Calculation of a gable roof: area, height and other parameters. The initial stage of roof construction: roof calculation How to calculate a roof

Construction of any kind is impossible without preliminary calculations, therefore by this preparatory stage should not be neglected under any circumstances. You need to calculate the parameters of the roof itself, its angle of inclination and other aspects, as well as the amount of roofing material that will be required for the surface of the entire roof. We will tell you how to do this in this article.

The calculation of the roof area depends on the type of roof itself. If the roof is simple, i.e. single-slope, then there should not be any special problems in the calculations. But there are other cases when there are certain difficulties in this matter.

Any construction is a rather expensive undertaking, so the owner is glad of any opportunity to save money somehow.

Determining the roof area involves quite a lot of calculations, including finding the height, angle of inclination of the roof, as well as the volume of those building materials that are necessary to build the roof. If everything is done correctly, then you will not have to overpay for building materials by buying more than you need, and you will also save on transporting the material to the construction site.

The complexity of the calculation will directly depend on the type of roof used, of which there are a sufficient number.

How to calculate the roof area of a house: online calculator

How to calculate the square footage of the roof of a house and not make mistakes in the calculations? Our construction calculator will help you with this, which calculates not only the square footage of the house, but also calculates the angle of inclination, the amount of roofing, rafters and much more.

This calculator calculates coverage for gable roof. Before starting the calculations, in the upper right corner of the calculator you need to select roof covering.

Below are calculators for other types of roofs:

Designation of fields in the calculator

Calculation results

The most popular types of roofs

The construction of a roof is a rather complex process in which it is necessary to take into account not only the roofing material, but also hydro- and thermal insulation. You also need to decide on the type of roof. So, Builders distinguish several types of roofing:

If the roof is of a fairly simple shape, without unnecessary kinks, then calculating its area will not be difficult. If the roof is more complex configuration, with many slopes, then you will have to arm yourself with all your knowledge in geometry. This is explained by the fact that we will have to calculate the parameters geometric shapes, included in the conventional roof pattern, and the complexity will lie in the type of these same figures.

In most cases, the roofs of private buildings are as follows: geometric shapes. Square pitched roofs calculated using these formulas:

Trapezoid. Calculation formula (A+B)*H/2.
Rectangle - A*B.
Parallelogram - A*H.
Triangle with equal sides - (A*H)/2.

Shed roof area

Calculating the area of a pitched roof seems to be the simplest, because it does not require a detailed roof plan.

It is calculated using a very simple formula:

S- this is the area of the roof itself (in this case, a rectangle).

A- this is the width of the roof.

B- this is the length.

Let's say the length of a pitched roof is 7 meters and the width is 4. We calculate:

S = 4 * 7 = 28 meters.

How to calculate the area of a gable roof?

This type of roof consists of two pitched roofs With different sides, therefore the calculation will occur according to a similar algorithm. All that remains is to add the resulting values together.

Let us take for the calculation the same parameters as in the previous example, i.e. the width will be 4 meters, and the length will be 7. We make the calculation:

S = (4*7) + (4*7) = 28 + 28 = 56 meters.

Square hipped roof

If you look at such a roof from above, you can see that it consists of four geometric shapes, the areas of which we need to calculate. In other words, we need to calculate these values for two trapezoids and two equilateral triangles. All the resulting indicators will need to be added up.

Let's take the same values as the length and width, i.e. 7 (value A) and 4 (value B) meters, and the height will be equal to the conditional 3 (value H) meters.

We calculate using the following formula:

S = A*H/2 = 7*3/2 = 21/2 = 10.5 meters. The value of the second triangle will be the same, so we add these values: 10.5 + 10.5 = 21 meters.

Calculating the area of a trapezoid:

S = (A+B)*H/2 = (7+4)*3/2 = 11*1.5 = 16.5 meters. We add the value of the second trapezoid: 16.5 + 16.5 = 33 meters.

Add up the resulting values: 21 + 33 = 54 meters. This will be the final area of the hipped surface.

How to calculate the roof area of a complex shape?

In principle, calculating the roof area of a complex configuration is not much different from previous methods. Of course, you will have to spend a little more time, but the calculation rules are common for everyone:

We divide the space into separate geometric elements. As a result, we get various rectangles, triangles, trapezoids and other shapes.
Next, you need to use mathematical formulas familiar from school, thus calculating the area for each figure.
remember, that The length of the slope is taken from the extreme line of the eaves and ending with the ridge of the roof.
We calculate the indicators for all the resulting figures, and then add all these values together.
If you see that the roof slope is of irregular shape, then it is better to break it into two simple shapes, because it is much easier to calculate the area of two trapezoids than the area of a polygon. This way you will save yourself time and nerves.

Calculation of roofs of complex shapes

Dependence of area on type of roofing material

We have already said that calculating the roof area is necessary for in order to calculate the approximate amount of roofing material.

But even if we carried out all the calculations correctly, the material still needs to be purchased with a small reserve so as not to encounter a shortage during the installation process. The type of roofing material also plays an important role, because the technology for covering it can be different.

Slate, metal tiles and corrugated sheets. Each of these materials is sold in the form of sheets, and they need to be laid overlapping. There is such a thing as " effective area» material, so you need to take it into account, and not the actual indicators. If the manufacturing company high level, then it must display such information on the packaging.

The length of the building is divided by the width of the sheet of material. To the resulting value you need to add another 10%, which will be used for pruning. This way we will know the exact number of sheets for the entire width of the roof.
Divide the length of the slope by the length of the sheet of material. Then you need to add 13%, which will be used for overlap when installing sheets.
Then we multiply the number of sheets in the width of the roof and the total number of rows to the eaves. The required figure will be total number sheets of slate or metal tiles for a specific roof.

Calculation of a complex roof

In principle, the calculation of all parameters turns out to be not so complex process if you follow the above recommendations.

Our construction calculator can do all the calculations for you. All you have to do is enter the data on the length, width, height and other indicators of the building, as well as the roofing material used.

