How to calculate the ladder on your own

Before you begin to install stairs in a country house or apartment, you need to calculate its main parameters using standard technical standards.

There are two types of stairs: with staggered steps and screw.

Below is a procedure how to calculate the ladder of both types.

Method for calculating the ladder with the staggered steps

Calculation of the staircase with the blind steps is performed using the following technical standards:

The steps usually have dimensions of 15x30, i.e. The step height is 15 cm, and the width is 30 cm;

- The above parameters of the steps allow to make a ladder with a gradient of the march in the ratio of one to two;

- the width of the ladder must be at least one hundred and twenty cm;

- the width of the platform must be not less than the width of the ladder itself;

- the number of steps in the march usually ranges from five to fifteen.

But sometimes there is a situation where pre-defined technical parameters can not be used because of the unconventionality of the ladder being mounted.

How to calculate the ladder in this case?

For this case, there is another method for calculating the ladder with the staggered steps.

To use this method, it is necessary to familiarize yourself with the following terminology:

- width of tread - defines the distance between the leading edges of adjacent steps and is denoted by the letter "b";

- the height of the riser is the height between the planes of the two steps and is denoted by the Latin letter "h".

To determine the height and width, proceed from the following expression:

2 х h + b = 60 - 65 cm

Those. The sum of the double height of the riser and the width of the tread must be from sixty to sixty centimeters.

Also, you can use two more arithmetic expressions to calculate the ladder, the names of which speak for themselves: "convenience formula" and "safety formula".

The "comfort formula" has the following relation: bh = 12 cm.

"Safety Formula": b + h = 46 m.

In addition to the above calculation of the parameters of the future ladder, it is necessary to focus on the following rules:

- the width of the ladder march should not be less than one meter;

- if the ladder has more than three steps, then it must be equipped with handrails;

- the distance between the wall and the ladder march should not be more than five to six cm;

- The maximum load that the ladder must withstand is from one hundred and eighty to two hundred and twenty, and the railing is not less than one hundred kg.

Method for calculating the spiral staircase

Spiral staircases are mainly used in those rooms in which it is necessary to save a useful area.

At first glance, the calculation of the spiral staircase seems complicated. But, nevertheless, it is within the power of everyone, even one who is not too strong in mathematics.

For greater clarity, a method is given for calculating a ladder, namely a screw, using a practical example.

At once it is necessary to make a reservation that the optimal size of the spiral staircase width should be 0.8 - 0.9 meters.

And so, for example, it is necessary to calculate a ladder having a width of 0.85 meters and a height of 2.7 meters. In addition, this ladder should have a central rack with a diameter of 0.25 meters, a step width of 0.2 m. The height of one turn is 2.05 m.

First, it is necessary to determine and draw the overall diameter of the entire structure, proceeding from the expression: 0.85 x 2 + 0.25 = 1.95 meters.

That is, the total diameter is equal to the sum of the double width of the ladder and the diameter of the central pillar.

In the received circle it is necessary to enter another circle, proceeding from the following expression: 0.85 / 2 + 0.25 / 2 = 0.55 m.

Where 0.85 is the width of the step, 0.25 is the diameter of the central column.

The resulting circle is the trajectory of a person's ascent.

Next, determine the number of steps per turn from the relationship:

2 x 3.14 x 0.55 / 0.25 = 13.816

Where 3.14 is the number of pi.

We round up to 14 steps.

Then calculate the height of the steps: 2.05 / 14 = 14.64 cm.

Where 2.05 is the height of one turn.

Determine the total number of steps according to the expression: 2.7 / 0.1464 = 18.44. We round to 19.

At the last stage, according to the procedure for calculating the ladder with a screw march, calculate the final height of the step: 2.7 / 19 = 0.142 m.