Do-it-yourself gable roof rafter system: an overview of hanging and layered type structures. Installing rafters: step by step instructions Roofing and creating an insulating cake

If you decide to build a roof with your own hands, you will need to be especially careful about preparatory phase... You will need to create a project for the roof and roofing pie, make all the calculations and thoroughly study the technological process of future work. We will talk in more detail about all these stages in the article.

Create a roof project for a house

The construction of a roof begins with calculations of the rafter system, as well as the amount of materials required for the roof. The rafter system is made from timber and boards. Its design will be affected by a certain type of roof, that is, it will be one-, two-, four-slope, with straight or broken slopes.

When determining how powerful the rafter system should be, and with what step the rafter legs will be mounted, it is worth taking into account the loads on the roof that it will experience in the future.

The main loads acting on the roof:

weight of the roof frame;
the mass of the nodes of the roofing cake;
wind loads;
the approximate mass of people who will take part in repair or maintenance work;
additional safety factor to resist possible cataclysms.

Wind and snow loads are determined by the climatic conditions of a particular area and the slope of the roof slopes.

When creating the roof of a house with your own hands and determining the amount of material, it is recommended to take into account the dimensions of the roofing sheets, because they will fit with a slight overlap. To minimize waste insulation material, and also to make its installation easier, it is advisable to select the gaps between the rafters, taking into account the width of the strips of the heat-insulating material.

The width of the rigid sheet covering should be equal to the pitch of the rafters, and the width of the insulation material in the form of cotton wool should be approximately 10 mm larger than this value. This will make it possible to lay soft slabs or material in rolls in the spans without leaving gaps.

All calculations for the construction of a roof can be done independently, you just need to use the reference tables. Alternatively, you can use one of the specialized calculators that can be easily taken from the Internet.

When calculating the cost of erecting a roof, another 10% must be added to the entire estimated volume of materials. Consider also consumables, such as all kinds of fasteners, sealants and so on. Transportation of materials will also affect the overall estimate.

Preparation of wooden elements

Do-it-yourself roof construction should be carried out according to a pre-created project, in which all the lengths and cross-sections of the nodes are present, and the technology for their manufacture is also provided.

In order to make the roof of a house from a bar as best as possible, the material used for the frame must be sufficiently dried, not have chips, cracks or other damage. Thus, it is possible to guarantee sufficient reliability of the rafter system, as well as the fact that it will not deform during operation. The roof frame is usually made of coniferous wood because it has greater strength, is less prone to rotting and lasts longer.

To give the frame more fire resistance and to prevent its damage by microorganisms, the elements are coated with fire retardants and antifungal mixtures before installation. Such means are applied twice, making sure that the application of the second layer is started only after the final drying of the first. Before assembling the roof with your own hands, make sure that all the elements have time to dry completely.

Sequence of construction of pitched roofs

Installation of the roof of a house on our own, as a rule, is carried out according to standard projects - these are pitched roofs and simple or sloping roofs gable type. A hipped roof is considered rather difficult to create, since very accurate and complex calculations and extremely accurate markings must be carried out before its construction. In addition, the installation of the diagonal rafters of the hip roof must be performed ideally, because otherwise, the roof will not be able to support high loads during operation. Only professionals are able to carry out all the calculations as accurately as possible and carry out the installation of roofs that are complex in their execution.

To understand how to quickly make a roof, it is worth thoroughly studying the principles of erecting its frame.

By and large, all construction work consists of the following stages:

installation of a Mauerlat;
construction of a rafter system;
installation of a roofing cake.

According to the instructions on how to make a roof with your own hands, you need two or three people with sufficient appropriate work skills.

How to assemble a mauerlat

Even before constructing the roof, the walls must be completely driven out, and waterproofing from roofing felts or roofing material is laid on them. If you plan to install a single or gable roof, then the waterproofing layer under the Mauerlat is laid on two opposite walls on which the legs of the rafters will lie. In the case of a hipped roof, the Mauerlat will be installed on all walls of the building.

