Table of contents:
Video: How To Make A Ladder Yourself. Part 1: Project
 Staircase design steps
 Basic terms

How to calculate stairs
 Direct marching
 Swivel staircase with platform
 Combined version of the swinging staircase with winder steps
In a country house, the staircase connecting the floors is almost the central link of the entire building. It depends on how correctly it is done whether it will be convenient to live in this house. It is believed that making a staircase is the lot of professionals only. This is partly correct. Without certain knowledge and skills, tools and materials, it is quite difficult to make and assemble a staircase on your own, and the final result may turn out to be far from professionally made samples. However, difficult does not mean impossible. If you are not a professional, but own the basic carpentry tools: a hacksaw, a plane and a chisel, then you can easily make a ladder yourself.
On the Internet you can find a lot of articles with recommendations for making stairs with your own hands. One common drawback is that, as a rule, they describe the process of making a staircase in a place that does not impose restrictions on its final dimensions.
Let us explain. There is a place where you need to make a staircase. There are requirements for the convenience of using this staircase  the slope, width and height of the steps. Further in these articles, it simply tells how to make a staircase, based on these requirements, completely disregarding the fact that the dimensions used in the manufacture will not always give a result that can physically fit into the existing dimensions of the room. But this factor is decisive! Even when designing a new house, if it is planned to make more than one floor in it, the place, shape and dimensions of the stairs will initially determine the entire layout of the future home.
Staircase design steps
Thus, the primary task that must be solved when making a ladder on your own is to determine the place in which it will be mounted. Here it is necessary to take into account many factors: the size and shape of the room, the presence and location of windows, the location of doorways and the type of floors. In addition, if the second floor is attic, that is, the walls are formed by inclined roof slopes, then the exit from the stairs should only be in a place where the distance from floor to ceiling is at least two meters. Otherwise, the person runs the risk of hitting his head on the ceiling.
The second stage will be the removal of all dimensions: the distance from the floor level of the previous one to the floor level of the next floor, the shape, width and length of the opening in the ceiling. A measurement error of a couple of centimeters can lead to disastrous results. That is why it is very important that the dimensions are taken by the person who will subsequently make the stairs.
The third stage is the choice of the shape and calculation of the main elements of the staircase: the width and height of the steps, the width of the staircase itself. It is at this stage that such dimensions are selected to ensure the maximum convenience of using the finished product. Based on the calculated data, a drawing is made.
The last stage is the direct manufacture and assembly of the ladder on site.
The following will describe how to choose the shape of the stairs and calculate its dimensions using a specific example. In the next article, we will tell and show you how to make and assemble it.
Basic terms
First you need to learn some of the terms that you need to know to calculate and manufacture stairs. Let's start by defining the types of stairs:

Marching. There are several types:
 straight  one straight flight of stairs  march. The easiest and most durable option. Takes up the most space in length. Suitable for installation along a long wall. In this case, it takes up almost no useful space;

