitch = 29.54⁰
Sin Ѳ = Adjacent / Hypotenuse
= 40 ÷ X
X = 40 ÷ Sin 29.54
X =

97. Determine Steel Square Mathematically
This angle must be the same Stair Pitch = 29.54⁰
Sin Ѳ = Adjacent / Hypotenuse
= 40 ÷ X
X = 40 ÷ Sin 29.54
X =

98. Determine Steel Square Mathematically
Set Out For Steel Square Going
Going + Margin ÷ Sin Ѳ
= ÷ Sin 29.54⁰
= mm Ѳ

99. Determine Steel Square Mathematically
Set Out For Steel Square Rise Ѳ

100. Determine Steel Square Mathematically
Set Out For Steel Square Rise
This Angle must = Ѳ

101. Determine Steel Square Mathematically
Set Out For Steel Square Rise
This Angle must =
This Angle must = 29.54⁰
Y = 40 ÷ Cos 29.54⁰
Y = Ѳ

102. Determine Steel Square Mathematically
Set Out For Steel Square Rise
This Angle must =
This Angle must = 29.54⁰
Y = 40 ÷ Cos 29.54⁰
Y = Ѳ

103. Determine Steel Square Mathematically
Set Out For Steel Square Rise
Rise + Margin ÷ Sin Ѳ
= ÷ Sin 29.54⁰ = = Ѳ

106. reference
Kumar, G. Nagesh - Staircases