Mauerlat is a rectangular or square timber, which is the basis for the entire roof structure. With its help, it is possible to evenly distribute the load on the walls and foundation of the building. The Mauerlat is fastened to the walls on a solid concrete beam, into which steel studs are embedded, or with the help of forged wire laid during the construction of the walls.

The beam is taken based on the complexity of the structure and the total weight of the entire roof. If the installation of the Mauerlat is carried out on all walls, then the connection of all nodes is made by cutting 50 cm across the entire width. And to give better reliability, nails or bolts are used.

Construction of the truss system

Collect the rafter frame begins with the gables of the roof. In those houses where the project provides for internal load-bearing walls or partitions, a beam is laid on them for installing ridge supports. With this scheme, the upper end of the rafters is fixed to the ridge beam, and the lower end is attached to the Mauerlat.

With a small width of the box at home, the skate can be omitted. In this case, the truss will have the shape of the letter "A". The expanding load is compensated by a horizontally installed transom, which also adds strength to the frame. The junction of the upper sections of the rafters must be reinforced with metal or wooden linings.

When constructing a roof without overhangs, the lower end of the rafters is cut off and abuts against the Mauerlat. And if the owners want to make overhangs, then for laying the rafter leg they make a recess on it, which will lie on the Mauerlat with a horizontal cut.

This method of installing the rafter system is allowed when the Mauerlat is not used. In this case, beams are laid across the long walls with a step equal to the distance between the rafter legs. In length, they should slightly exceed the width of the structure. For reliability, such a bar is fixed either with wire or with reinforcement pins embedded in the wall. At the request of the owner of the house, in the lower part, the rafter legs are laid with or without overhangs.

When it comes to a roof for an attic, as a rule, they equip a layered type of rafter frame. That is, additional support pillars are mounted under the rafters, connecting them with girders. Braces and other frame details provide it with rigidity and reliability.

Making a roofing roof pie

They begin to build a roofing pie at the end of the installation of the rafter system. First, it is advisable to lay a layer of water-repellent material - it can be either a membrane or roofing material. It is fixed to the rafters, while it is strongly recommended not to cover the ridge with a layer of moisture insulation, as this will negatively affect the ventilation of the roof. On top of the waterproofing layer, 50 mm bars are nailed - they will serve as a counter-lattice. This creates the required air gap between the material and the waterproofing layer.

The lathing, which is fixed to the counter-lattice, can be made of boards, bars or wood-based materials in the form of slabs.

For roofs with slopes, as a rule, the following are used as roofing:

sheet metal materials (metal tiles, flanged roofing or corrugated board), asbestos cement (slate), ondulin;
ceramic materials, slate, shingles.

DIY thermal insulation installation

The pitched roof is insulated from the inside. For this, materials based on plant fibers (hemp, seaweed, straw mats) and ecowool are used. The most common is mineral wool, as the most environmentally friendly and refractory material, extracted from basalt or glass. Spray-applied polymer sheets are not often used. The disadvantages of the latter materials include: high cost, complexity of installation, as well as the need to use specialized devices.

According to the technology, the erection of the roof must be accompanied by the laying of a vapor barrier in the form of a special membrane. Thus, it is possible to protect the insulation and rafters from wood from rapid destruction due to exposure to dampness. The use of plastic film and other materials instead of the membrane is strongly discouraged.

Stick to the entire roofing technology, and in the end you will get the perfect structure that will serve you for more than a dozen years!

More and more people are striving to make their cherished dream come true - to get out of the multi-storey urban development into own house... Acquired suburban area quickly turns into a construction site. And, in accordance with the natural mentality of most Russian men, work on the construction of a new home is very often carried out on their own. Moreover, many of the amateur craftsmen do not have much experience in this area at all, they learn literally on the go, look for useful and reliable information in available sources, including on the pages internet resourcesdedicated to construction. We hope that our portal will provide them with serious assistance in this matter.