Conclusion

Correct calculation of roof parameters is necessary to purchase the required amount of roofing material. If you don't have detailed plan at home, then all measurements will have to be carried out independently, using a tape measure, ladder and other related tools. Also, do not forget that the type of roofing material also plays an important role, so each calculation should be carried out individually.

If you are not confident in your abilities, then you can entrust this matter to professionals who will do all the work for you. It's practically a win-win, only if the price of the issue does not bother you much.

In any other case, you can think a little and make individual calculations. As you can see, this is not so difficult to do, but you can save money, which will then be spent on the same materials and more.

Roofing calculator

Construction of a house requires competent calculation of the estimate. The choice of building material and the process of constructing a building or structure depend on this. You can independently calculate the cost of the roof using a special program.

The amount of material needed and the number of additional elements depend on the geometry of the roof. The more complex the roof, the more basic and Supplies required.

Take measurements and enter data. If the roof structure is complex, then it is divided into separate planes and all distances for cutting the material and geometric construction are measured. When calculating, special attention should be paid not to the roof area, but to the size of each slope.

Ramp width (W), m Ramp length (H), mRamp width (W), m Ramp 1 length (H1), m Ramp 2 length (H2), mWidth of ramp 1 (W1), m Width of ridge (W3), m Length of ramp 1 (H1), mWidth of ramp 1 (W1), mRamp width (W), m Width of eaves overhang (k), m Width of front board (m), m

Each material has its own installation features, different additional elements and fasteners. Therefore, before making calculations, you need to decide directly on the material.

Above the roof layout there are switches for product profiles; they will allow you to select the required profile, taking into account its working width and restricted lengths. To view the layout of sheets on a ramp, select the ramp by clicking on it. Use the arrows to change the length of the sheets according to your needs for the selected slope.

Selected roofing material Price per m², r Metal thickness, mm Covering Color M/h fifth plus GL 0.5 Safari Blue 586 0.5 Safari Blue Soffit T4 without perforation GL Amerika 3.0 white 439 White

Below are the parameters of your roof and the amount of material required, taking into account the prohibited lengths and overlaps of the sheets. You can then add the item to your cart and, if necessary, cancel any items in your cart.

Calculation of roof covering

An easy-to-use roofing calculator will allow you to find out the amount of material required per square meter, the number of additional and component elements. If you find it difficult to complete the calculation, request a call back. Grand Line managers will provide you with detailed technical information about various types roofing coverings, prices, terms of payment, delivery and will create an accurate estimate.

The roof calculation is carried out after necessary measurements. The resulting dimensions must be entered into the appropriate fields of the calculator. When measuring, it is worth considering the following parameters:

roof slope and geometry (single/gable, hipped, mansard, hip);
the presence of hatches and other elements that are left without roofing.

Dimensions of drawings and building plans may differ significantly from actual dimensions. The most accurate calculation will be made only by a highly qualified specialist.

When calculating a complex roof, the roof is divided into separate planes and each element is measured. Special attention pay attention to the size of the slopes.

Before making calculations, you must select a material (corrugated sheeting or metal tiles). Each type of coating has different features installation work, additional elements, fasteners. For roofs with a slight slope, seam roofing is used. Fold is a special seam with which metal sheets connect with each other.

The program allows you to select the thickness of the metal and the color of the coating. Thanks to the wide color scheme you can pick up best option for your home.

Our calculator will allow you to cope with this task online. Soffits are calculated automatically taking into account the material (metal / PVC). Soffits are used to cover eaves and gable overhangs.

If necessary, you can refuse to calculate screws, insulation, additional elements and components. This will reduce the order cost. The calculation is made taking into account the prohibited lengths and overlaps of sheets.

Once payment is complete, add your order to your cart. Delivery of roofing material is possible to any region of the Russian Federation.

When independently designing a three-gable roof and preparing for its installation, you need to calculate a lot in advance important parameters, one of which is the total area of the roof being created. The importance of the exact value of the area is great, since you will have to plan the purchase of not only the selected roofing material, but also waterproofing and windproof membranes, thermal insulation, materials for creating sparse or continuous sheathing.

Calculator for calculating the roof area of a three-gable roof

It would seem that there is nothing complicated, since the roof slopes are ordinary flat geometric figures, the formulas for calculating the areas of which have been known since school. However, the rules can be forgotten, and the features of a complex design with the intersection of planes can confuse an inexperienced novice designer or cause an error. To simplify the calculation process, a calculator for calculating the roof area of a three-gable roof will be helpful.

A number of necessary clarifications will be given below.

Calculator for calculating the roof area of a three-gable roof

What is the basis for calculating the roof area?

The roof of a three-gable roof is a combination of rectangles, triangles and trapezoids.

The total area of the roof is the sum of the areas of the rectangles, triangles and trapezoids that form it.

The slopes of the main building are rectangular, but a triangular section is “cut out” on one of them, bounded by slanted rafter legs. Above an extension, the slopes are usually trapezoidal, but in the case where there is, in fact, no extension, and an additional gable (pediment) is created only to form dormer window, these slopes become triangular.

So, to enter data into the calculator you need to know:

The overall length and width of the main building are easy to measure.
Length and width of the extension. If there is no extension, as such, then the length is indicated “0”, and the width is the width of the created tong (“cuckoo”).

The extension itself may not exist - an additional gable (often called a “cuckoo”) is erected only to expand the useful functionality of the attic space

The lengths of the main rafters of the building and extension. In this case, the elongation of the rafters to create a cornice overhang is also taken into account.

Where can I get the size of the main rafters with the extension for the eaves overhang?

Nothing complicated - if this shelf parameter is unknown, then it can be quickly and accurately calculated. For this purpose, the portal contains calculators, one of which is intended for calculating the length of the main rafter legs, and the second – to determine the necessary lengthening the rafters to form a cornice overhang.

Important - for the main building and for the extension (additional gable), calculations of the length of the rafters are carried out separately, since both the slope angle and the dimensions rafter leg with the same height of the ridge, they may differ.

Prices for corrugated sheets

And finally, it is necessary to indicate the planned width of the eaves and gable overhangs of the roof. This refers to their width in plan, that is, the horizontal distance from the surface of the wall to the edge of the overhang.

