Calculation of the rafter system of the bone roof calculator. Calculation of the rafting system - we make a roof reliable

Specify the parameters of wooden rafters:

B. - The width of the rafter, the important parameter determining the reliability of the rafter system. The desired cross section of the rafal (in particular width) depends on: loads (permanent - weight of crates and roofing pie, as well as temporary - snow, wind), used material (quality and its type: board, timber, glued bar), the length of the rafter leg, Distances between rafyles. You can determine the approximate section of the timber for the rafted using the table data (width value is a greater value of 3 columns, for example, with a length of rafted to 3000 mm and step 1200 mm, the desired value of the width is 100 mm). When choosing the width of the rafter, be sure to take into account the recommendations entrusted in the joint venture 64.13330.2011 "Wooden structures" and SP 20.13330.2011 "Loads and Impact".

Stropilic Length, mm	Step rafters, mm	The cross section of the rafal
Up to 3000 mm	1200	80x100
Up to 3000 mm	1800	90x100.
Up to 4000 mm	1000	80x160
Up to 4000 mm	1400	80x180
Up to 4000 mm	1800	90x180
Up to 6000 mm	1000	80x200.
Up to 6000 mm	1400	100x200

Y.- The height of the roof, the distance from the skate to the overlap of the attic. Affects the magnitude of the angle of inclination of the roof. If it is planned to arrange a non-residential attic, you should choose a small height (it will take less material for rafters, waterproofing and roof), but sufficient for revision and maintenance (at least 1500 mm). If it is necessary for the equipment of the residential premises under the roof arch, it is necessary to focus on the growth of the highest member of the family, plus 400-500 mm (approximately 1900-2500 mm). In any case, it is also necessary to take into account the requirements of the SP 20.13330.2011 (updated edition of SNiP 2.01.07-85 *). It should be remembered that the roof with a small angle of inclination (small height) can be delayed, which adversely affects its tightness and durability. However, the high roof becomes more vulnerable to the gusts of a strong wind. The optimal angle of inclination is within 30-45 degrees.

X. - Width of the roof (without sinks), is determined by the width of the external perimeter of your home.

C. - The size of the sink, an important structural element of the roof, protecting the wall and the foundation from precipitation, is determined taking into account the climatic conditions of your region (SP 20.13330.2011) and a common architectural idea. For single and two-storey houses without organizing an external water flow of water at least 600 mm. If the drainage system can be reduced to 400 mm (SNB 3.02.04-03). According to the requirements of the IRC-2012, paragraph R802.7.1.1 (international construction code for 1-2 apartment individual residential buildings), the maximum length of the free sink of rafters, which does not require the arrangement of additional support ducts, 610 mm. The optimal sink is considered 500 mm.

Z. - It is the distance from the top edge of the rafter before drank. The size Z. It is associated with the width of rafters with a simple ratio - no more than 2/3 of its width (the neglect of this rule significantly reduces the carrying capacity of the rafyroid). I washed needed for fastening rafters to Mauerlat - a support that perceives the load from the roof and redistributes the bearing walls.

Noting the item "Black and White Drawing" You will get an approximate requirements of the GOST drawing and will be able to print it, not consuming in vain color paint or toner.

Calculation Results:

Length to Sve raftee - This size should be used to mark up the rafted to Mauerlat.

Sveza length It will show how far it is necessary to release the rafter beyond the perimeter of the house to obtain a predetermined roof svel ( FROM) Protecting weather.

Calculated total length of rafters and swells It is not difficult to find out the required amount of sawn timber of the desired length and evaluate how much reagents need to process wood from rotting.

Calculation of angle and section Scroll:the cutting angle is the angle to which the ends of the rafter should be slaughtered to connect each other. Under the same angle, the start of the rafter should be measured by the beginning. To comply with the same corner, it was desirable to use a template on all rafters.

-\u003e calculation of the rafter system

The main element of the roof, perceiving and opposing all types of loads, is Slinge system. Therefore, in order for your roof to reliably oppose all environmental impacts, it is very important to make the correct calculation of the solo system.

For self-calculation of the characteristics of the materials required for the installation of the rafter system, I cite Simplified formulas calculation. Simplifications are made in the direction of increasing the strength of the structure. This will cause some increase in lumber consumption, but on small roofs of individual buildings it will be insignificant. This formulas can be used when calculating two-tie attic and attic, as well as single-sided roofs.

On the basis of the calculation methods below, the programmer Andrei Mutovkin (Andrei-Mutovkin's business card - Mutovkin.rf) has developed a program for calculating the solo system. At my request, he generously allowed to place it on the site. You can download the program.

The calculation technique was prepared on the basis of SNiP 2.01.07-85 "load and impact", taking into account the "change ..." from 2008, as well as on the basis of the formulas given in other sources. I developed this technique many years ago, and time confirmed its correctness.

To calculate the rafting system, first of all, it is necessary to calculate all loads acting on the roof.

