A staircase is a passage that allows people to smoothly climb up and down two spaces. It must have a reasonable structural design and require designers to have a thorough understanding and mastery of dimensions to make the design of the staircase convenient for walking. And it occupies the least space. From the perspective of architectural art and aesthetics, stairs are the visual focus and a major highlight that showcases the owner’s personality Stone stairs are an indispensable and important component of villa and mansion decoration. Stone stairs not only play a decorative role, but more importantly, their durability, and marble has become their best choice of material.
The slope and step size of the stairs
1. The slope of stairs
The slope of a staircase refers to the slope of the staircase segment, that is, the inclination angle of the staircase segment. There are two ways to represent the slope of stairs, namely the angle method and the ratio method. Angle method: Generally, the slope of stairs is between 23 ° and 45 °, with 30 ° being the appropriate slope. When the slope is less than 20 °, use a ramp; When the slope exceeds 45 °, a ladder shall be used. Ratio method: The commonly used slope for stairs is 1:2
2. Step size of stairs
The step size of stairs includes the width of the tread and the height of the riser. Tread: The horizontal part of the foot when walking. Kick surface: The vertical part that forms the height difference of the step. Empirical formula: 2h+b=600-620mm or h+b=450mm, where h represents the height of the riser; B represents the tread width.
In construction projects, the width of the tread is generally 260-320mm, and the height of the tread is generally 140-175mm. In residential buildings, the width of the tread is generally 260-300mm, and the height of the tread is 150-175mm, which is more suitable. Schools and office buildings should have a gentle slope, with a typical tread width of 280-340mm and a tread height of 140-160mm.
When the depth is limited, to make people more comfortable when going up and down stairs, without changing the slope of the stairs, the method of protruding the tread and tilting the tread can be adopted to solve the problem.
The width of the staircase segment and the width of the platform
1. The width of the staircase segment
The width of a staircase segment refers to the horizontal distance between the centerline of the handrail on the side facing the air and the centerline of the handrail on the other side of the wall (or against the wall).
2. Platform width
To ensure smooth passage and convenient handling of furniture and equipment, the width of the staircase platform should not be less than the width of the staircase segment. The open staircase floor platform should have a buffer space, with a width of not less than 500mm. Closed stairwell floor platforms are generally the same width as the middle rest platform, but must meet the local size requirements specified in the specifications.
The clearance height of the stairs
When determining the clearance height on a staircase, the calculation range of the staircase should start from 300mm outward from the leading edge of the front and last steps of the staircase, respectively. When a passage is set up under the middle platform at the bottom of the staircase, to meet the net height of the space below the platform of ≥ 2000mm, several treatment methods on the right side are often adopted:
The height of stair railing handrails
The height of the railing refers to the vertical distance from the leading edge of the step to the top surface of the railing.
The height of staircase handrails in general buildings is 900mm; When the length of the horizontal handrail on the platform exceeds 500mm, its height should not be less than 1050mm; The height of the handrails in kindergarten buildings cannot be lowered, and an additional 500~600mm high children’s handrails can be added.
Staircase design steps:
(1) Determine the form of the stairs;
(2) Based on the nature and purpose of the staircase, determine the appropriate slope of the staircase, choose the height h of the tread and the width b of the tread (2h+b=600-620mm);
(3) Determine the width B of the staircase segment based on the opening of the stairwell and the size of the stairwell;
(4) Determine the number of steps. Divide the height H of the building by the height h of the floor to obtain the number of steps N=H/h, which should be an integer.
(5) Determine the horizontal projection length L of the staircase segment based on the initial tread width b.
(6) Calculate the staircase clearance to meet the requirements for clearance height.
(7) Finally, draw the floor plan and section of the staircase.