So, after the walls of the house have been raised on a reliable foundation, it is necessary, without delaying with this, to proceed to creating a roof and laying a roofing covering. There can be many options here. And one of the most commonly used is the gable roof structure. It is not as difficult in calculations and installation as some others, that is, even a novice builder should cope with it. Therefore, the topic of this publication is the construction of the roof of a private house with your own hands using the example of a gable rafter system with

It should be noted right away that the article does not provide a ready-made "recipe". The aim is to demonstrate the principles of calculating a gable roof and the sequence of its construction. And a master who has the appropriate estimate must already bring the recommendations received to his own, specific construction conditions.

General information about the construction of gable roofs

The basic principle of the construction of a gable roof is probably already clear from its name. The roof of such a roof forms two planes, converging along the ridge line, and resting on the long walls of the house (along the cornice lines). From the end sides, the roof is limited by vertical gable walls. As a rule, both along the line of the cornices and along the pediment, the roofing is slightly released outside, outside the building in the plan, so that overhangs are formed that protect the walls from direct rainfall.

Most often, the slopes are symmetrical. Sometimes they resort to asymmetry, when the slopes are located at different angles to the horizon and, accordingly, differ in their length. But these are isolated cases, and will not be considered within the scope of this publication.

The height of the roof in the ridge, that is, the steepness of the slopes, can be different - it all depends on the planned use of the attic space, the architectural idea of \u200b\u200bthe owners, the type of roofing used.

Gable roofs have proven their high reliability ... And the relative simplicity of the design makes them so popular among private developers.

The external similarity of gable roofs does not mean the uniformity of their design. roof systems... It is precisely in this issue that there can be significant differences, depending both on the size of the building and on its design features.

By the principle of structure, gable roof truss systems can be divided into two groups:

If the rafters rest on the outer walls of the building and are interconnected in a ridge knot, then such a system is called a hanging system.

To give additional rigidity to this design, the rafter legs of each pair are reinforced with horizontal puffs (contractions). Vertical struts supported on floor beams or diagonally installed struts can also be used.

In the case when the structure of the house assumes the presence of a main wall inside the building, a layered rafter system is often used. The name speaks for itself - the legs "lean" on the racks, which, in turn, rest on the bed, laid along top end of capital inner walls. Moreover, this wall can be located both in the center and offset from it. and for large buildings, two internal walls can also be used as supports. Several examples of layered systems are shown in the illustration below.

However, a kind of "hybrid" of both systems is often used. The rafters in these cases, even without the presence of an internal partition, also receive support on the central post in the ridge assembly, which, in turn, rests on powerful floor beams or on horizontal puffs between the rafter legs.

In any of the systems, especially in cases where the rafter legs are of considerable length, additional reinforcement elements are used. This is necessary to exclude the likelihood of deflection of the beam or even its fracture under the action of loads. And the loads will be tested here. First of all, it is static, due to the weight of the rafter system itself, lathing, roofing and its insulation, if it is provided for by the project. Plus, there are large variable loads, among which wind and snow loads come out on top. Therefore, they strive to provide the required number of support points for the rafter legs in order to prevent possible deformation.

Some of their reinforcement elements are shown on the rafter system design diagrams:

The illustration above shows an example of a layered rafter system:

1 - Mauerlat. Usually it is a bar rigidly fixed to the upper end of the outer walls of the building. It serves as a support and base for securing the lower part of the rafter legs.

2 - Lezhen. A bar fixed on the inner partition of the building.

3 - Rack (another name - grandmother). Vertical support going from the bed to the ridge girder.

4 - Ridge run. A bar or board that connects the center posts and serves as the basis for securing the upper ends of the rafter legs.

5 - Rafter legs.

6 - Braces. These are additional reinforcement elements by means of which it is possible to reduce the free span of the rafter leg, that is, to create additional support points for it.

7 - Battens to match the selected roofing.

Prices for fastenings for rafters

rafters

In systems of a hanging type, reinforcement is performed by installing horizontal puffs (item 7), which rigidly bind the opposite rafter legs, and thereby reduce the bursting load acting on the walls of the building. There may be several such puffs. For example, one is installed in the lower part, closer to the level of the Mauerlat, or even almost flush with it. And the second is closer to the ridge knot (it is often also called the crossbar).