I. Loads acting on the roof.

1. Snow loads.

2. Wind load.

On the rapid system, except the above, the load from the elements of the roof is also available:

3. The weight of the roof.

4. The weight of the draft flooring and doom.

5. The weight of the insulation (in the case of a warmed attic).

6. The weight of the solo system itself.

Consider all these loads.

1. Snow loads.

To calculate snow load, we use the formula:

Where,
S - the desired snow load, kg / m²
μ - coefficient depending on the roof slope.
SG - Regulatory Snow Load, kg / m².

μ is a coefficient depending on the roof slope α. Dimensional value.

It is possible to approximately determine the angle of the liner of the roof α as follows the resulting of the height of H on half of the span - l.
The results are reduced to the table:

Then, if α is less than or equal to 30 °, μ \u003d 1;

if α is greater than or equal to 60 °, μ \u003d 0;

if a 30 ° calculate the formula:

μ \u003d 0.033 · (60-α);

SG - Regulatory Snow Load, kg / m².
For Russia, it is accepted on a card 1 of the mandatory application 5 SNiP 2.01.07-85 "Loads and Impact"

For Belarus, the regulatory SG light load is determined
The technical code of the established practice of Eurocode 1. Impact on the design part 1-3. General impacts. Snow loads. TKP EN1991-1-3-2009 (02250).

For example,

Brest (I) - 120 kg / m²,
Grodno (II) - 140 kg / m²,
Minsk (III) - 160 kg / m²,
Vitebsk (IV) - 180 kg / m².

Find the maximum possible snow load on the roof of 2.5 m high and a long span 7m.
The structure is in the der. Babenki Ivanovo region RF.

On the card 1 of the mandatory application 5 SNiP 2.01.07-85 "load and exposure" define SG - regulatory snow load for the city of Ivanovo (IV district):
SG \u003d 240 kg / m²

Determine the angle of the liner of the roof α.
For this, the height of the roof (H) is divided by half of the span (L): 2.5 / 3,5 \u003d 0.714
And on the table we will find the angle of the slope α \u003d 36 °.

Since 30 °, calculation μ We produce according to the formula μ \u003d 0.033 · (60-α).
Substituting the value α \u003d 36 °, we find: μ \u003d 0.033 · (60-36) \u003d 0.79

Then S \u003d SG · μ \u003d 240 · 0.79 \u003d 189kg / m²;

the maximum possible snow load on our roof will be 189kg / m².

2. Wind load.

If the roof is cool (α\u003e 30 °), then due to its sail, the wind presses one of the rods and strives to overturn it.

If the roof is common (α, then the lifting aerodynamic force arising when it is driving with its wind, as well as turbulence under the sips tend to raise this roof.

According to SNiP 2.01.07-85 "Loads and Impact" (in Belarus - Eurocode 1 Exposure on structures Part 1-4. General impact. Wind exposures), the regulatory value of the medium component of the wind load WM at the height Z above the ground surface should be determined by the formula. :

Where,
Wo is the regulatory value of wind pressure.
K is a coefficient that takes into account the change in wind pressure in height.
C is an aerodynamic coefficient.

K is a coefficient that takes into account the change in wind pressure in height. Its values, depending on the height of the building and the nature of the terrain, are reduced to Table 3.

C - aerodynamic coefficient,
which, depending on the configuration of the building and the roof, can take values \u200b\u200bfrom minus 1.8 (the roof rises) to plus 0.8 (the wind presses on the roof). Since our calculation is simplified in the direction of increasing strength, the value C is taken equal to 0.8.

When building the roof, it is necessary to remember that the wind forces seeking to lift or disrupt the roof can reach significant values, and therefore, the bottom of each rapid leg must be carefully attached to the walls or to the matzam.

This is done by any means, for example, with the help of annealed (for softness) with a steel wire with a diameter of 5 - 6mm. With this wire, each rafter foot is screwed to the matsam or to the ears of the slab overlap. It's obvious that than the roof is harder, the better!

Determine the average wind load on the roof of a single-storey house with the height of the skate from the ground - 6m. , an angle of slope α \u003d 36 ° in the village of Babenki Ivanovo region. RF.

3 applications 5 in "SNiP 2.01.07-85" find that Ivanovo region refers to the second wind area Wo \u003d 30 kg / m²

Since all buildings in the village are below 10m., The coefficient K \u003d 1.0

The value of the aerodynamic coefficient C is taken equal to 0.8

the regulatory value of the average component of the wind load WM \u003d 30 · 1.0 · 0.8 \u003d 24kg / m².

For information: If the wind blows into the end of this roof, it acts on its edge (breaking) force to 33.6 kg / m²

3. The weight of the roof.

Different types of roof have the following weight:

1. Slate 10 - 15 kg / m²;
2. Ondulin (Bituminous Slate) 4 - 6 kg / m²;
3. Ceramic tile 35 - 50 kg / m²;
4. Cement-sand tiling 40 - 50 kg / m²;
5. Bituminous tile 8 - 12 kg / m²;
6. Metal tile 4 - 5 kg / m²;
7. Professional flooring 4 - 5 kg / m²;

4. The weight of the draft flooring, the root and the rafter system.

The weight of the black flooring is 18 - 20 kg / m²;
The weight of the lamb 8 is 10 kg / m²;
The weight of the actual stage system 15 is 20 kg / m²;

When calculating the final load on the solo system, all the above loads are summed up.