The calculator will calculate everything else itself. The exact result will be given in square meters. Well, with the further purchase of roofing and other materials, it is already possible and necessary to lay down a certain reserve - for different types coatings it can vary significantly.

Multi-gable roofs - how is their rafter system designed?

More details about the device multi-gable roof rafter system, the procedure for its calculation and construction can be found in a special publication on our portal, to which the recommended link leads.

How to calculate the roof area depending on its type?

The construction of a roof begins with choosing its type and calculating the required building material. Many people have problems with the latter: either they have purchased less, they have to visit markets or stores again, or they have more - they are left with material that has nowhere to be used. Therefore, calculating the roof area is a mandatory procedure for a thrifty and economical owner. So, let's figure out how to calculate the roof area of a house.

Types of roofs

The most commonly used designs:

single slope;
gable;
hip;
half-hip;
tent.

Roofs are rarely assembled in the form of multi-gable structures, domed or arched. Regarding the shape of the roof, it is necessary to indicate that its elements are geometric shapes. This means that calculating the roof area is the calculation of this parameter of the figures. Now let's move directly to the topic - how to calculate the roof area.

Shed roof

In fact, the shape of this roof is a rectangle. Its area is the product of two sides. Therefore, it is necessary to measure the length of the slope, the width from the facade to back wall, and multiply the resulting indicators among themselves. If a roofing project has been prepared for the house, then these parameters can be taken from it. Or use the suggested online calculator form below.

Gable

This variety roofing structure- two rectangles located at a certain angle to each other.

If the roof is symmetrical, then the calculation of its area is carried out in exactly the same way as in the previous case. Only the end result is doubled.
If asymmetric, then the indicator of each slope is calculated separately, and then the two parameters are summed up.

To calculate the area, simply fill in the fields of the online calculator and the program itself will automatically calculate the area gable roof.

hip

This type of roofing structure consists of four slopes, two of which are trapezoids (identical), two of which are triangles (identical). Moreover, the triangles are isosceles, which simplifies the calculation.

Everyone knows from school geometry courses that the area of a trapezoid is calculated using this formula:

S=(a+b)h/2, where “a” and “b” are the bases of the figure, “h” is the height. The base is the length of the ridge and cornice, the height is the distance from the cornice to the ridge.

Formula for an isosceles triangle:

S=ah/2, where “a” is the base of the triangle, “h” is its height. The base is the length of the cornice, the height is the distance from the cornice to the ridge.

Now, in order to find out the area of the roof of the house (hip), you need to add the results obtained and double them. According to the formula it will look like this:

So=(Str+St)2, where So is the total area of the roof, Str is the area of the trapezoidal slope, St is the area of the hip. And since the slopes on the roof structure are arranged in pairs, their sum increases by “2”.

Or simply use the form below to automatically calculate the hip roof area using an online calculator.

Half-hip

Before calculating the area of a half-hip roof, you need to understand why it is called that. In it, the hip, which is a triangle, is presented in the form of a shortened triangular figure, so the main slope is not trapezoidal in shape. It is complex, so it is recommended to break it down into simpler forms.

Most often, the breakdown is made into a trapezoid and a rectangle. Therefore, for the calculation you will have to use three formulas at once: for a triangle, a trapezoid and a rectangle. The main task of the calculation manufacturer is to accurately carry out the breakdown and correctly measure the parameters of the roofing structure.

There is a variation in half-hip roofs in which the hip is present in the form of a trapezoid. That is, above it there is a triangular pediment, which creates this figure. It turns out that you will have to calculate the area of three figures: two trapezoids with different sizes and a rectangle.

Tent

One of the simple roofing structures, which are four isosceles triangles connected upper corners at one point. Therefore, you will have to calculate only one figure, and then multiply the resulting value by “4”.

Or you can use this formula:

To simplify the process of calculating area hip roof we went ahead and created an online calculator. So you can simply enter your data into the form below and the system will do the calculation itself.

Attic

This variety belongs to the category of broken models. That is, each slope at the place where the racks are installed for the construction of walls has a break line. And more often the angle of the lower part is steeper than the upper. It is along the fracture line that the slope must be divided into two parts, and each one must be counted separately.

In this case, the figures of the lower and upper slopes are rectangles. Their touching sides will be the same, the only differences are in height. Therefore, you can use the generalized formula:

S=(h1+h1)b, where “h1” and “h2” are the heights of the rectangular slopes of the sloping roof, “b” is the length of the slope along the eaves. And since there are two stingrays, a two is added to the formula. Final formula:

Complex roofs

There are not many problems with complex roofing structures. the main task manufacturer of calculations - break them down into simple geometric shapes. And then calculate their areas and add them into one result. There are no other rules.

Automatic area calculation

If you don't want to waste time studying the textbook again high school in mathematics - just enter the parameters of a complex roof required by the online calculator and you will receive an automatic calculation of both the total area of the entire complex roof and its individual parts. The calculator is structured for your convenience. Also, our online calculator can, at your request, calculate the area of the dormer window and chimney; you only need to use the switch suggested in the calculator.

Roof area - depending on roofing material

The variety of roofing coverings does not seem to affect the question posed by the topic of the article, how to calculate the roof area. But it is necessary to understand that the calculation of the roof area is carried out precisely in order to purchase the required amount of coverage for it.

And since there are a huge number of roofing materials on the market, there are also a lot of technologies for their installation. Eg, sheet materials, the sizes of which are divided into general and useful. It is the latter that is taken in order to calculate the required quantity.

Thus, a profiled sheet of grade H20 has a total width of 1150 mm, a useful width of 1100. To calculate the quantity, the second indicator is taken, because the profiled sheets are laid overlapping. This applies to both slate and metal tiles.

In terms of the length of materials used. Corrugated sheeting is sold in lengths up to 12 m. It can be cut so that it covers the slope completely without joints. As for slate and metal tiles, here, as with the width, you will have to take into account the overlap. Therefore, 13–15% is added to the quantity.

