The height of the placement of cognac determines the static appearance, its specifications and architectural specificity. When drawing up a project, it is very important to accurately determine correct proportions designs. To achieve best results, it’s worth better understanding how to calculate the height of the roof - this, in fact, will be discussed in this article.
What should you consider when choosing the height of the ridge?
The channel is an edge gable roof, located horizontally, which is formed where the vertices of inclined planes connect. By calculating the height of the ridge with overestimated or underestimated values, you can not only spoil the architectural picture, but also create problems that in the future will affect the operation of the entire house.
To better understand what the ratio of the roof to the house should be, you need to imagine the roof in the form of an equilateral triangle. This execution is the most common. There are, of course, asymmetrical double-sided roofs, whose slope areas differ. But since the slopes of opposite sides are often equal, the height of the ridge of a gable roof is determined in a standard way.
An equilateral triangle is divided into two equal parts. The line running from the top of the triangle to its base is the axis of symmetry, and, in our case, the height of the ridge.
Influence of atmospheric phenomena
The climatic factor is a variable that should be taken into account when designing a roof.
TO atmospheric phenomena that will affect the height of the roof include:
- Wind power. In regions characterized by fairly frequent gusts of wind, it is better to erect flat and low-slope roofing structures with a slope of up to 10 degrees. Where the winds are moderate, the ridge can be installed at any height.
- Precipitation amount. Precipitation is always considered the most likely threat, causing leaks that lead to gradual destruction rafter system and the entire roofing pie. For example, from roofs with a slope of 45 degrees significant precipitation falls faster than from flatter ones.
- Volumes of snow precipitation. In regions where heavy winter precipitation falls year after year, it is best to construct a roof with a slope exceeding 45 degrees. In this way, faster snow melting can be achieved, which cannot be said about low-slope roofs, where most of the snow will have to be cleared off manually.
All this data can be obtained from your local weather service. Alternatively, you can get them yourself in the literature on building climatology SNiP 23-01-99 or from the available zoning maps SP 20.13330.2011.
How to calculate when installing an attic in a gable roof
Calculating the roof height will also depend on whether you are going to install attic space. If you are planning to do so, the attic space will be separated from the house by a ceiling. The attic can be residential or non-residential. Design with residential attic, as a rule, has a broken pattern, in which the rafter system will consist of two tiers.
When determining how high the roof ridge should be if there is an attic, you need to calculate two values: the height of the lower segment of the roof and the height of its top, resting on the lower tier. The lower tier often has a height of 2.0-2.03 meters.
In addition, you need to take into account the height of the tallest owner of the house, adding 30-40 cm to this figure, so that it is convenient and safe to move around in the room. Top dimensions sloping roof may be favorites, they will be determined by the individual preferences of the owners.
The height of the ridge of attics that will not be intended for living will depend on the standards fire safety.
Another option for an attic-free room is with a space combined with the main box. As a rule, its location is at the same height as the ceiling of the previous floor. Attics of the attic type are constructed according to a gable scheme, and the mauerlat must be laid on walls higher than 1.4 meters. In the case of a half-attic, the height of the ridge begins to be counted from the bottom edge of the mauerlat.
We make calculations based on the type of roofing material
Another factor that influences how to calculate the height of the ridge of a gable roof is the type of roofing material used.
To select a suitable roofing covering, taking into account the height of the ridge, you can use some rules:
- The smaller the individual roof components, the higher the slope of the pitched plane. A large number of joints most often causes moisture to get under the roof, so in such cases it is very important to make the precipitation converge faster.
- The lower the pitch of your roof, the fewer seams it should have. In such situations, it is best to cover the roof with large-sheet and roll materials.
- The greater the mass of the covering, the steeper the roof slope should be. It turns out that the higher the ridge, the less force is exerted on the rafter system and the ceiling.
Before calculating the height of the ridge, keep in mind that a roof with a high ridge will be somewhat more expensive. For example, a roof with a slope of 45º requires one and a half times more material than a structure with a slope of 7-10º, and a roof with a slope of 60º will require twice as much money.
As a rule, the distances of suitable slope units are indicated by roofing material manufacturers in the instructions. Such recommendations are worth considering if you expect your structure to last as long as possible. Taking into account the recommended slope, the width of the eaves compartments and the dimensions of the house box, you can easily determine the height of the ridge. Basically, the height of the roof in relation to the width of the house has a more or less standard ratio. However, other methods are used when planning roofs.