Now I will open you a little secret. The sellers of certain types of roofing materials as one of the positive properties note their lightness, which, according to their assurances, will lead to a significant savings of sawnwood in the manufacture of a rafter system.

As a refutation of this statement, I will give the following example.

Calculation of the load on the rapid system when using various roofing materials.

Calculate the load on the rafter system when using the heavyweight (cement-sand tile
50 kg / m²) and the easiest (metal tile 5 kg / m²) of the roofing material for our house in the village of Babenka Ivanovo region. RF.

Cement-sand tile:

Wind Loads - 24kg / m²
Roof Weight - 50 kg / m²
Grub weight weight - 20 kg / m²

TOTAL - 303 kg / m²

Metal tile:
Snow Loads - 189kg / m²
Wind Loads - 24kg / m²
Roof Weight - 5 kg / m²
Grub weight weight - 20 kg / m²
The weight of the solo system itself - 20 kg / m²
TOTAL - 258 kg / m²

It is obvious that the existing difference in settlement loads (only about 15%) will not be able to lead to any tangible savings of lumber.

So, with the calculation of the total load q, acting on the square meter of the roof, we figured out!

I especially pay your attention: when calculating, carefully follow the dimension !!!

II. Calculation of the rafter system.

Slinge system It consists of individual rafters (rafter feet), therefore the calculation is reduced to the definition of the load on each rapid leg separately and the calculation of the cross section of a separate rafting leg.

1. Find a distributed load on the pattern meter of each rapid leg.

Where
QR is a distributed load on a rabbown meter of a rafter foot - kg / m,
A - distance between the rafters (step rafter) - m,
Q is the total load acting on the square meter of the roof - kg / m².

2. Determine the working plot of maximum LMAX length in the rafter foot.

3. Calculate the minimum cross section of the material of the rafter.

When choosing a material for rafters, we are guided by the table of standard lumber sizes (GOST 24454-80 lumber of coniferous rocks. Dimensions), which are reduced to Table 4.

Table 4. Nominal size of thickness and width, mm

Board thickness - Section Width (B)	Board width - section height (H)
16	75	100	125	150
19	75	100	125	150	175
22	75	100	125	150	175	200	225
25	75	100	125	150	175	200	225	250	275
32	75	100	125	150	175	200	225	250	275
40	75	100	125	150	175	200	225	250	275
44	75	100	125	150	175	200	225	250	275
50	75	100	125	150	175	200	225	250	275
60	75	100	125	150	175	200	225	250	275
75	75	100	125	150	175	200	225	250	275
100		100	125	150	175	200	225	250	275
125			125	150	175	200	225	250
150				150	175	200	225	250
175					175	200	225	250
200						200	225	250
250								250

A. Calculate the cross section of the rafter foot.

We specify an arbitrarily width of the section in accordance with the standard dimensions, and the height of the section is determined by the formula:

H ≥ 8,6 · LMAX · SQRT (QR / (B · RIPS)) if the slope of the roof α

H ≥ 9.5 · LMAX · SQRT (QR / (B · RIPS)) if the slope of the roof α\u003e 30 °.

H - the height of the section cm,


B - the width of the section cm,
RiPridge - wood resistance to bending, kg / cm².
For pine and fir riesg is equal to:
1 grade - 140 kg / cm²;
2 grade - 130 kg / cm²;
3 grades - 85 kg / cm²;
SQRT - Square root

B. We check whether the magnitude of the deflection is stacked.

The normalized material deflection under load for all roof elements should not exceed L / 200. Where, L is the length of the work area.

This condition is performed with the faithfulness of the following inequality:

3,125 · QR · (LMAX) ³ / (b · h³) ≤ 1

Where,
QR is a distributed load on a rabbown meter of a rafter foot - kg / m,
LMAX is a working plot of a rafter foot of the maximum length m,
B - the width of the section cm,
H - the height of the section cm,

If the inequality is not respected, then increase B or h.

Condition:
Roof angle α \u003d 36 °;
Step rafted a \u003d 0.8 m;
Working plot of the rafter foot of the maximum length LMAX \u003d 2.8 m;
Material - pine 1 grade (Rizg \u003d 140 kg / cm²);
The roof is a cement-sand tile (the weight of the roof is 50 kg / m²).

As it was calculated, the total load acting on the square meter of the roof is q \u003d 303 kg / m².
1. Find a distributed load on the pattern meter of each rafter foot QR \u003d A · Q;
QR \u003d 0.8 · 303 \u003d 242 kg / m;

2. Choose the thickness of the chalkboard for rafters - 5cm.
Calculate the cross section of the rafting leg with the width of the section 5cm.