With a long rafter length, it may also be necessary to use vertical struts (pos. 3) or diagonal struts (pos. 6), and often both of these elements in combination. They can be supported by floor beams (item 9), as shown in the illustration.

It should be correctly understood that the shown schemes are not at all a dogma. There are other designs of truss systems. For example, the fastening of the lower part of the rafter legs is often applied not to the Mauerlat, but to the floor beams taken out beyond the walls of the house. Thus, the required

In the roofs of large houses, more complex schemes can be used. For example, the rafters are connected by additional longitudinal girders, which, in turn, are supported by vertical posts or struts. But taking on the creation of such complex systems without well-established experience in this area is hardly reasonable. Therefore, we will restrict ourselves to considering the construction of gable roofs, which are quite simple in design.

Calculating the parameters of a gable roof

The construction of the rafter system and the arrangement of the roof on its basis should always begin with the necessary calculations. What tasks are being set?

First of all, it is necessary to understand the relationship between the height of the ridge and the steepness of the roof slopes.
After that, it will be possible to accurately calculate the length of the rafter legs, both "clean" and full, that is, taking into account the planned eaves.
The length of the rafters and the estimated pitch from the installation will make it possible to determine the cross-section of the material suitable for their manufacture, taking into account the expected loads on the roof. Or, conversely, based on the available material, choose optimal step and to place additional support points - by installing reinforcement elements, which were mentioned above.

The listed parameters will allow you to draw up a diagram and a drawing of the rafter system as accurately as possible, and correctly arrange all its elements. According to the existing scheme, it will be much easier to calculate how much and what material will be required for installation.

You will need to know the total area of \u200b\u200bthe roof slopes. It is necessary for the purchase of roofing material, hydro and vapor barrier membranes, insulation, if thermal insulation of the roof is planned. In addition, the area parameter is also important for determining the amount of material for arranging the battens for the selected roof covering.

To make it clearer in the course of the presentation of the calculation procedure, the main quantities are schematically shown in the illustration below:

D - the width of the house (the size of its gable wall);

VC - the height of the roof in the ridge above the plane of the Mauerlat or floor beams, depending on what the lower ends of the rafter legs will be attached to;

and - the angle of steepness of the roof slopes;

FROM - the working length of the rafter leg, from the ridge to the Mauerlat;

ΔC - lengthening the rafter leg to form the planned eaves;

Sh - the step of installing the rafter legs.

Let's start examining the above issues in order.

The ratio of the steepness of the slopes and the height of the roof ridge

These two quantities are closely related. AND totheir calculation can be approached from various angles, taking certain criteria as the starting point.

For example, the owners see their house with a high roof, somewhat vaguely reminiscent of the Gothic style of architecture. It is clear that with this approach, the height of the roof in the ridge and, accordingly, the steepness of the slopes increases sharply. However, it should not be forgotten that such roofs experience maximum wind loads due to their pronounced "windage". But the snow on such slopes will practically not linger. So it's worth considering these two factors initially. Perhaps for an area closed from the winds, but with the predominance of snowy winters, this option will generally be the most acceptable.

There are pronounced steep slopes and a high ridge - snow on such a roof does not linger at all, but the effect of the wind becomes maximum

But do not forget that the longer the rafter legs, the more difficult the system itself will be in the arrangement, which will require a lot of reinforcing details.

Another consideration to make the roof higher is very often the desire to have a functional attic space, up to the equipment of a full-fledged living room in it.

For an attic room, a broken rafter system is certainly preferable. But if, nevertheless, a gable is planned, then a lot of space is eaten up by the corner zones along the line of connection of the rafters with the Mauerlat. We have to increase the steepness of the slopes (see above).

True, there may be an acceptable solution here. For example, the Mauerlat is not located at the floor level, as in the "classic" version, but on the side walls, which are deliberately raised above the floor to a certain height. Then, even with a large steepness of the slopes, and without much complicating the design of the system, magnon will achieve very spacious attic rooms.

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metal tile

By the way, it is this option that will be considered below when the story will go already about the installation of the rafter system.