To indicate the angle of the slopes, degrees, percentages or decimals, including the height of the ridge, and after the fraction - half of the span being covered. On a construction site, it is easiest to use the third option. Percentage expressions are used much less frequently, because craftsmen and home craftsmen only get confused in them.
Installation of layered rafters is carried out on an already mounted ridge girder. This means that you need to know in advance the height of the ridge girder. If you know the height of the ridge, then you don’t have to look at the project from time to time. Using the measurement method, the center of the front wall is calculated. In this place, a block or pole is clearly fixed vertically. From the top edge of the Mauerlat pre-mounted on the wall, the size we determine is counted upward. It will need to be taken into account at the time of construction of the rafter system.
How to calculate roof height
For correct calculation the height of the roof ridge, and also to ensure that the height of the roof in relation to the height of the house is selected correctly, you can use one of the many calculator programs that can be easily found on the Internet. They are very easy to use, and the calculation results are fast and accurate.
The only negative is that it is not so easy to check the finished calculation results without the ability to clearly demonstrate the planned roof structure. In addition, if you accidentally enter the wrong number into such a calculator, you will only be able to find the error during construction. Therefore, it will be much better if you check all the numbers and design features before the calculations, so that a minimal error in the future does not cost you significant unplanned costs.
In order to calculate the height of the roof ridge as accurately as possible, you will need knowledge of trigonometry, as well as the ability to build buildings to scale according to the diagram. For this you can use either a monitor or a simple sheet of paper.
Graphic and mathematical methods for determining the height of the ridge
- Mathematical - in this case, the size is calculated using the formula for determining the length of one of the sides of a right triangle.
- Graphic - you will need to create a scale diagram of the roof.
Using mathematical method calculations, you need to take the formula a= b × tgα, where a is the height of the ridge; b – half the span width; tgα – slope determined by the owner of the house based on technical requirements and recommendations of the roofing material manufacturer.
Graphical method involves obtaining dimensions at the intersection of the center of the roof and the slope line running at a certain angle from the last point of the eaves overhang.
It is worth noting that the listed methods can determine the rise of the roof, but not the entire height of the ridge. These indicators are determined by installation technology upper parts rafters When using hanging rafter systems, the height of the ridge will be the same. The same applies to layered systems, in the case where the top of the rafter extends beyond the line of the ridge girder.
When rafter legs extend beyond the purlin, then 2/3 of the thickness of the board or timber used during the construction of the rafter system must be added to the height of the roof. It is worth considering that the depth of the cut reduces the thickness of the material by a third.
As a rule, the calculation does not take into account the sheathing laid on the rafters. Minor deviations are inevitable during the construction of the roof, which can reach 5-7 cm - this is normal, since negative consequences does not lead.
Using a practical calculation method
Whatever the height of a one-story house to the roof, you can determine the height of the ridge practical method. It is used in calculations by North American carpenters, whose work is focused on the construction of low-rise buildings. frame houses. However, this process is fundamentally no different from the work carried out by craftsmen in other countries.
U this method There is a technological feature: the installation element of the lower heels of the rafters to the base is carried out using the cutting method. The rafters rest on a ridge board. If this condition is not met at the stage of creating a diagram and obtaining calculations, the slope will become different, and this is best avoided when determining the extreme slope parameter recommended by the manufacturer of the roofing material.
At the basis of the calculations, we again have an equilateral triangle divided into two equal parts. We have the width of the house box and the slope.
The sequence for determining the height of the ridge will consist of the following actions:
- First of all, we create a scaled diagram and indicate on it the exact dimensions of the house box. It is best if the scale is 1:100, at which 1 cm will equal 1 meter in scale. If for some reason it is inconvenient for you to work with such a scale, you can choose your own, larger or smaller.
- Let's determine the center of the span, and from there we'll draw a line upward, which is the axis of symmetry of the roof.
- Using a protractor from the corner of the house box, mark the angle of inclination of the roof being created. To do this, draw a line based on the marked angle.
- To determine at what height you will need to place the ridge board, you should rely on the data obtained as a result of the intersection of the axis of symmetry of the roof with the slope line of the slopes.
- We mark the outline of the ridge girder and the post on which the girder will rest. Their line of symmetry should coincide with the line of symmetry of the roof. To do this, you will need to set aside half the thickness of the ridge board in both directions from the axis and draw lines.