Then, H ≥ 9,5 · LMAX · SQRT (QR / B · RIPS)Since the bias of the roof α\u003e 30 °:
H ≥ 9.5 · 2.8 · SQRT (242/5 · 140)
H ≥15.6 cm;

From the table of standard sizes of sawn timber, choose a board with the nearest cross section:
width - 5 cm, height - 17.5 cm.

3. We check whether the magnitude of the deflection is stacked. For this should be observed inequality:
3,125 · QR · (LMAX) ³ / b · h³ ≤ 1
Substituting values, we have: 3,125 · 242 · (2.8) ³ / 5 · (17,5) ³ \u003d 0.61
Value 0.61, which means the cross section of the rafted material is chosen correctly.

The cross section of the rafted, installed in increments of 0.8m, for the roof of our house will be: width - 5 cm, height - 17.5 cm.

The online calculator of the bartal roof, also called a two-tie, will help you calculate the desired angle of slopes, determine the cross section and the number of rafters, the volume of materials on the cheek, the consumption of insulating materials, and the existing standards for wind and snow load. You do not have to do extra extra calculations, because in this calculator there are most of the existing roofing materials.

You can easily calculate the flow and weight of such common materials such as bitumen tiles, cement-sand and ceramic tiles, metal tile, bituminous and asbestos-cement slate, Ondulin and others. If you use non-standard material, or you want to get more accurate calculations, you can specify a mass of your own roofing material by selecting the appropriate item in the drop-down list of materials. Calculator makes calculations according to existing Snip "Load and Impact" and TKP 45-5.05-146-2009.

Specify the roofing material:

Choose a material from the list - slate (wavy asbetic sheets): medium profile (11 kg / m2) Slate (wavy asbetic sheets): reinforced profile (13 kg / m2) wavy pulp-bitumen sheets (6 kg / m2) bitumen (soft , flexible) tile (15 kg / m2) from galvanized tin (6.5 kg / m2) sheet steel (8 kg / m2) ceramic tile (50 kg / m2) cement-sand tile (70 kg / m2) metal tile, professional flooring (5 kg / m2) Ceramoplast (5.5 kg / m2) Folding roof (6 kg / m2) Polymer-sand tile (25 kg / m2) Ondulin (erector) (4 kg / m2) Composite tile (7 kg / m2 ) Natural slate (40 kg / m2) Specify the weight of 1 sq. Cover meter (? Kg / m2)

kg / m 2

Enter the roof parameters:

Base width A (cm)

Foundation length D (cm)

Lifting height B (cm)

Length of side skes with (cm)

The length of the front and rear swell E (cm)

Rafters:

Step rafal (cm)

Wood grade for rafters (cm)

Working section of lateral rafters (not necessarily) (cm)

Calculation of doom:

Width of the Grubel Board (cm)

Baseline thickness (cm)

Distance between boards dolets
F (cm)

Results of calculations

Roof inclination angle: 0 degrees.

The angle of inclination is suitable for this material.

The angle of inclination for this material is desirable to increase!

The angle of inclination for this material is desirable to reduce!

Roof surface area: 0 m 2.

Approximate weight of roofing material: 0 kg.

The number of rolls of insulating material with the adoption of 10% (1x15 m): 0 rolls.

Rafters:

Load on the truss system: 0 kg / m 2.

Length rafted: 0 cm.

Number of rafters: 0 pcs.

Obsek:

The number of rows of crates (for the whole roof): 0 rows.

Uniform distance between the shell boards: 0 cm.

Number of clamping boards standard 6 meters long: 0 pcs.

Scope Board Volume: 0 m 3.

Approximate weight of the shell boards: 0 kg.

General information about the duplex

Dux roof (there are options for the name "Double Roof" and "Tweight Roof") - the most common type of roof, in which there are two inclined skate from the skate to the exterior walls of the structure. The popularity of this type of roofs is due to their moderate cost, ease of construction, good operational qualities and an attractive appearance.

In such a design, rafters of different rods are based on each other in pairs and trimmed by the shellboards. The end of the building with a duct roof has a triangular shape and is called a fronton (the name "Plug" is also found. Usually under the rocks of the roof there is an attic room, naturally illuminated with small window holes located at the top of the frontoths.

Additional information on the results of calculations

The angle of inclination of the roof- Under this angle, skate and rafters are tilted to the base of the roof. Roofing materials have individual roof tilt angles, so in some materials an angle may be beyond the limits of permissible norms. Satisfies your angle selected material or not - you will learn in the results of the calculations. In any case, there is always the ability to adjust the height of the roof lifting (B) or the width of the base (A), or choose another roofing material.

Roof surface area - The area of \u200b\u200bthe entire surface of the roof, including soles. To determine the area of \u200b\u200bone skate, it is sufficiently obtained to divide into two.

Approximate weight of roofing material - weight of the chosen roofing material at the rate of the total area of \u200b\u200bthe roof (including soles).