The most difficult thing with complex roofs, where the roofing material has to be cut to the required shape. This not only increases waste, but also the complexity of assembly. This especially applies to matching the flooring to the drains.

Conclusion on the topic

In conclusion, it should be noted that the question of how to calculate the roof area does not require the most in-depth knowledge. A school geometry course is enough. The main task is to accurately make measurements that are required to carry out mathematical calculations. Difficulties will be encountered when you have to calculate complex roofing structures. Here you need to correctly break down complex figures and shapes into simpler ones. The main thing is not to lose even the smallest element of the breakdown.

At the same time, we should not forget that the purchased roofing material is a variety of installation technologies, which mainly take into account not general dimensions, but useful.

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Calculating the roof area is a simple geometric task for people involved in construction. However, newbie builders may have some problems doing all the operations correctly. Especially if such calculations are made by a person for the first time. Any small mistake here can lead to the loss of a considerable amount of money. Therefore, in order to answer the question of how to calculate the area of the future roof correctly, it should be understood that the material has more important than the type of roof. The figures obtained by the theory, ultimately, differ somewhat to a lesser extent from the real state of affairs. Accordingly, you should always purchase more material than calculated using the formulas.

In this article

Necessary preliminary preparation

Let's look at what you need to have on hand:

Calculator, formulas. It will significantly free you from unnecessary movements, because you just need to enter ready-made measurements there. You can find such calculators on the Internet.
Roof plan. At least approximate. Needed to know which type will be built. The plan must contain the angle of inclination and the length of the ridge. Based ready plan home, mark the width and length of each slope. When calculating almost every type of roof, you also need to know the height of the entire structure. Often a constant is introduced - a calculated coefficient that depends on the angle of inclination. Here is a list of the most common tilt angles:

9, 14, 18 degrees. – r.k = 1.01 and steps of 0.02
23 degrees – r.k = 1.08
27 degrees – r.k. = 1.12
34 degrees – r.k. = 1.20

The general calculation technology for any type of roof comes down to the fact that complex geometric shapes are divided into simple two-dimensional ones: triangles, parallelograms. To simplify, even all parallelograms are often divided into triangles, rectangles, and trapezoids.

Single-pitch

First, measure the length of the slope (A). To do this, we add to the length of the building (ap, it is also the length larger wall houses) length of overhangs (ac).

The width (B) is calculated according to the school curriculum (ie Pythagoras), do not forget to add the length of the slopes (bс). We use the projection of a triangle, where the legs are the height of the roof (h) and the width of the building (bп, it is also the length of the narrow wall of the house).

B= bc + √(bп 2 + h 2)

In total, the roof area can be easily calculated: S=A*B

Gable

We apply the same formulas as for a single slope, with the exception that ap will be equal to the length of the ridge, and the second leg when calculating the width of the slope will be half the length of the narrow wall (bp).

Roughly speaking, we again calculate the pitched roof. You should remember about overhangs. If you plan to install any window or chimney, then there is no need to take away the space they occupy: it is too easy to make a mistake and, as a result, there may not be enough material.

The area of the roof of the house will be equal to the sum of the areas of the slopes: S = S1 + S2.

Calculation of hip roof area

The elementary form is also called hipped or hipped for a reason: here we will have to again simply sum up the areas of all the slopes. But, if the previous simple figures were rectangles, here we are dealing with four triangles. The most effective option is to use the same school geometric formulas to calculate pairs of triangles. In any case, all triangles will be isosceles. This means that the area of each is calculated using the formula:

St = (m*h)/2, where m is the base and h is the middle line of the triangle.

Or: St = √p*(p-m)*(p-n)*(p-c), where p is the sum of all sides of the triangle (m, n, c), divided by 2:

As a result, we get a calculation of the entire roof area:

S = 2*St1+2*St2

Complex hip, structurally divided into two trapezoids and two triangles. We also calculate the sum of the areas of the triangles. We calculate the trapezoid as follows:

Strape = (m+b)*j/2, where m and b are the lengths of the two bases of the trapezoid, and j is the distance between them. If we imagine j as a line, then it is perpendicular to both sides.

Calculation of areas of complex roofs

Produced in the same way. If the shape formed by the slopes is not a triangle, rectangle or trapezoid, then it is divided on paper into these simple ones. Next, they are calculated based on their geometric properties stated above. For example, parallelograms are usually divided into trapezoids, triangles, and rectangles.

Roof surface

To avoid mistakes, the right decision would be to take more material. For such a popular material as slate, there is even a special calculation formula:

S = (2 x ap + ac) x (2 x bp + bc) x cos(u.n). S is the area of the required coverage, the index “c” is overhangs, “p” is the length of the wall surface, a is the length of the slope, b is the width. This area usually exceeds the “empty” roof area by 12%

Metal tiles are considered more difficult to calculate: we take into account the ridge, valley, and cornices. Often exceeds the “empty” area by 20%. To understand what area you need to collect material for, you need to know its consumption.

The main thing to remember here is: the more complex the roof is, the more expensive the construction.

The roof, along with the foundation and walls, is one of the main structural elements structures, providing protection for the interior of the building from precipitation, waterlogging, temperature changes, wind loads and other influences. At the same time, the roofing system is the most bulky, difficult-to-build structure in the house, since it consists of a huge number of individual components and connections. For most beginning craftsmen, construction turns into full test, which has no end in sight - it is necessary to draw up a project, carry out many calculations, draw diagrams, manufacture elements and, ultimately, assemble everything into a single structure.

Building online calculator roof calculation from the KALK.PRO service allows you to simplify the process of constructing a roof structure at the stage preparatory work, providing a detailed report with the parameters of individual elements and quantity of lumber for their manufacture, providing detailed drawings rafter system and sheathing, as well as visualizing the resulting structure in the form 3D models for subsequent evaluation. In addition, our program takes into account all additional structural elements of the roof, including Mauerlat, vapor barrier, insulation, counter-lattice, OSB sheets. Soon, it is planned to introduce wind and snow load.