- Line of the lower side of the triangle, diagonal and adjacent side edge the ridge girder together with the stand will point to the triangle we are defining, whose vertical leg will be equal to the height of the roof.
- We make the lift less by a third of the thickness of the board - that is, to the depth of the cut of the lower element of the rafters.
- From the height we have determined upward, we count the width of the ridge board, and draw the ridge purlin, after which we draw the ridge post.
- Now, according to scale, we draw the rafter leg, taking into account that it will have a drawdown of a third of the width due to cutting. To make the work easier, draw a straight line parallel to the diagonal, 2/3 of the rafter thickness.
In other words, the height of the ridge is the sum of the rise of the roof and 2/3 of the thickness of the rafters. In reality, you won't get perfect accuracy anyway. However, a minor error is considered to be negligible. Minor flaws are allowed according to the construction standards for constructing a structure made of wood, specified in the collection SP 64.13330.2011. An ideal miscalculation is characterized by taking into account physical processes for compression and crushing wooden elements systems.
One of the main components of a building is the roof. Without it, the structure will not last long and it will be impossible to live in it. The roof has complex design and requires a responsible approach during design and installation. It is necessary to choose correctly not only its shape, but also the angle at which the slopes will be located. The angle will depend on how the ridge height is calculated. How to find out this size? This will be discussed in the article.
What affects the height of the skate
The roof ridge is the highest point of the roof. It is a horizontal stiffener. The element is located at the place where the slopes come to one point. The height of the ridge is one of the fundamental factors that can affect the shape of the future roof. Incorrect choice ridge position may result in the roof being unable to support the intended loads. This will also lead to a deterioration in the appearance of the roof. Not all personal ideas in relation to the roof structure can be translated into reality, since they may contradict the elementary rules for choosing the height of the ridge. The calculations take into account several main factors that directly affect the height of the ridge. These include:
- atmospheric phenomena;
- method of using the under-roof space;
- selected roofing decking.
These parameters cannot be taken into account separately from each other, since they are directly interrelated.
Atmospheric phenomena
It is impossible to adjust the climate to the shape of the roof and the height of the ridge, so you have to take into account what conditions exist in a particular area. Often they are the determining factor in how many slopes the roof will have and what their angle of inclination will be. If the house is built in an open area where there are no forests, then we can safely talk about high wind loads. When choosing a large angle for the roof, you may encounter the fact that it will become a good sail that can be easily demolished when in good spirit. That is why for such areas the slope angle is selected with a value of up to 10°. There is no need to worry about snow accumulation on the roof. It will simply be blown away by the wind.
Water tends to linger on flat surfaces. Therefore, for areas where there is often heavy rain, you will need to select an acute angle, which can reach 30 degrees or more. In this case, water will be able to flow freely without seeping through the cracks. If this happens, then the rafter system will become damp and eventually dry out or be destroyed by fungus. When you plan to build a home near a forest where there is often snow, the roof angle can be chosen up to 45°. In this case, the height of the ridge will be greatest compared to the two previous cases. Thanks to this angle, less snow will be retained, and it can also be easily removed from the slopes.
Advice! Information about what angle, and therefore the height of the ridge, will be relevant for the roof can be provided by the local weather service. It is with its employees that you can clarify the prevailing weather conditions.
Roof space
This is the next factor that directly affects the height of the ridge. The space under the roof can be used in various ways. Previously, it was used only to organize a cold attic. Various things or food could be stored on it. In this case, the space was separated from the main room only by beams on which the trim was attached. There is also an option for a roofless design. In this case, there is no partition between the under-roof space and the living space. This also affects what height will be chosen for the roof ridge.
The under-roof space, which is separated from the living space, is used not only for storing things, but also as a living space. In this case it is called an attic. Living space It should be of such a height that it is comfortable to move in it without slouching. This factor affects the height of the ridge. Typically, for these purposes, the figure of 2.3 meters is taken as a basis. Measurements are taken from the lower tier on which the roof is mounted. In this case, it is important to take into account the largest growth of the residents. A margin of 40 cm is added to it so as not to catch your head electrical devices and partitions.
When the attic is unused, then its height is determined by fire safety standards. The height of the ridge in this case should be such that there are no obstacles if it is necessary to move inside in an emergency or during maintenance of the rafter system. The height is based on a figure of 1.6 meters in height, which will be enough for a person. The width of the passage must be at least 1.2 meters. If the roof is multi-slope and has a complex rafter system, then the dimensions in the spans can be reduced by 40 cm.