The number of rolls of insulating material - The amount of insulating material required for the roof buildings. The amount in the rolls required for the entire roof area is indicated. The standard of the roll is taken as the basis - 15 meters long, 1 meter wide. When calculating, it is also taken into account 10% in the joints of the joints.

- Maximum weight coming on the rafter system. The wind and snow loads are taken into account, the angle of inclination of the roof, as well as the weight of the whole design.

Length of Stropil - Full length raftered from the ridge of the roof to the edge of the skate.

Number of timelines - The total number of rafters required for the rafter system at a specified step.

Minimum Scroll Scroll / Weight Slinge / Brous Volume

1. The first column shows the cross section of the rafted GOST 24454-80 Softwood sawn timber. Here are the sections that can be used when building a given design. The calculator comes from the total loads that can affect the design of this roof and selects the sections satisfying them.
2. In the second column, the total weight of all rafters with the specified cross section is specified if they are used for the construction of a given roof.
3. The third column indicates the total volume of this bar in cubic meters. This volume is useful to you when calculating the cost.

Number of rows of dohes - The number of rows of the root, which will be needed for the entire roof with the specified parameters. To calculate the number of rows of the crate of one skate, it is necessary to divide the obtained value to two.

Uniform distance between the shell boards - The distance that is recommended to withstand between the dolers boards to optimize the consumption of the material and do without its trimming.

Volume of the shell boards - the total volume of the crate for a given roof. This value will help you calculate the cost of lumber.

Approximate weight of the shell boards - The total weight of the entire crate.

A competently chosen and mounted roof will endure any weather whims and serves more than a dozen years. What will the roof of the country house, and from which materials it will consist, is determined at the design stage. Design technical nuances better entrust professionals. Before making a final choice, the future owner must be obtained about the features of various types of roofs and (importantly) about the amount into which the selected design and the roof material will cost. At this stage, make the calculation of the material on a double-wing roof, or any other, will help the roofing calculator - this is a quick way to get a detailed answer.

Calculator will help assess the cost of the roof in the early stages of planning

Online Calculator Roofing

To learn the approximate cost of the roof, various types, use the following calculator:

Parameters for calculating roofs and roofing material

Before calculating the roof of the house, the calculator will request specific data. One of them is the type of roof. There are two criteria for which you can define the roof type: the angle of inclination of the roof and the number of rods (planes). If the angle of inclination of the roof is zero, the roof is called flat, if more zero - scope. Scope structures, in turn, are divided into species, depending on the number of skates. In private low-rise construction, several varieties of roofs are common, including:

Single car. It looks rather modest, but the simplest constructively and least expensive in construction. It is a plane with a support for bottled walls. Single roof can be seen on the garage, a shed or a modern project in the style of High-tech. Such structures are described by a small number of parameters and are calculated on all online calculators.

Common forms of pitfalls

Double (plug). The most common, classic option with two inclined planes of the rectangular view, connected by a skate, and a centuries-old history. The vertical triangular planes between the skates are called frontons (tongs). In modern private construction Symmetry of the skate - an optional condition. They can have a different bias and differ in size (broken), which opens up great opportunities in the design of roofing structures. The double roof is the perfect option for the attic of the attic. For computing on an online calculator uses such parameters as the length and width of the rods, the length of the soles and the height of the structure.

Walm (four-page). The main skates are called Valmami and have the form of a trapezium, and the frontones are not vertically, and at an angle, turning into the skates. The hip system is much more complicated in the development and installation than the previous ones, but this is compensated by increased structure resistance. In addition, the hollow roof allows you to raise the Ceiling for the attic, making it much more comfortable. The calculator of the hip roof on the online calculator has certain subtleties (the base may be square or rectangular) and turns on the angle of slope.

Multi-type. A complex design consisting of several tongs (double elements). Calculation of such a roof - work for an experienced architect. There are online calculators, which calculate the area of \u200b\u200bthe roof of a three-chip roof, but the result of the calculations they produce very approximate.

The complexity of the rafter system of multi-leveling roofs excludes independent planning

Mansard. Skat consists of two elements: lower, more steep, and upper, color. This design allows you to increase the useful area of \u200b\u200bthe room, but to calculate it on an online calculator, you will need at least a preliminary drawing and understanding of the device of the rafter system.

Types of roofing materials

The question of roofing material is also solved at the design stage. Not only designer preferences are influenced by its choice, but also more real factors, including the amount of precipitation and wind power in the region. An online calculator makes it possible to learn not only the quantity, but also the cost of the selected material. The roof calculator is usually configured to calculate such materials:

Professor.

Metal tile..

Soft (rolled) roof.

Fold coat (steel, aluminum or copper).

Tile. Ceramic (piece), flexible (soft), cement-sand, composite.

Slate (mainly for household buildings).

