The calculation method and formula for stairs are as follows: first, select the tread width 'b' and tread height according to regulations. Divide the room height by the tread height to get the number of steps, rounding down to integer 'N'. Then, divide the room height by 'N' to get the tread height 'h'. Multiply the tread width 'b' by '(n-1)' to get the total stair length, which is then divided into two sections. For residential stairs, choose an integer between 250-280 for tread width and 150-165 for tread height. For public stairs, choose an integer between 300-350 for tread width and approximately 150 for tread height.

The staircase is a passage that allows smooth transitions between two spaces. Its structural design is rational, with each step of a standard staircase being 15 cm high and 28 cm wide. Designers must have a thorough understanding and mastery of dimensions to ensure that the staircase design is easy to navigate while occupying minimal space. According to practical observations, the height of the steps should be less than 18 cm, and the width should be greater than 22 cm.