It happens that the owners of the future house, on the contrary, decide on the minimum steepness angles of the roof. This can be caused by structures that save materials, the lack of the need for usable space in the attic, the peculiarities of local conditions - for example, very windy, but not particularly snowy terrain.

True, with this approach, one must not forget that any roofing has certain lower boundaries of the steepness of the slopes. For example, if you plan to lay piece shingles, then it is necessary to provide an angle of steepness of at least 20, and for some models even 30 degrees. So if the plans already have this or that roof covering, its characteristics should be correlated with the height and steepness of the roof.

So, how is the calculation done. As a constant value - a constant, we have the width of the house along the pediment wall ( D). Using the well-known trigonometric formula, it is easy to find the height ( VC), starting from the planned steepness of the slopes (angle and).

Sun \u003d 0.5 × D × tg a

It is clear that to calculate a symmetrical gable roof, half the width of the building is taken, that is 0.5 × D.

One more nuance. When calculating according to this ratio, the height difference is taken to be the height difference between the ridge point and the Mauerlat plane. That is, the excess over the attic floor is not always meant - this should be borne in mind.

This formula is included in the proposed calculator.

Calculator of the ratio of the steepness of the slopes of a gable roof and the height of its ridge

Specify the requested values \u200b\u200band click "Calculate the height of the ridge Vk"

Planned roof slope a, (degrees)

It is not difficult to perform reverse calculations with this calculator. For example, the owners are interested in the height of the ridge to have a specific value. This means that changing the angle value on the slider sequentially and, in just a few seconds it is possible to determine at what steepness this condition will be met.

What is the length of the rafter legs?

Having on hand the results of the previous calculation, it is not difficult to determine what the "net" length of each of the rafter legs will be. The term "net" length in this context means the distance from the point of the ridge to the Mauerlat.

Here the Pythagorean theorem will come to our rescue, which accurately describes the relationship between the sides of a right-angled triangle. We know two legs - this is half the width of the house ( 0.5 × L) and ridge height ( VC). It remains to find the hypotenuse FROM, which is just the length of the rafter leg.

C \u003d √ (Bk² + (0.5 × D) ²)

We calculate manually or use an online calculator, which will be much faster and more accurate

Calculator for calculating the "net" length of the rafter leg of a gable roof

Enter the requested values \u200b\u200band click the "Calculate the length of the rafter leg"

Ridge height above the Mauerlat plane Vk, meters

House width along the pediment wall D, meters

That's not all.

It was already mentioned above that to form the eaves overhang of the roof, the rafters are often made somewhat longer. How to take into account this "addition" to the "net" length of the rafter leg?

Again trigonometry comes to the rescue. Everything turns out quite simple:

ΔC \u003d K /cos a

The same approach is practiced if the eaves overhang will be formed by building rafters by filly.

The working length of the filly is calculated in the same way. This refers to the release of the filly outside, without a section of its connection with the rafter leg.

In order not to force the reader to search for the values \u200b\u200bof trigonometric functions, a calculator is placed below:

Calculator for calculating the elongation of the rafter leg to create the eaves overhang of the roof

Specify the requested data and click the button "Calculate rafter elongation (working length of the filly)"

The planned width of the eaves K, meters

The magnitude of the slope steepness a, degrees

Now it remains only to sum up the "net" length of the rafter leg and its lengthening by the overhang - this is easy to do even in your mind.

The resulting value will become a guideline when purchasing the necessary lumber and cutting blanks. It is clear that during installation, the rafters are not cut immediately to the exact size - it is easier after installation to trim the ends protruding on the overhangs to the required length. Therefore, either the board is usually taken longer by about 200 ÷ 300 mm.

By the way, the option is not excluded that the resulting total length of the rafters will exceed the standard dimensions of lumber that can be purchased locally. This means that you will have to build up the rafters - you must also be prepared for this in advance.

Calculation of loads falling on the roof, selection of the optimal section and placement of rafters

This stage of preliminary calculations can be considered the most important and difficult. It is necessary to determine what loads the roof structure will have to cope with. This, in turn, will allow you to choose the right cross-section of lumber for the rafter legs, find the optimal step for their installation, find out whether reinforcement elements will be needed in order to reduce the free spans of the rafters by installing additional support points.