Calculator calculating metal tile (works with several types of roofs)

Basic elements of roofing design

The roof of a country cottage is not only a decorative detail and a business card of the structure, but also a complex engineering system. It includes a variety of building details, the main of which are the following:

Mauerlat. Bar, which stacked over the bearing walls. It is a support for the rafting system and transfers the load from the roof to the construction.

Rafyla. Brux or boards located at an angle, the basis of the system. Online Calculator Allows you to calculate some parameters of the rafter system.

Auxiliary elements. Racks, beams, runs and tightening serve to fix rafters and strengthen construction.

Konk. The upper rib roof, the place of crossing the skates.

Okeekhet. The lattice design on which the roofing material is attached. For some types of roof, we need solid flooring. The parameters of the crate on the online calculator are calculated quite well, especially for the roof of a simple design.

Basic structural elements of the rafter system

On our site you can find contacts of construction companies that offer the service of designing country houses. Directly to communicate with representatives, you can visiting the exhibition of houses "Low-rise country".

What are counting on an online calculator: species and opportunities

Even having ready-made drawings on the hands, the future owner will not always find time for their careful study and painstaking calculations on paper. Among all the ways to solve the issue of how to calculate the roof of the house, the calculator in the online mode will be the best option. There are two varieties of calculators that perform a certain type of calculations:

Standard calculator for calculating the roof

The most common form allows to obtain the main parameters, from the angle of inclination of the rafted to the permissible load on the roof. In the calculation of roofing material, as a rule, there are all popular options (all kinds of tile, slate, ondulin and other materials). Calculators are widely represented to calculate the same and double and holm roof; There are services for calculating the tent roof or attic. Online calculator of the roof of a duct or single-table is designed for uncomplicated tasks; More advanced calculation programs must be downloaded and installed on your computer.

Fragment of an online calculator calculating a hip roof

Building calculator

For calculations, complex calculation algorithms are used, as a result, not only the digits table can be obtained, but also a set of detailed drawings, as well as 3D visualization. In a construction calculator, as a rule, you can calculate the roof of any type. In addition to the basic parameters, you can find out how many lumber will be required, pick up the optimal insulation and vapor barrier. The drawings will show the layout of the rafter system and the crates and allow you to control the correctness of the angle of inclination and the arrangement of the rafter.

ONLINE Calculator for calculating a bone roof

The calculator for calculating the solo system of the two-tie roof is easy to use by the mechanism that allows you to perform basic design calculations. The interface of any service has a convenient and intuitive look and looks like a set of empty fields with explanation. For the convenience of visitors near the page there are schematic images of various types of roofs with parameters deposited on them.

Before starting computing, you should familiarize yourself with the designation of fields.

The user remains to enter into each field the desired value (size) or select the option from available. When filling, you should pay attention to the dimension - the parameters can be entered into the CM or in mm. After filling the fields, you press the calculation key and get a desired result in the form of the following data:

Number of roofing materials. The calculator will allow calculating the amount of metal tile (or other material) for a rustic house with a double, holm or other roof.

Calculation of the rafting system and the front of the roof. According to the specified width of the wall and height, the service will help determine the length of the rafted and the area of \u200b\u200bthe roof front.

To make the calculation of the material on the roof of the house, the "double" program will require introduce the following values:

Roof dimensions. There are separate fields for entering the height, the width (for each of the sides) and the sink.

Sizes of timing. The width and thickness are set, as well as the distance between the rafters and the distance to the edge of the roof.

Video Description

On the calculation of the roof on the construction calculator in the following video:

Print parameters. Enter width and thickness of boards, the distance between them.

Parameters of roofing material. If the roofing sheet is selected, set the height, width and fastening sheet.

The result of the calculation will be the following parameters:

Roof size. Height and width of the canvas, total area.

Rafyla. The number and length of the rafter. Also calculated the volume of the required material (in cubic meters).

Grussol. The calculation shows the number of rows of boards, the length of each part and the volume of the shell boards.

Cruising material. The area of \u200b\u200bhydro and vaporizolation is calculated. So, if the rubberoid or pergamine is selected as a subcoase material, the calculator shows the required number of rolls (based on the size of the roll), taking into account the adhesion.

Roofing material. The calculator determines not only the area of \u200b\u200bthe coating, but also the weight, and the required amount of the selected material.

Calculator calculating the main elements of the bartal roof

Calculation of additional parameters

Many online services are calculated extra, no less useful quantities:

The angle of inclination of the roof. The calculator will determine not only the optimal value of the angle, but also prompt whether it is suitable for the selected roofing material. By changing the height of the lifting or width of the base, one can achieve complete corner of the material.

Calculation of the Wind and Snow Load. For some areas, such a load can be a determining factor for choosing the type of roof. In the calculator, you will need to enter additional information: the construction region, the type of terrain, the height of the construction of the construction, the variety of wood for rafters.

Calculation of chimney. For safe operation, it is necessary to determine the height of the chimney relative to the rod of the roof. Incorrect design may affect the stable operation of the heating devices and entail unplanned financial spending (if the alteration is required).