The 3D roof designer is simple, convenient and does not require special skills to use - you will need to measure the dimensions of the building, select the type of roof (hard, soft) and indicate the characteristics of the materials used. If invalid values are entered, the program will stop the calculation and indicate the cell where exactly the error was made. Also on the tab of each calculator there is a detailed text instruction with a description of all fields and symbols, which are duplicated in the corresponding images for clarity.

Save time and money by using professional roof calculations on the KALK.PRO website - we have been calculating roofs for more than 5 years and have helped implement over 1000 different projects!

Why are our tools better?

Close cooperation with roof manufacturers

Highest detail in drawings and 3D models

Final report with list necessary materials

Ready-made estimate for the construction of the structure by the contractor

Technical support helps when working with the calculator

Positive feedback and a large number of completed projects

You can calculate the roof on any website and this is a fact, but you should be aware that, unlike other resources, our project has a long history, positive reviews, prompt technical support and regularly updates its work algorithms, eliminating the occurrence of errors. Feedback with users is established and works flawlessly, any visitor can ask a question, and KALK.PRO will try to answer it.

In addition, we would like to highlight the following:

Constructor functionality. Our tools provide ample opportunities for designing a structure - you can customize the characteristics of any element, and if invalid values are entered, the program will stop calculation and will indicate in which field the error was made.
Cooperation with professionals. The KALK.PRO service actively cooperates with manufacturers and designers of roofing systems, so only here you can find such detailed study separate node connections.
Ready estimate. Upon completion of the calculation, the user receives not only a standard report with the parameters of structural elements and a set of drawings, but also detailed estimate with the amount of materials needed for production.
Graphic arts. The main advantage of our service is high-quality detailed graphics, which are as close as possible to the standards of technical documentation. We also provide free interactive 3D model , with which you can evaluate the advantages/disadvantages of the selected design.
. If you experience difficulties using the calculator or have questions regarding the resulting calculation, we will look into the situation and we'll try to answer for any constructive questions 24/7.
Personal Area. Also on our website there is a convenient Personal Area, in which the results of calculating a roof or any other structure are saved - you you'll never lose your project, and you can also download the download at any time, regardless of the time of the operation.

In the comments to each calculator and on the “Reviews” page, you can read the messages real people who use our tools. Check for yourself what users write about us.

Designer capabilities

The KALK.PRO service is a universal assistant for beginners and professional master, with which you can make a truly reliable and safe design. However, it is necessary to understand that the program calculates the roof based on the entered data and does not take into account their correctness, except in exceptional cases when the structure is guaranteed to be unstable. When building a roof (especially for the first time), we recommend paying attention to the following regulations: SNiP 2.01.07-85 (SP 20.13330.2010) “Loads and impacts”, SNiP II-26-76 (SP 17.13330.2017) “Roofs”, TSN 31-308-97 “Roofs. Technical requirements and acceptance rules. Moscow region", SP 31-101-97 "Design and construction of roofs".

We currently provide calculations for the following roofing structures:

roof is pitched;
gable roof (gable, gable);
hip roof;
The roof is hipped (hipped).

Among the main features of the designer, it is necessary to highlight ( - only on KALK.PRO):

Our professional roofing calculators are used by many professionals - if you want to use them for commercial purposes, you can remove our watermark and upload your logo.

Roof calculation result

After entering all the initial parameters, you receive a comprehensive report that contains ready estimate for the manufacture of a structure with detailed calculations of lumber and roofing, a set of drawings of all roof elements in various projections and an adaptive 3D model. The roof area will also be automatically calculated and the angle of inclination of the slope and rafters will be available. Unlike other services, we reveal each element of the structure in detail and do not generalize the parameters so that you can use our results as guidelines for action.

Roof drawings with dimensions

Drawings are an integral element project documentation of any design, since they represent a kind of “working map” for installation work. Many professionals prefer to make a roof plan with their own hands in specialized programs such as AutoCAD, ArchiCAD, etc., however, for a novice master, independent development without proper work experience usually ends before it even begins, or ends very badly. It must be remembered that any accidental mistake can lead to unexpected expenses and disruption of the structure of the entire structure.

Using the online roofing calculator KALK.PRO you eliminate errors in calculations, since the graphics are built based on the actually entered parameters, the correctness of which can be double-checked on an interactive 3D model. Depending on the roof structure we provide different quantities drawings - complex systems are described in more detail. For example, when calculating a bulky hip roof, the kit contains 12 design drawings with detailed description rafter system (in different projections), its elements, sheathing, places of cuts and laying of roofing materials.

When creating the roofing calculator, we made every possible effort to ensure that the subsequent assembly of the structure and the layout of individual elements, in particular, was as fast and comfortable as possible.

3D model

Architectural visualization allows you to visually evaluate the planned structure in real proportions, making sure that the project is completed with high quality and without errors. However, spatial modeling is a painstaking and technically complex process that cannot be performed without special skills, and professional designers Such services cost quite a lot of money.

However, by performing a roof calculation on our website, you receive a FREE adaptive 3D model with precise dimensions, which you can interact with and which can be downloaded in OBJ format, so that you can later load it into your software for editing.

How to calculate a roof using an online calculator?

To calculate the roof using the online calculator, you must correctly fill in all the available fields and click the “Calculate” button. We recommend taking measurements as accurately as possible and double-checking the entered values several times in order to avoid problems in the future when assembling the structure, since you may have to re-manufacture a large number of elements.

Let us remind you that our calculators have built-in functionality to perform:

calculation of the rafter system;
lumber calculation;
calculation of metal tiles;
roof area calculation;
calculation of the roof slope angle.

You don't need to look for other tools on the Internet or bother with manual calculations.

Detailed step-by-step text instructions with graphical annotations for each tool are provided on the corresponding calculator tabs in the Help section. We also suggest watching a short overview video of the calculation gable construction, which demonstrates the main features of the roof calculator.