The total load on the rafter system, as mentioned above, is made up of several values. Let's deal with them one by one.

Static weight loads are the mass of the rafter system itself, the laid roofing with the corresponding crate, and if the roof is insulated, then also the weight of the thermal insulation material. Different roofs have their own average values \u200b\u200bof this load, expressed in kilograms per square meter... It is clear that the specific gravity, for example, of a roof covered with ondulin, cannot be compared with natural ceramic roofing shingles.

Such indicators are easy to find on the Internet. But below will be offered an online calculator, which has already taken into account all these averages. In addition, a certain margin of safety is already included in this indicator. Such a stock is necessary, for example, to move a person on the roof performing certain repair work or cleaning the slopes.

But the static pressure of snow deposits is just the next factor of external influence on the roof structure. And you can't ignore it. In many regions of our country, due to their climatic characteristics, this criterion for assessing strength becomes almost decisive.

Snow protectors prices

snow holders

- Climatic features of the region. IN as a result of long-term meteorological observations, specialists have developed zoning of the country's territory according to the average level of winter precipitation. And, accordingly, according to the load rendered by snow masses on building structures. A map of such zoning is shown below:

Quantitative load indicators for zones on the map are not shown. But they have already been included in the calculator's calculation program - it will be enough just to indicate the zone number for your region of residence.

- The second factor that directly affects the level of snow load is the steepness of the roof slopes. First, as the angle increases, the force application vector also changes. And secondly, on steep slopes, the snow lingers less, and at steep angles from 60 degrees and above there is no snow drift on the roof in principle.

It will be a little more difficult with wind impact, since more initial criteria are taken into account. But you can figure it out too. The calculation algorithm is somewhat simplified, but gives a result with a sufficient level of accuracy.

First of all, by analogy with the snow load, according to a special map-scheme, it is necessary to determine your zone by the level of wind pressure. The map is presented below:

The average wind pressure indicators for each of the zones are entered into the calculator's calculation program.

But that is not all. The level of wind impact on a particular roof depends on a number of other criteria:

- Again the steepness of the slopes is taken into account. This is easy to explain - both the moment of application of the force and the area of \u200b\u200bthe wind effect change, since with steep slopes their windage increases, and with too shallow slopes, the action is not excluded counter-directional, lifting force.

- The overall height of the house at the level of the ridge is important - the higher it is, the more significant the wind loads will be.

- Any building is characterized by the presence of natural or artificial wind barriers around it. So, it is practiced to subdivide such conditions for the location of the building into three zones. Their evaluation criteria are entered in the corresponding field of the calculator, and it will not be difficult to select the desired option.

But when choosing this parameter, one more nuance must be taken into account. It is believed that such natural or artificial obstacles really affect the level of wind pressure only if they are located at a distance not exceeding thirtyfold the height of the house. For example, for a building 6 meters high, a forest, located, say, 150 meters from it, yes, will be a natural obstacle to the wind. But if the edge is more than 180 meters from the house, the area is already considered open to all winds.

All static and dynamic loads are summed up, and the final value becomes decisive for the selection of material for rafter legs. However, if you operate with the parameter of specific pressure per area, it will not be very convenient. It is better to bring this value to the distributed load on the rafter legs.

Let us explain: the smaller the installation step of the rafter pairs, the lower the distributed load falls on each running meter of the rafter itself. And according to this distributed load, the choice of the optimal section of the bar or board, going to the manufacture of rafters, will take place.

All of the above factors affecting the level of the load falling on the rafters are included in the calculator's calculation program. That is, the user just needs to specify the requested values \u200b\u200bin the appropriate fields, and get the finished result of the distributed load, that is, per linear meter of the rafter beam (board). By changing the value of the step for installing the rafter pairs, you can observe how the result will change and choose the optimal arrangement. And we need the resulting final value just below.

Calculator for calculating the distributed load on the rafter legs

Green lines.