In the case where the under-roof space is combined with the main room, the height of the ridge can be made smaller. This will reduce heating costs and also bring comfort. Typically, the space near gable roofs is used in this way. In such a design, the walls must be at least 1.4 meters high. In this case, the reference point for the height of the ridge is the lower part of the Mauerlat. This type of roofing system will be especially relevant in areas where there is a large amount of wind. The load is distributed in the best possible way.
Note! Attic space is not provided in various outbuildings. This will incur additional costs, but often will not be of practical value.
Roofing decking
Each roofing finish requires or allows a certain angle of inclination, which directly affects the level to which the ridge will be raised. There are several factors regarding decking that affect the slope angle. These include:
- size of coating elements;
- roof height;
- coating weight.
The size of the coating elements affects the number of joints between them. The smaller the individual roof elements, the more seams there are between them. If you make a roof with such a decking with a minimum angle, then there is a high probability that moisture will seep into the cracks and cause harm to the roofing system. How larger sizes individual elements for the roof, the smaller the angle of inclination can be made, and therefore the smaller the height of the ridge. Any roof covering has its own weight. Ceramic tiles are much heavier sheet material. To properly distribute the weight that the decking has on the roof and walls, you need to choose the right angle and location of the ridge. General rule states that the heavier the flooring, the sharper the angle should be.
Note! It is important to understand that as the roof angle increases, the area of each slope also increases. This means that more material will be needed than for a roof with a lower slope.
In construction, it is customary to indicate the roof angle in degrees. There are other options, including percentage or fraction. For the latter, the height of the ridge is indicated in the numerator, and the denominator is a figure equal to half the span that will be blocked. On construction site It is not customary and incorrect to walk around with a large protractor to select the required angle. Fractional notation is usually used. It is worth understanding that the installation of layered rafters is carried out on the ridge girder, which is installed. This means that it is important to know the height of the ridge before starting the process. Setting aside this size on the work site is quite simple. It is enough to determine the middle of the wall on which the pediment will be mounted. A wooden or other plank is installed at this point. Using a plumb line or level, it is set vertically. Using a tape measure, the height at which the ridge will be located is set off from the top of the mauerlat.
Calculation methods
Two main methods of performing the calculation have been developed:
- graphic;
- mathematical.
Each of them can be simple in their own way, so they are worth taking a closer look at.
Mathematical
To calculate the height of the ridge beam mathematically, you will need to remember the school geometry course. It is easier to carry out calculations if you imagine the roof structure in the form of simple geometric shapes. Most often, a gable roof is an isosceles triangle. If you draw a height in it, you get two right triangles. It is the height that is sought, since the ridge will be at its top. This height is the leg of a right triangle, so you can use a simple formula to calculate it. The length of the smaller leg will be equal to half the length of the wall on which the pediment will be installed. If you determine in advance the angle of the roof slope, then you can use the Pythagorean theorem to determine the length of the larger leg or height.
For example, if it was determined that the roof angle for a 10x12 meter house will be 30°, then you can simply determine the height at which the ridge will be located. For these purposes, we find out the length of the second leg by dividing 10 by 2. According to the Pythagorean theorem, this value must be multiplied by the tangent of the selected roof angle. The latter for 30° will be 0.577. If you multiply 5 by 0.577, the result is 2.885 meters. It is at this height that the ridge beam should be located. You can learn more about the calculations from the video below.
Graphical method
The accuracy of the graphical method will depend on the skills specific person by sizing by eye. To do this, draw an image of the roof in the form of an isosceles triangle. It is important to maintain the specified scale. The easiest way is to use a piece of squared paper for these purposes. You will need to draw a right triangle. Half the length of the wall is known; the angle of the roof is also known. The leg is drawn to scale, and the angle of the roof is marked using a protractor. After this, you can connect the resulting lines with the second leg and measure it using a ruler. After this, according to the scale, the conversion is made to the real value.
Note! The graphical method does not provide the same accuracy as the mathematical one, so it is not recommended to use it for serious objects.
Summary
There are a large number of online calculators available to calculate ridge height, but none of them are available on the construction site. That is why it is important to be able to find a specific meaning only using your knowledge. The article showed two methods of how this can be done.
Options for calculating the roof ridge area have their own characteristics. You should know the following values:
- The sum of the entire length of the skates;
- Width and length of the structure;
- What is the number of ridges and total length;
- How many stingrays are present and what type are they.