The area of any classic roof can be calculated using the formulas for the area of a rectangle, triangle, parallelogram, trapezoid: S = a×b, S = (a×h)/2, S = a×h, S = (a+b) × h/ 2, where a, b are the lengths of the sides, h is the height.
The optimal roof angle for constructing a full attic is 45°.
The angle of inclination of the roof directly depends on the climatic conditions of the region: in snowy areas there should be steep roofs, in windy areas - flat ones.
The angle of the roof depends on the roofing material: a rigid roof requires a steeper slope.
The angle of the roof affects the final cost of the structure: a steep roof costs more than a flat one.
The height of the roof is derived from the formula for the height of an isosceles triangle: H = a × sin α, where H is the height directed towards the base, a is the side (the length of the rafter along the slope), α is the angle at the base (applicable for gable roofs).
The optimal value of the eaves overhang of the roof is in the range of 50-100 cm, but not less than the width of the blind area.
The optimal size of the gable roof overhang should be in the range of 40-60 cm.
Roof calculations must be made based on a load of at least 200 kg/m2.
It is recommended to equip the roof with through ventilation holes from the eaves overhang to the ridge.
All fastening materials (especially external ones) must be galvanized or made of stainless steel.
All wood must be treated with fire retardants, antiseptics and antifungal agents.
The wood moisture content for all structural elements should not exceed 18-22%.
It is recommended to use wood of at least class 2, and for load-bearing elements- 1st grade only.
Ideal roofing pie in order from inside to outside: vapor barrier, insulation, waterproofing (membrane), counter-lattice, sheathing, tiles (or other material).

Mauerlat

The optimal size of timber for the Mauerlat is 150x150 mm, sometimes 50x150 mm is used.
It is recommended to fasten the Mauerlat to the armored belt using studs. However, the timber must be insulated so that it does not come into direct contact with the concrete.
The pitch of the studs for attaching the Mauerlat should not exceed 150 cm.

Rafters

The depth of the cut should not exceed 1/3 of the width of the board (optimally 1/4).
The recommended width and thickness of the board for most designs is 150-180 mm and 50-60 mm, respectively. The section of the board is selected depending on the pitch of the rafters and the potential load on the roof.
The distance between the rafters should not be less than 60 cm and more than 120 cm.
It is recommended to fix all connections in two different ways.
To improve reliability bolted connection, it is recommended to use metal plates and corners.
When the span width is more than 10 m, the mandatory installation of additional supporting structures(rails, struts, racks).

Lathing

The recommended board for sheathing is 25x100 mm, in the case of heavy roofs - 40x150 mm.
For hard roofing materials, it is recommended to install dense sparse lathing, for soft ones - with a wider pitch, since OSB sheets will be installed on top.
The pitch of the lathing is selected individually for each material and is specified by the manufacturer. On average, for soft roof- 1-10 cm, ceramic tiles - 30-35 cm, metal tiles - 30-40 cm, corrugated sheets - 30-65 cm.

Insulation and insulation

It is recommended to buy rolled thermal insulation, since slab insulation is difficult to fix (especially alone) and is more likely to crumble.
The recommended thickness of thermal insulation is 15 cm, the minimum is 10 cm.
It is recommended to lay the vapor-waterproofing in an overlap (10-20 cm) with subsequent gluing of the joints.
It is better to lay waterproofing in two layers.
The permissible deflection of waterproofing is no more than 15 mm.

Online roofing calculator from KALK.PRO is the most effective method obtaining design documentation for the manufacture of a reliable roof truss system and other structures.

Construction of any kind is impossible without preliminary calculations, so this preparatory stage should never be neglected. You need to calculate the parameters of the roof itself, its angle of inclination and other aspects, as well as the amount of roofing material that will be required for the surface of the entire roof. We will tell you how to do this in this article.

Any construction is a rather expensive undertaking, so the owner is glad of any opportunity to save money somehow.

The complexity of the calculation will directly depend on the type of roof used, of which there are a sufficient number.

Designation of fields in the calculator

Specify roofing material:

Select a material from the list -- Slate (corrugated asbestos cement sheets): Medium profile (11 kg/m2) Slate (corrugated asbestos cement sheets): Reinforced profile (13 kg/m2) Corrugated cellulose-bitumen sheets (6 kg/m2) Bitumen (soft , flexible) tiles (15 kg/m2) Galvanized sheet (6.5 kg/m2) Sheet steel (8 kg/m2) Ceramic tiles(50 kg/m2) Cement-sand tiles (70 kg/m2) Metal tiles, corrugated sheets (5 kg/m2) Keramoplast (5.5 kg/m2) Seam roofing (6 kg/m2) Polymer-sand tiles (25 kg/m2) m2) Ondulin (Euro slate) (4 kg/m2) Composite tiles (7 kg/m2) Natural slate (40 kg/m2) Specify the weight of 1 square meter of coating (? kg/m2)

kg/m2

Enter the roof parameters (photo above):

Base width A (cm)

Base length D (cm)

Lifting height B (cm)

Length of side overhangs C (cm)

Front and rear overhang length E (cm)

Rafters:

Rafter pitch (cm)

Type of wood for rafters (cm)

Working area of the side rafter (optional) (cm)

Lathing calculation:

Sheathing board width (cm)

Sheathing board thickness (cm)

Distance between sheathing boards
F (cm)

Calculation of snow load (pictured below):

Select your region

1 (80/56 kg/m2) 2 (120/84 kg/m2) 3 (180/126 kg/m2) 4 (240/168 kg/m2) 5 (320/224 kg/m2) 6 (400/280 kg/m2) 7 (480/336 kg/m2) 8 (560/392 kg/m2)

Wind load calculation:

Ia I II III IV V VI VII

Height to the ridge of the building

5 m from 5 m to 10 m from 10 m

Terrain type

Open area Closed area Urban areas

Calculation results

Roof angle: 0 degrees.

The angle of inclination is suitable for this material.

It is advisable to increase the angle of inclination for this material!

It is advisable to reduce the angle of inclination for this material!

Roof surface area: 0 m2.

Approximate weight of roofing material: 0 kg.

Number of rolls of insulating material with 10% overlap (1x15 m): 0 rolls.

Rafters:

Stress on rafter system: 0 kg/m2.

Rafter length: 0 cm

Number of rafters: 0 pcs.