When calculating the chimney, the presence of obstacles next to housing

Restrictions on using online calculator

Roofing calculators offered by Internet resources are affordable and very fast way to get the necessary information. But as any mechanisms, calculated on the mass user, such calculators tend to apply generalized calculation techniques. The worst thing is that the process of computing is hidden from a person who has applied to the calculator; Rewrker information at the outlet is very difficult.

Calculator calculating the roof of the house may contain some (permissible) variations of the parameters, which, however, will affect the final result. Among possible results that may contain inaccurate (approximate) values, occurs:

Determination of the total number of roofing material

Building materials never fit into the joint, so the surface area of \u200b\u200bthe roof and the area of \u200b\u200bthe coating will always be different. In calculations, the roofing area is standardly increased by 15% - this ensures the supply when the adhesion is generated.

Video Description

On the calculation of the bartal roof with a free calculator in the following video:

If the roof has a complex design, the calculation is also complicated, since the experienced designer in parallel solves the additional task of minimizing waste. For such purposes, different algorithms are used (with a different accumulating error and with a different result) which one is invested in the calculator, it is known only to its developers.

It is believed that the calculator helps to save on the purchase of building materials. But when installing the roof of a complex shape, in this case, it is often that extra (often notable) materials were acquired. The inverse situation is when the material is not enough and have to pay for unplanned purchase and delivery, not less annoying.

Definition of a downhone

Construction standards prescribe minimal linker indicators for each roofing material. They are calculated taking into account the inclination of the roof and additional indicators (wind and snow load). Specialists perform calculations on the standards of SNiP "Load and Impact" and for additional design standards. What indicators use the roofing calculator in operation, it is not possible to check.

Some calculators take into account additional parameters (the presence of mansard windows and drainage systems)

Calculation of the roof: how to avoid mistakes

In the calculations, you can go one of the following ways:

Calculation of the roof is handed. If there are basic knowledge of geometry, it is possible to make preliminary calculations manually. For this, it is sufficient to stock paper, a pencil, a conventional calculator, and remember that any roof is a set of simplest figures (rectangles and triangles), the calculation of the area of \u200b\u200bwhich is described by the simplest formulas from the school course. The method works badly if the calculations are complicated. They take a lot of time and the risk of error is increasing.

Calculation of the roof spend on the online service. It should be borne in mind that values \u200b\u200bare always averaged; Perhaps for the planned house you will need an individual solution.

Calculator calculator calculating manually. Roofing Online Calculators are a convenient way to simulate the roof design and find out the required number of building materials. Calculation of simple designs to check quite easily, but if you have no profile education, confusion with coefficients and interest is inevitable. Different results cause prolonged recheck and search for errors, as well as distrust of the ability of the calculator (or their own).

Checking the results of the calculation will require time and attentiveness

Professional calculation of the roof. For preliminary calculations in order to determine the materials and construction of the roof, this method is clearly not suitable. But when ordering a turnkey house, the construction company will prepare a full-fledged project in which all calculations will be indicated on the calculations and estimates. In addition, precisely preliminary calculations, specialists can do you at the stage of discussion of the project.

Conclusion

Roofing online calculator is taken to be a good tool to determine the basic parameters of the future roof. But professional builders recommend using it only for an approximate assessment of the number and value of building materials. Also, the calculator can become an indispensable tool for comparing the cost of various technologies.

This article provides a simplified method for calculating the solo system. You will learn how to quickly and correctly decide on the cross section of rafters and the width of the span. Adapted mathematical calculation contains a minimum of formulas and leads to sufficiently accurate results.

There is a standard method for calculating the rafter design, summarized with SNiP 2.01.07-85 "load and exposure". It includes many rather complex counts and reference values. Popular site service - Online Calculation of the rafter system of the bone roof - will allow you to accurately determine the amount of material.

Note. The article discusses the method of calculating the rafter system of the duplex roof with a hollow, semi-wave or fronton without additional structural elements - visors, "birdhouses", towers, etc. and an angle of a row of at least 45 °.

Where to begin

The traditional technique involves the following approach: the design of the roof and the section of the beams is selected. This does not fully meet the requirements of today and the source data in our case will be the following indicators:

1. Requirements (wishes) to roof design. First of all, it is refers to the presence of an attic (residential) floor, the location of the attic windows or the presence of an attic technical room.
2. Existing house sizes or borders of the construction. 70% of private houses are in relatively tight construction, and this is also worth considering when designing a roof. The limited area of \u200b\u200bthe plot and the possible requirements of the neighbors with respect to sunlight can make their own adjustments.
3. Unification. The rafter system is a multi-element design. It is reasonable to try to bring the maximum number of items to one standard - the cross section of the board or timber.

The most difficult, oddly enough, is the first item. However, after a complete idea of \u200b\u200bwhich functions should perform a rafter system (straight or combined), you can start the design stage.