When covering the ridge with soft and flexible materials, use the following formula:
Roof area = (2 x overhang width + length of the entire house) x (2 x overhang width + width of the entire house) / cos (angle slope). With all this, the entire coverage area must be taken into account, and valleys must be calculated separately. Then, the amount of material used will depend on the type of metal tile used.
The structure of a gable roof is almost similar to structures of other pitched types.
To cover the roof use:
- Slate;
- Metal tiles.
Roofing units contain units for ventilation passages of shafts and chimneys that go through the roof covering. Individual way the construction of units and their quality directly depend on the type of roof.
A gable roof consists of the following structures:
- Rafters;
- Lathing;
- Overhangs;
- Mauerlat;
- Thermal insulation;
- Horizontal ribs;
- Waterproofing;
- Racks;
- Endovy.
For calculation soft roof, take into account:
- Structural elements;
- Calculation of the height of the roof and rafter system;
- Take into account the overhangs of the cornices, overlaps and overlaps of the ridges.
The entire calculation will be exactly the same as for a gable roof, but there are some differences. The main difficulty is that this roof will have more than one angle of inclination, and before starting the calculation, we recommend that you use the “golden ratio” rule, which will allow you to fit the contour of the roof into a circle. This action will help you avoid the most common drawback: if the calculation is done incorrectly, the roof will look very ugly.
Pay attention Special attention calculations, because the entire reliability of the structure, its long service life and aesthetic appearance will depend on this. Do the calculations in advance, otherwise you may lose a significant amount of money and waste time redoing all the shortcomings.
It is important to know that its angle of inclination and area also matter. The calculation of height is influenced by factors such as the climatic conditions of the region of residence, roofing and sheathing material, personal wishes, etc.
For example, on slopes with a low angle of inclination, a lot of snow accumulates in winter, which can lead to a roof break.
However, with a high ridge, the roof becomes more vulnerable to strong winds. Not only the practical indicators of the design (strength, durability), but also the aesthetic ones depend on the dimensions.
Design features and main parameters
The roof protects the house from influence external environment, heat loss and gives the building a finished look, so it is important to correctly calculate all the dimensions of the parts, including the height.
- angles and number of slopes;
- how the attic space is planned to be used;
- climatic factors of the region of residence ( average speed wind, amount of precipitation in winter, etc.);
- personal preferences;
- characteristics of sheathing, roofing and building materials.
You should also take into account the parameters of the roof rib (ridge), since the structure of the rafter system and sheathing largely depends on it.
In addition, it affects the overall height. If you do not know the characteristics of the ribs, it will be difficult to calculate the optimal roof area, and as a consequence, the number building materials for further work.
The type of insulation also affects the parameters. If all calculations are carried out correctly, you can build not only a strong, durable roof, but also save on the purchase of materials.
You will know them exactly required amount and you won’t have to overpay for extras that won’t be useful later.
The ridge purlin is used as a joint connecting two roof slopes (like gable roof).
The rafters, sheathing and roofing material on both sides, so it should be the strongest in the entire structure.
Make a calculation optimal height the ridge can be built according to the following rule: the length of the ridge is equal to half the length of the span of the house, multiplied by the tangent of the angle of inclination.
Also, a correct calculation of the roof height cannot be made if you do not know its type.
In most cases, the slope angle varies from 8 to 45 degrees. The smaller the angle, the greater the load on the rafter system (especially in winter period and when carrying out work on the roof itself), therefore, additional strengthening and adjustments in calculations will be required.
However, as the angle increases, the cost of construction increases.
The size of the rafters is determined from their cross-section and length: the larger they are, the greater the load the system can withstand.
Calculations for different types
At pitched roof It is easiest to carry out calculations and installation; this does not require much experience in construction.
First you need to measure the width of the entire building in centimeters. Use for measurements building level and roulette.
After this action, you need to divide the resulting value by the second number of the planned aspect ratio.
For example, if you plan to build a structure with a ratio of 1:4, then the width of the house (in cm) needs to be divided by 4, the result is best option heights with a small error.
You also need to take into account the ratio of the height of the roof to the height of the house.
With a gable roof it can be a little more difficult, because you need to know exactly the size of the angle of inclination.
For this case, the following formula is applicable: half the value of the width of the building is divided by the tangent of the angle of inclination.
For example, the tangent of an angle of 40 degrees is 0.8, therefore half the width of the building is divided by 0.8.
