You will need
• Model the stairs, her measurements, special calculations.
Instruction
1
Make measurements of the space where will be located the future steps. Determine the width of the tread (distance between the front edges of the steps) and the height of the riser (the distance between the upper surfaces of the step). The optimal size of the feet – when the sum of the width of the tread and twice the riser height equal to 60-65 see
2
Apply in the calculation of the formula provided (tread width – the height of the riser = 12 cm) and formula safety (tread width + height of the riser = 46 cm.)
3
Note in the calculations of basic rules for the design of stairs:

- width of the step shall not be less than 1 m;

all marches (units of degrees to turn, bend or landing) with the number of stages is greater than three, must be equipped with railings;

- if children are present, the distance between the uprights of a handrail should not exceed 10 cm, and the distance between steps is 12 cm.

- staircase must withstand the load not less than 200 kg, and the railing – 100 kg;

- the height of all the steps should be the same;

- the distance between the wall and the March should not be more than 5 cm;

the radius of curvature of the curved stairs in the middle line should not be less than 30 cm;

- the level of the last stage coincides with the floor level.