Lathing:

Number of rows of sheathing (for the entire roof): 0 rows.

Uniform distance between sheathing boards: 0 cm

Number of sheathing boards standard length 6 meters: 0 pcs.

Volume of sheathing boards: 0 m3.

Approximate weight of sheathing boards: 0 kg.

Field decoding

The most popular types of roofs

The construction of a roof is a rather complex process in which it is necessary to take into account not only the roofing material, but also. You also need to decide on the type of roof. So, Builders distinguish several types of roofing:

(hip);
multi-slope;

If the roof is of a fairly simple shape, without unnecessary kinks, then calculating its area will not be difficult. If the roof has a more complex configuration, with many slopes, then you will have to arm yourself with all your knowledge of geometry. This is explained by the fact that we will have to calculate the parameters of the geometric shapes included in the conventional roof pattern, and the difficulty will lie in the type of these same shapes.

Types of roofs

In most cases, the roofs of private buildings come in the following geometric shapes. The area of pitched roofs is calculated using these formulas:

Trapezoid. Calculation formula (A+B)*H/2.
Rectangle - A*B.
Parallelogram - A*H.
A triangle with equal sides is (A*H)/2.

NOTE!

It is worth understanding that the more complex the roof, i.e. if it consists of several slopes, the more difficult it is to build, as well as in other aspects - insulation, maintenance, etc. The financial issue has also not been canceled, because such a roof will require more building materials.

Shed roof area

Calculating the area of a pitched roof seems to be the simplest, because it does not require a detailed roof plan.

It is calculated using a very simple formula:

S=A*B, Where

S- this is the area of the roof itself (in this case, a rectangle).

A- this is the width of the roof.

B- this is the length.

Let's say the length of a pitched roof is 7 meters and the width is 4. We calculate:

S = 4 * 7 = 28 meters.

Designations have been changed

How to calculate the area of a gable roof?

This type of roof consists of two pitched roofs on different sides, so the calculation will take place according to a similar algorithm. All that remains is to add the resulting values together.

Let us take for the calculation the same parameters as in the previous example, i.e. the width will be 4 meters, and the length will be 7. We make the calculation:

S = (4*7) + (4*7) = 28 + 28 = 56 meters.

Designations have been changed

Square hipped roof

Let's take the same values as the length and width, i.e. 7 (value A) and 4 (value B) meters, and the height will be equal to the conditional 3 (value H) meters.

We calculate using the following formula:

S = A*H/2 = 7*3/2 = 21/2 = 10.5 meters. The value of the second triangle will be the same, so we add these values: 10.5 + 10.5 = 21 meters.

Calculating the area of a trapezoid:

S = (A+B)*H/2 = (7+4)*3/2 = 11*1.5 = 16.5 meters. We add the value of the second trapezoid: 16.5 + 16.5 = 33 meters.

Add up the resulting values: 21 + 33 = 54 meters. This will be the final area of the hipped surface.

Designations have been changed

How to calculate the roof area of a complex shape?

We divide the space into separate geometric elements. As a result, we get various rectangles, triangles, trapezoids and other shapes.
Next, you need to use mathematical formulas familiar from school, thus calculating the area for each figure.
remember, that The length of the slope is taken from the extreme line of the eaves and ending with the ridge of the roof.
We calculate the indicators for all the resulting figures, and then add all these values together.
If you see that the roof slope is of irregular shape, then it is better to break it into two simple shapes, because it is much easier to calculate the area of two trapezoids than the area of a polygon. This way you will save yourself time and nerves.

CAREFULLY!

In no case do not subtract such roof elements from the resulting area value, like a chimney, ventilation ducts, attic windows, etc. This may result in you simply purchasing less roofing material than required. Be extremely vigilant!

Calculation of roofs of complex shapes

Dependence of area on type of roofing material

We have already said that calculating the roof area is necessary for in order to calculate the approximate amount of roofing material.

Slate, metal tiles and corrugated sheets. Each of these materials is sold in the form of sheets, and they need to be laid overlapping. There is such a thing as the “usable area” of a material, so you need to take it into account, and not the actual indicators. If the manufacturing company is of a high level, then it will necessarily display such information on the packaging.

The length of the building is divided by the width of the sheet of material. To the resulting value you need to add another 10%, which will be used for pruning. This way we will know the exact number of sheets for the entire width of the roof.
Divide the length of the slope by the length of the sheet of material. Then you need to add 13%, which will be used for overlap when installing sheets.
Then we multiply the number of sheets in the width of the roof and the total number of rows to the eaves. The required figure will be the total number of sheets of slate or metal tiles for a particular roof.

Calculation of a complex roof

In principle, calculating all parameters is not such a difficult process if you follow the above recommendations.

Conclusion

Correct calculation of roof parameters is necessary to purchase the required amount of roofing material. If you do not have a detailed house plan, then you will have to carry out all measurements yourself, using a tape measure, a ladder and other related tools. Also, do not forget that the type of roofing material also plays an important role, so each calculation should be carried out individually.

If you are not confident in your abilities, then you can entrust this matter to professionals who will do all the work for you. This is practically a win-win option, only if the price of the issue does not bother you much.

In contact with

The construction of every house does not begin with digging pits or pouring foundations.

Construction begins with project development and calculations.

With a roof, everything happens in a similar way: before starting to install it, a careful calculation of the height, the size of its surface is carried out, the number of structural elements and the amount of material for the roofing cake are determined.

The strength and reliability of the roof, as well as the quantity financial resources, which will be spent on its device.

Surface calculations always start with:

measurements of the main parameters of the roof: angle of inclination, ridge length, length, width and height;
determining the type of roofing material that is planned to be used in the future when constructing the roof.

One of the most important characteristics- This calculated coefficient, used in almost all formulas in calculations.

The value of this coefficient depends on the angle of inclination of the slopes on your house.

For the most popular tilt angles, the coefficient is:

9 degrees - coefficient. 1.01;
14 degrees - coefficient. 1.03;
18 degrees - coefficient. 1.05;
23 degrees - coefficient. 1.08;
27 degrees - coefficient. 1.12;
34 degrees - coefficient. 1.20.