The hip roof is gaining popularity today due to its strength, attractive appearance and the ability to easily install doors and windows.
There are two types of such roofs:
- hipped hipped roofs. They have the same area, shape and length for all slopes in the structure. They perfectly withstand strong winds and can withstand high loads;
- hip hipped. They have a complex structure, consisting of two trapezoidal and two triangular slopes (hips). The costs of purchasing materials and construction are high, but this design allows you to build an attic with windows under the roof. This type is very vulnerable to winds, so in regions with prevailing winds, additional protection costs will be required.
To calculate the optimal height hipped roof you can use the formula for gable. Only the width of the house should be divided not by 2, but by 4.
The complexity of the calculations is due to the more massive structure under which supports must be installed. Standard height for such roofs it is about 2.5 m, with an error of 0.5 m.
The most difficult to calculate is mansard roof or a hip roof (popularly called a “broken roof”). The design includes two slopes with kinks.
As a rule, such roofs are used if it is planned to make an attic out of the attic.
Initially, it is necessary to calculate all the angles of inclination. You can use the formula for a gable roof.
It is important to adhere to the following rule: the lower angle should be more than 40 degrees, and the upper angle from 15 to 40.
A correctly calculated ridge and roof height directly affect its appearance, durability and strength.
If you are not sure that you can produce it yourself correct calculations, then seek help from a specialist.
What is important to know for calculations and the dangers of errors
- Types and shapes of modern roofs
- Ridge run and slope angles
- Roof height calculations different forms
- Roof calculation using online resources
- What to consider when starting roof calculations
The final stage of building any home (whether it is a spacious main dwelling or a small country house) is the arrangement of the roof. It is this that gives the exterior a presentable and complete appearance. But at the same time it performs a very important function - it retains heat, creates a cozy, most comfortable and pleasant atmosphere inside. It is this element of any structure that, without exaggeration, is called one of the most important.
What does the height of the structure depend on and what is taken into account when performing pre-installation calculations
It is especially important to know how to calculate the roof height for a house, and to understand exactly how to do it correctly. That is why you need to spend some time studying this issue. Inaccuracies in pre-installation calculations lead to serious problems that are too difficult to deal with later. Often, to eliminate errors, you have to start roofing work all over again.
For example, if the slopes are made with a small angle of inclination, then winter snowfalls will cause serious damage to such a structure (due to the accumulation of snow, there is a risk that the roof will break). It is logical to assume that you can simply do a high skate and all problems will be solved. But this is not true either, because a roof that is too high is most vulnerable to gusts of wind.
- general square footage of the structure;
- climatic conditions (as you may have guessed, sloping roofs, which are optimal for warm continents, are not recommended in regions with snowy winters);
- material for roofing, as well as lathing;
- selected form;
- height of the main building;
- personal preferences and tastes of the owner.
The design parameters are largely influenced by a number of other factors, for example, there is a direct dependence on the layer the required insulation or installation of snow guards. The dimensions of the ridge are related to the characteristics of the rafter system, but at the same time they can increase the total area of the roof and the amount of materials required for its arrangement.
Everything described above confirms the fact that the strength of the structure, the durability of its operation, aesthetics and harmony depend on the size of the roof. appearance the buildings.
What are the common types of modern roofing structures?
The type of roof has the most direct impact on the calculation and the formulas used for it, as well as on the amount and, therefore, on the consumption of material that needs to be purchased for roofing.
Today the following structures are most often erected:
- single-pitched (it is preferable to use it for outbuildings);
- gable (most popular for residential buildings);
- hipped. Also an excellent choice for residential buildings. There are a variety of options here: spectacular hipped ones (their characteristic feature is the same size and shape of all slopes) or complex hip ones (their feature is the participation of two triangular hips and two slopes with a break (trapezoid shape));
- attic (consists of two slopes, but always with a break). This break allows you to increase the area of the attic.
Ridge and determination of rational slope angles
To calculate different roof shapes, the size of the ridge is used. This name refers to the upper, horizontally located edge of the structure, which was formed at the intersection of two roof slopes (inclined planes).
There is a ridge on all types of roofs, except hipped and domed ones.
If the design , then there is only one, but if it is complex, then two or more skates are formed. During the construction of the roof, the rafter legs rest on the ridge purlins, and based on what roofing material is chosen for the final covering, the base of the ridge is selected.