rotary  consists of several, connected in one system of marches. Used when there is a lack of space. As a rule, the space under the stairs is used as auxiliary rooms  storage rooms, dressing rooms, etc. In turn, it is divided into several types:
 Lshaped (quarterturn)  two flights, connected by a platform at an angle of 90 °;
 Ushaped (halfturn)  two flights, connected by a common platform at an angle of 180 °;
 3section  halfturn staircase, consisting of three flights;
 combined  combines elements of two or more types.
 Helical or spiral. The steps are in the form of triangles or trapeziums, with acute angles directed towards the center. Takes up the least space, but the most inconvenient to use.
 Combined. Consists of several marches connected by elements of spiral staircases  winding steps.
Now let's move on to the elements of the staircase itself:
 The main element is a step  the horizontal part where the foot steps. It has the following characteristics: length, width and thickness. The width of the step should be within 250–300 mm. Length, it is she who determines the total width of the entire staircase, 8001200 mm, thickness 3550 mm.
 The riser is the vertical part supporting the step. To use the ladder conveniently, its height must be in the range of 150200 mm. Each riser gives rise to one step. The distance from the leading edge of the step to the riser is called the overhang of the step.
 The power element of any ladder is a stringer or bowstring. Kosour is a board with triangular cuts under the step and a riser that is rectangularly adjacent to it. Forms a staircase open from the sides. A bowstring is a rectangular board with grooves into which the side ends of steps and risers are inserted. Stringed stairs are stronger than stringed stairs, since the bowstrings form a single whole with steps and risers.
 Side rails. These are the railings and the elements under them  balusters and the like.
1  stage; 2  riser; 3  kosour; 4  winders; 5  support post; 6  handrail; 7  baluster
So, we figured out the definitions, let's move on to calculating the stairs.
How to calculate stairs
As mentioned above, the staircase should be such that the width of the steps is in the range of 250–300 mm, and their height, in fact, is the width of the riser, 150–200 mm. If you follow these rules, you will end up with a staircase with a slope of no more than 40 °, that is, one that will be comfortable to walk on.
There is a simple algorithm for calculating:
 We calculate the number of steps in the stairs. For this we take the first value  the height of the ceilings. The height of the steps is 150200 mm. Let's take something in between, like 175 mm. We divide the height of the ceilings by this value. We get the number of risers. When calculating, it should be borne in mind that the last step is, in fact, the floor level of the next floor. Therefore, the actual number of steps in a staircase is one less than the number of risers.
 We calculate the width of the steps at a given height. We take the length of the flight of stairs. We divide it by the number of steps. We get the width of the steps. If it falls within the range of 250–300 mm, then the problem is solved. If not, then we begin to select the size and shape of the stairs. Combining quantities, in addition to everything, can give more convenient options.
Example: we have a ceiling height of 2500 mm, an opening length of 4000 mm. We calculate the number of steps. 2500/175 = 14.28 risers. We round up to 14 pieces, while the height slightly increases to 178.5 mm  this is permissible. The number of steps is then 14  1 = 13 pieces. We calculate the width of the steps. 4000/13 = 307 mm. This is a preliminary calculation, from which we will start. In principle, the values obtained already give a good result. However, what happens if you play with the values a little, for example, if you decrease the height of the risers? The initial result was 14 risers with a height of 178.5 mm. To make them lower, you need to increase the number, for example, up to 15 pieces. Then the height of the steps is 2500/15 = 167 mm, and the width is 4000 / (15  1) = 286 mm. When using these dimensions, the ladder will be more convenient to use.
Let's move on to a specific task. We have the following premises:
Or here is a photo of the room itself:
Corner with window
Place of exit to the second floor
The same place from the height of the second floor
You need to make a staircase to the second floor along the far wall. In the room under the stairs, you can see it in the photo, there will be a toilet and a shower. To increase the distance from the right wall to the edge of the second floor floor and thereby make the staircase more gentle, part of the bathroom wall was removed. This resulted in an opening 3400 mm long. The distance from the floor level of the first floor to the floor level of the second is 2800 mm. The recommended staircase width is 900 mm. The option with a spiral staircase is not considered, due to its obvious inconvenience.
Let's model the main staircase options.
Direct marching
It can be done only along the wall, and, in front of it, it is necessary to leave a space of at least 700 mm. Such a staircase would look like this:
You can calculate the characteristics of such a ladder:
2800/175 = 16 risers or 15 steps
3400  700 = 2400 mm  length of the flight of stairs
2400/15 = 160 mm  step width
The selection of sizes can give little, therefore, in order to increase the width of the steps, you will have to make large overhangs, about 100 mm. The steepness of the stairs will be more than 45 °. It is still possible to climb such a ladder, but descending is inconvenient and even dangerous. The main advantage of this option will be ease of manufacture and small footprint:
Swivel staircase with platform
Let's calculate this option.
With a riser height of 175 mm, 15 steps are required.
The presence of a window on the adjoining wall brings its own limitations to the length of the first march  1700 mm. Taking into account the site  900 mm, 800 mm remains on the steps. It turns out that with a step width of at least 250 mm, no more than three steps can be made in the first march. The site is the fourth. In total, 15  4 = 11 steps remain for the second march. The total opening is 3400 mm. Taking into account the site, 3400 mm remains for the second march  900 = 2500 mm. The width of the steps then in the first march will be 2500/11 = 227 mm. This is already good, but maybe there is a better option?
Combined version of the swinging staircase with winder steps
Let's calculate this option.
With a riser size of 175 mm, we get the number of steps equal to 15. Obviously, the first flight of such a staircase will be similar to the previous version. Thus, there are 15  3 = 12 steps left for the winders and the second march. For the convenience of using the spiral part of the staircase, the optimal number of winder steps for turning by 90 ° should be equal to three. On the second march 12  3 = 9 steps remain. March length 3400  900 = 2500 mm. The width of the steps of the second march in this case will be 2500/9 = 278 mm. Received values  step width 278 mm, riser height 175 mm  ideally fit into the required ranges. Structurally, such a staircase is more complex, but it is much more convenient than a construction with an intermediate platform, and even more so a straight staircase. We will stop at this option. Let's draw the necessary drawings:
According to these drawings, we will make the stairs. This is described in the article "How to make a staircase yourself. Part 2: we make marches".