Create a sketch

This stage is one of the decisive, since in it we will learn about the sizes of the elements. The main one - the rafter farm - will be the basis of further calculations. The very drawing is based on two source parameters:

1. Span between carrier walls. It is extremely desirable that the support points of the rafter system, which transmit vertical loads, were located along the axes of the bearing walls or supports. The distance from the projection of the skate to the wall is called semi-trap.
2. Height of the skate from the overlap. This parameter consists of the functional features of the design - the height of the attitude of the attic, an affordable attic or a "deaf" attic space.

As is known, 75% of simple rafter systems are roofs with direct and "broken" skate. This significantly affects the calculations, so we immediately divide these species. Since the basis of any standard roof is a triangular design, we will try to limit ourselves to one formula (Pythagora theorem):

• c 2 \u003d A 2 + B 2

At this stage, it is possible to quite accurately calculate the area of \u200b\u200bthe rods and the flow of roofing material together with the cut. To do this, it is enough to take advantage of the calculation of the slinging system of the bone roof of the online, which is provided by many sites.

Direct equilateral scat

We carry on the sketch of the overlap or the location of the bearing walls (the design does not always imply the presence of wooden overlap) on the scale. Then we celebrate the skate point and carry out straight to the walls taking into account the received roof departure. These direct can already be measured and multiplied by scale - we get the length of the rafter foot.

In accordance with the selected structure of the organization of the internal space (integrated or separated), we have a subcording tightening (beyl) and determine its length. We have in the drawing stops, slopes and vertical racks, observing the requirements that the site portal led in the article "The Slingerous System of the Dusco Roof with your own hands." The spills should not be more than 2 m, and the rafters should necessarily have an intermediate boost. At the same time, it is enough to adhere to the exemplary tolerances.

Applying the formula of the relationship of the parties of the rectangular triangle, you can calculate any of the sizes of the rafter farm. The remaining sizes can be removed from the drawing through the scale. The main task is to get the dimensions of each of the elements.

"Loan" Skat

This type of roof is always taken in connection with the dispute device or the superstructure of the residential floor. It has one characteristic feature - a number of vertical racks at the place of crossing the rods and the substropylene riglel, which can be located both at the level of the top of these racks and under the skate. Rows of racks and riggers form walls and an attic ceiling.

Similarly, we are transferred to the drawing the main elements - first the walls and overlap, then a row of racks and riggers (at the ceiling level), then connect them with lines that will definitely show the shallow shaft form.

After measurements and calculations, the lengths of all elements of the rafter farm should be added and added to the resulting number of 10%. It will be the total length of the design of one farm (CH 1).

Selection of the cross section of rafters and unification

The cross section of the elements of the system, especially the rafter legs, directly depends on the span between the supports in the central part. From all sawn timber for the rafter system, a timber and a board are suitable (not counting factory glued farms). At the same time, the board has a much better indicator of the relationship of the cross section for flexural strength. In our case, we are talking about the reliability of the rafted, for which the board is used, because There is a stock of the sinuses to bookmark the insulation.

Table of dependence of the width of the span and thickness rafters

It is not recommended to arrange rapid farm flaps without intermediate supports.

Council. When splitting two boards to create a vertical support, launch between them in places of attachment of the cutting of the boards of 25 mm ("Bars") with a step of 300-400 mm. So the strength of the support will be higher compared to direct splicing.

After determining a sufficient section of the board, you can calculate the volume of one rafter farm. To do this, multiply the ADC-1 on the cross section area of \u200b\u200bthe board. The resulting volume of one farm (of 1) will be used when calculating the total volume.

Calculation of the step of rafter farms

The step of the attic of the attic rafter system depends on the thickness and construction of the rafter farms.

Table dependency steps from thickness

Dividing the length of the longitudinal (parallel skate) walls on the selected step. We obtain the number of rafting farms (N). Accordingly, we can calculate the length of the farm boards:

• CH 1 x N

farm Board Scope:

• Of 1 x N or ADC 1 x S Single Board X N

Calculation of Maurolat

If the rafter system is arranged on wooden overlap, then the whole horizontal strapping belongs to it. We will look at the option with Mauerlat on a stone wall.

Since the vertical racks, pods and runs are included in the calculation of the farm, we left to calculate the horizontal strapping. There is a simple rule - it should be a thickness of an at least double rafter foot. If the total weight of the roof (along with the cut and roofing material and snow) is significantly high, three layers of the board should be applied.

The volume of the Mauerlat board will be equal to the length of the bearing walls multiplied by the board cross section and on the number of layers. Maurylalat, made of several layers, will better contact the corners.

General counting

We fold all the volumes obtained together and add 20% for waste and trimming. The amount of metal products and fastening elements is determined individually. It is reliably known only to what they are more, the better.

Note. All the above values \u200b\u200band proportions of addiction are taken from regulatory reference.

Despite the seeming simplicity, this adapted calculation can compete exactly with the online calculators of the rafter system. However, the decisive word always remains for those who will execute the project.

Video on the topic

rMNT.ru, Igor Maksimov