Knowing how to calculate the height of the roof correctly is necessary to build a reliable and durable structure, as well as to predict preliminary construction costs and plan a budget. When calculating the rational angle of inclination, the material from which it was decided to lay the roof is taken into account: some roofing coverings can be laid at an angle of up to 90 degrees, while others can only be laid at an angle of 15 to 60 degrees.
When choosing with what slope of planes to choose a roof for your home, you need to take into account functionality, the general appearance of the resulting structure (after all, you want to get an aesthetic structure) and climatic conditions. As practice shows, for European countries ideal solution you can call the angle 35-40 degrees.
Examples of calculations that are easy to do yourself
Basically, if we are talking about simple designs roof, then you will need very little to calculate the height of the roof: a calculator and several well-known principles from the basics of geometry, which are taught in the school curriculum.
We take the basic principle of calculation from the rule that the length of one leg is right triangle will be equal to the length of the other if multiplied by the tangent of the angle formed with the base.
- we measure the width of the building (let’s say we have a four-meter house);
- we take the angle equal to 35 degrees (as the recommended optimal option for European latitudes);
- We calculate the tangent, it is obtained for a given angle of 0.7002;
- 4 meters * 0.7002 = 2.8 meters.
If a gable design is chosen, then in this case the height of the ridge is also very simple to calculate: the width of the house can be divided by “two” and then multiplied by the tangent of the angle formed by the slope of the slopes. For clarity, let us consider what is described above, how to calculate the height of a gable roof using the example of a house whose width will be 10 meters . So, for the calculations:
- we take the angle equal to 35 degrees;
- We calculate the tangent, it turns out to be 0.7002;
- 10 meters/2 * 0.7002 = 3.5 meters.
The most used today are hipped structures, and to calculate them you can use the same principle (formula) as for how to calculate the height of the ridge of a gable roof, but only the width of the house is divided not by two, but by four. Plus, when making calculations for a hipped roof, it is important to take into account the length of the ridge run, as well as the rafter system.
calculation of the roof height of a four-pitched structure
The most complex calculations accompany the installation of a mansard-type roof, characteristic feature which can be called the presence of two slopes with a break, which from the outside makes it general form as if “broken”. Arranging a sloping roof will increase the functional area of the attic. Based on the calculation hip roof The example of calculating the height of a gable roof, already discussed above, is based on, but do not forget that the roof has not one angle of inclination, but several. Before moving on to settlement operations, you need to decide on them. Practice shows that it is best to choose the following angle values:
- for the lower one - over 40 degrees;
- for the rest - less than 40 degrees, but definitely more than 15.
To simplify calculations, but at the same time quickly obtain the most accurate result, experts prefer to use the “ golden ratio ", for this, in the drawing the outline of the roof is inscribed in a circle. By resorting to this lucky rule, you can easily solve the question of how to correctly calculate the height of the roof, and most importantly, avoid inaccuracies in the calculation, which in practice will lead to the general appearance of the structure being unaesthetic, inharmonious and simply ugly.
Where to go for help: online resource and consultants
If the roof being erected complex shape, then it requires more voluminous, time-consuming calculations. For calculations, data on the cross-section of the rafters, the pitch between them, and the size of the spans are used truss structure. In addition, the dimensions of roof windows, chimneys, the presence of parapets and overhangs are taken into account; it will be necessary to analyze the possibility of supports and the endurance of the foundation.
Today, anyone who does not know how to calculate the height of a roof can do this by turning to assistants who can be found on the Internet. These could be specialists who are ready to provide you with such services online, or a special Internet resource called a “calculator”, in which case the site visitor enters the requested data and the system performs calculations based on them.
When choosing who to turn to for help, remember that – the design is not cheap, so it does not tolerate errors and inaccuracies. The correctness of the calculations made must be guaranteed. For beginners, calculations for hip, hip and hip roofs turn out to be quite complicated, so it is better to entrust them to a specialist designer with experience in this field. You can only do calculations on your own regarding single-pitch structures for outbuildings and garages, or simple gable structures built to cover a small country house.
Calculations of roof parameters
- This is the most important stage regarding the construction of the roof. It is its result and accuracy that influences how reliable the structure will be, how long it will last, and whether it will have an attractive and harmonious appearance. There is no need to waste time and effort double-checking the results and making sure they are accurate. This is a guarantee that you will have the most durable home, designed for many years of use and providing comfort, coziness and warmth.
Accurate and correctly calculated data will help avoid extra costs for the purchase of materials, and this is reasonable savings during construction.