To calculate the stairs at home, you need to consider certain parameters.
The staircase of the second floor should be such as to ensure safe ascent/descent, that is, in addition to the area and layout, you need to know the following parameters:
- Ceiling heights at installation levels;
- Location of doorways in relation to the interfloor area;
- Location of walls between rooms and load-bearing structures.
Knowing these data will allow you to choose the optimal design of the stairs for a particular room. After selecting the design, a calculation should be made for this room.
How to calculate a wooden staircase
The step length is taken as the basis, the average value is 63 cm, but for an individual calculation, the step length of the future owner of the stairs is needed because everyone’s height is different, and what is comfortable for some may be inconvenient for others. Step length is measured with a ruler or tape measure – this is the value from the middle of the foot of one leg to the tips of the fingers of the other. The distance varies from 55 to 64 cm.
The next parameter is the depth of the step, which lies in the range of 25-30 cm, depending on where the structure is installed. The number of steps for each march must be odd. Starting the ascent with the right foot, with an odd number of steps, the person ends the ascent also with the right foot. 3. The slope of the ladder structure (the value between the horizontal surface and the stringer or bowstring) depends on its purpose and the area of the room. For attic and basement stairs, it is 45-53 degrees, for intra-apartment, residential or public buildings – 41-36 degrees, for outdoor – 20-35 degrees.
The procedure for calculating a single-flight staircase
First determine the number of steps. At the same time, the height of the room (260 cm, measured with construction tape from the floor to the ceiling) is divided by the height of the riser (17 cm). 260:17=15.3. So, in one march, there will be 15 steps. Since the number is fractional, it is necessary to eliminate the difference in height: either the last or first step is made a little higher, or a small elevation is built under the stairs.
Then the depth of the tread is calculated, it should be at least 28-30 cm, which corresponds to size 45. The step length is 62 cm, we subtract two riser heights from it – 62-17×2 = 28 cm.
Now you need to calculate how much space the structure will take and the installation angle. We recall geometry and find tables of trigonometric functions. The projection of a flight of stairs onto a plane is a rectangle, everyone knows how its area is located. Multiplying the length of the sides, we get the area. One side is the width of the steps, the second is the projection of the length of the march. We calculate the second value as follows: we multiply the depth by the number of steps 28×15 \u003d 420 cm. The first value is the width of the stairs, which on average is 90 cm, along with the fence.
We proceed to the calculation of the structure, that is, we calculate the length of the march – the hypotenuse in a right triangle. One of the legs is the height of the room, and the second is the horizontal projection of the span. C2 = a2+b2=2602+4202. The desired value, that is, the hypotenuse is 494 cm, if fractional parts are obtained, they are not taken into account.
The angle of inclination is calculated using the trigonometric formula: cos=a\c. With these inputs, the angle of inclination is 34 degrees.