If the shape of the roof is complex, irregular in shape, then during calculations its surface is divided into separate regular shapes, the area for which is calculated in an elementary way.

And at the end, the results obtained are summarized.

Calculation procedure for a pitched roof

This is geometry from a school course.

Houses where they arrange pitched roof, are usually covered with simple materials.

And rectangle is the most common shape.

Therefore, it is enough to measure the length and width of such a rectangle and multiply them.

You should also not forget the coefficient mentioned above.

Calculating a gable roof

Calculations for the surface of a gable roof are more complicated.

And many more factors should be taken into account when making such calculations.

To begin with, we decompose all complex elements, as mentioned, into separate simple shapes: rectangles, squares, triangles.

After all, on the roof, each corner is formed only by the ceiling and the slope.

Therefore, in order to calculate the roof surface, it is necessary to multiply the area of each slope by the cosine of the angle of inclination.

With this calculation, the length of the slope is the distance from the ridge to the eaves line.

Any roof with any number of slopes is calculated in exactly the same way.

You just need to sum up the resulting surfaces of all slopes, multiplied by the cosines of their angles.

If the roof element has a complex irregular shape, then it is also divided into several simple geometric figures and the area of each of them is calculated.

Then all surfaces are summed up.

Let's look at how this is done using the following example: a house has dimensions of 10 x 8 meters.

The rafters are 4.5 meters long.

Naturally, there is an overhang.

The overhang length is standard - 50 cm.

First, let's calculate what surface one slope has:

S = (10 + 0.5 + 0.5) x (4.5 x 0.5) = 55 square meters.

Since the building has two such slopes, the total area will be 55 x 2 = 110 square meters.

Despite the fact that on any roof there are ventilation ducts, chimneys, dormer and attic windows, parapets, they are not subtracted from the resulting area value.

We consider the hipped roof

Then you should determine how difficult each of them is.

The simplest one has a pyramidal shape.

Therefore, when calculating its surface, the formula for a pyramid is used.

If all the slopes have the same dimensions, then it is enough to calculate the area of one of them and then multiply by four.

In the case when it has complex shape, then it is divided into simple figures and the surface of each of them is calculated separately.

Then the results are summed up.

But there is one subtlety: when calculating the area of each slope, it is necessary to take into account the angle of its inclination.

After all, such a roof has different stingrays The angles of inclination may vary significantly.

It should also be remembered that dimensions are taken not along the perimeter of the building, but along the overhangs of the eaves.

Calculating a hip roof

In order for the calculation to be performed correctly, the following must be taken into account:

window size and chimney size;
the length of the slope (between the ridge and the cornice);
parts that are not included in the roofing covering (overhangs, parapets, etc.);
When performing calculations, the junctions of roofing slabs, paving ledges, and standing seams are not taken into account.

Calculating the surface of a hip roof consists of finding the area of two end triangles and two trapezoids.

In any case, if the hip roof has a complex shape, it is divided into several simple figures and calculations are performed separately for each of them.

And then the calculation results for each figure are summed up.

You should know that even though hip roof- this is the best roofing solution, its installation is not cheap.

Calculation for a hip roof

A hip roof is one of the varieties of a hipped roof.

So let's say this is a classic roof with four slopes.

The basis of this design is a quadrangle.

And the slopes are isosceles triangles converging at the central top point.

This type of roof is the most economical, since it has no gables at all.

Since the slope is equal to an isosceles triangle, then:

b is the length of the base of the triangle;

h - height;

S is the area of the triangular slope.

Calculation of a broken attic roof

Area, despite its apparent complexity, is quite simple to calculate.

To do this, you should, first of all, make a roof plan indicating all dimensions.

The entire roof will be a set of simple geometric shapes: triangles, squares, rectangles, trapezoids.

For a square: a x a.

a is the length of the side.

For a rectangle:

In this formula:

a - length,

b is the width of the figure.

For a triangle:

In this formula:

a - the base of the figure,

and h is its height.

For trapezoid:

h x (a + b) / 2.

h - height of the figure,

a and b are the dimensions of the upper and lower bases.

After the area of each of the simple figures into which the broken line is divided is calculated mansard roof, the results obtained are summarized.

Video about construction calculator to calculate the roof.

Sergey Novozhilov - roofing materials expert with 9 years of experience practical work in the field of engineering solutions in construction.

How to calculate the roof area of ​​a house: online calculator

Calculation results

The most popular types of roofs

Shed roof area

How to calculate the area of ​​a gable roof?

Square hipped roof

How to calculate the roof area of ​​a complex shape?

Dependence of area on type of roofing material

Conclusion

Roofing calculator

Calculation of roof covering

Calculator for calculating the roof area of ​​a three-gable roof

What is the basis for calculating the roof area?

Prices for corrugated sheets

How to calculate the roof area depending on its type?

Types of roofs

Shed roof

Gable

hip

Half-hip

Tent

Attic

Complex roofs

Automatic area calculation

Roof area - depending on roofing material

Conclusion on the topic

Necessary preliminary preparation

Single-pitch

Gable

Calculation of hip roof area

Calculation of areas of complex roofs

Roof surface

Why are our tools better?

Designer capabilities

Roof calculation result

Roof drawings with dimensions

3D model

How to calculate a roof using an online calculator?

Mauerlat

Rafters

Lathing

Insulation and insulation

Calculation results

The most popular types of roofs

Shed roof area

How to calculate the area of ​​a gable roof?

Square hipped roof

How to calculate the roof area of ​​a complex shape?

Dependence of area on type of roofing material

Conclusion

Calculation procedure for a pitched roof

Calculating a gable roof

We consider the hipped roof

Calculating a hip roof

Calculation for a hip roof

Calculation of a broken attic roof

Read also

How to calculate the roof area of a house: online calculator

How to calculate the area of a gable roof?

How to calculate the roof area of a complex shape?

Calculator for calculating the roof area of a three-gable roof

How to calculate the area of a gable roof?

How to calculate the roof area of a complex shape?