Let's say, after calculations using the proposed calculator, the distributed total load is 70 kg / r. meter. The closest value in the table is 75 (of course, rounding is carried out upward to provide a margin). In this column, we find the indicator of the free span of the rafter legs, that is, the maximum distance between the support points. Let it be 5 meters in our case. This means that from the left side of the table you can write out all the values \u200b\u200bof the sections of a bar or board that are guaranteed to withstand such a load without the risk of deformation or fracture. By the way, the values \u200b\u200bfor the diameter of the log are also shown, if the rafters are prepared from round timber.

It is clear that there is room for choosing the best option. In addition to the already mentioned change in the pitch of the rafter legs, which, as we recall, leads to a change in the distributed load, you can try, while still on the diagram, to additionally place elements of the system's reinforcement, racks or struts in order to reduce the free span. It also makes it possible to use smaller sawn timber.

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ceramic tiles

Calculating the area of \u200b\u200ba gable roof

We will probably not dwell on this issue in detail. Easier taskthan to determine the total area of \u200b\u200btwo symmetrical rectangles, it is difficult to imagine.

The only caveat. When payment the area of \u200b\u200bthe slope, do not forget that the length of the slope from the ridge to the cornice is taking into account the cornice overhang. And the length along the cornice line - taking into account the gable overhangs on both sides of the house. And the rest - everything is simple, the usual multiplication of these spirit values \u200b\u200bamong themselves.

How much material is required for the roof sheathing?

We figured out the size, number and location of the rafter legs and reinforcement elements of the system. They put it on a schematic drawing, and it will not be difficult to calculate the required amount of materials. But a large amount of boards or timber will also be required for the lathing under the roofing. How to calculate?

This question primarily depends on the type of roofing planned for the flooring. Secondly, in many cases, especially when using sheet roofing materials, the steepness of the slopes is also important. But since the flooring of a metal tile will be shown as an example in this article, the calculation of the lathing will be done specifically for it.

This is exactly the coating for which there is no point in making a continuous flooring, and the step of installing the lathing guides will not depend in any way on the angle of the roof slope. It is only important that each of the longitudinal (in the direction along the line of the cornice) rows of "tiled" modules rests with its downward-looking "step" on the lathing crossbar, where the fastening is performed with the help of roofing screws.

Thus, the spacing of the lathing guides depends only on the model of the metal tile itself, that is, on the length of its modules.

In addition, it is recommended to reinforce the sheathing with an additional board at the start and finish sections (along the lines of the cornices and the ridge), as well as, necessarily in order, along the valleys on both sides, if they are present in the roof structure.

For the lathing, boards with a thickness of 25 mm are used if the installation pitch of the rafter pairs does not exceed 600 mm. With a greater distance between adjacent rafters, but not exceeding 800 mm, it will be safer to use a 32 mm thick board. If the step is even greater, then preference should be given to a beam with a thickness of 50 mm, since at such significant distances it is impossible to allow the guides to bend under an external weight and dynamic load.

The calculator below will help you quickly and accurately determine the amount of lumber you need to batten. Moreover, the result will be shown in volume terms, in the total linear length of the selected board or timber, and in the number of standard 6-meter boards (bars).

According to statistics, every second homeowner built his own home. According to their reviews, self-erecting a roof is one of the most difficult stages for non-professional builders. Therefore, it is very important to approach this stage with a complete understanding of all the nuances of the process. To figure out how to make a roof with your own hands, you need to study the device, installation technology, the procedure for work and the features of fastening all components of the structure.

Roof types

First you need to decide on the form. Today the most popular types are:

Form features

Overlapping the roof with one single slope will save nerves and materials, since structurally this is the simplest option. If you make such a frame yourself, then the labor intensity of the work will be the least, and the installation speed is high. But this form has a drawback - there is no possibility of arranging a full-fledged attic or attic, since the under-roof space is too low.

A gable roof is installed much more often. It is a little more difficult to manufacture, but allows more space. Compared to the hipped one, it has less complexity and weight, however, you will need to make triangular pediments at the ends of the building.

Gable - the most popular form

Before you start building a roof with four slopes yourself, you need to seriously prepare. This system has more elements than the previous two. In addition, there is no way to make full-fledged windows in the attic, since the roof structure is devoid of gables and installation is difficult or unavoidable.

The four-slope is complex in the device, but the savings are achieved due to the lack of gables

For the attic, a combined design with. In this case, the lower part of the roof has a greater slope than the upper part. Such an assembly allows you to raise the ceiling in the room and make the built house more comfortable.

The broken line is not the most "architectural", but very effective in terms of the used space

Payment

Before starting work, you need to make a design calculation. It makes no sense to calculate the cross sections of all elements. In most cases, they can be taken constructively:

mauerlat - 150x150 mm;
racks - 100x150 or 100x100 mm, depending on the section of the rafters;
struts - 100x150 or 50x150 mm, taking into account the convenience of connecting to the rafters;
tightening - 50x150 mm on both sides;
purlins - 100x150 or 150x50 mm;
overlays with a thickness of 32 to 50 mm.

The calculation is usually performed only for rafter and slant legs. It is required to choose the height and width of the section. The parameters depend on:

roofing material;
snow region;
step of the rafters (selected so that it is convenient to lay the insulation, for mineral wool 58 cm should remain between the elements);
span.

You can choose the cross-section of the rafters using general recommendations. But in this case, it is recommended to make a small margin.

The calculation is usually performed for rafter legs

If you do not want to understand the intricacies of the calculations, you can use special ones.

If you intend to make a warm roof, then the height of the section of the legs is selected taking into account the thickness of the insulation. It must be mounted so that it does not protrude above the supporting beams. You also need to take into account that for mineral wool, a ventilation gap of 2-4 cm is made between it and the coating. If the height of the rafters is not enough for this, the installation of a counter-lattice (counter-batten) is provided.

Step-by-step instructions for performing work

The sequence of stages of building a roof is as follows:

making measurements of the building box (the dimensions may slightly differ from the design ones);
preparation of materials and tools, wood treatment with an antiseptic;
fastening the Mauerlat to the wall;
installation of a ridge girder, if needed (for layered rafters);
frame installation;
roof reinforcement with struts, struts and braces;
waterproofing;
lathing;
provision of ventilation;
installation of droppers;
installation of the coating.

Fixing the Mauerlat

In order for the roof to be securely fixed, you need to take care of its reliable connection to the building wall. If a wooden house is being erected, then a Mauerlat is not required - the upper crown of a bar or log acts as this element. In this case, the fastening to the wall is carried out using special “floating” fasteners. They are sold ready-made, most often they are called sleds. This version of the roof device allows the entire structure to move slightly during wall shrinkage without destruction and deformation.

"Sliding" fastening in a wooden house

A similar situation arises with a frame house. In this case, the top trim of the walls will be the Mauerlat. It is attached to the frame posts with a saw cut using corners, staples or nails.

Methods for attaching the rafters to the strapping in frame house

The roof structure of brick, concrete blocks or concrete implies anchorage through a Mauerlat. In this case, there are several ways.

You can put the Mauerlat on the wall in four ways:

on staples;
on hairpins;
on the anchor bolts.

Mauerlat can be fastened to staples. In this case, wooden blocks are laid in the masonry from the inside. They should be 4 rows from the edge. One side of the bracket is attached to the Mauerlat, and the other to the same bar in the masonry. The method can also be classified as simple. It is not recommended for large buildings with high loads.

Mounting the Mauerlat on staples. In the masonry of the wall, antiseptic wooden blocks are provided with a step of 1-1.5 m

Do-it-yourself fastening when installing the roof can be done through studs or anchor bolts with a diameter of 10-12 mm. Fasteners are laid in the masonry. A Mauerlat is temporarily laid on the edge, you need to lightly hit it with a hammer. After that, grooves remain on the bar in the places of fasteners. They need to make holes for the studs. After that, the bar is put on the fasteners and the nuts are tightened. The method is ideal for lightweight concrete walls in the presence of a monolithic armored belt.

Fastening the rafters to the Mauerlat

In houses made of brick or stone, it is wiser to perform it by rigidly attaching the rafters to the Mauerlat. In this case, you can use both a layered and a hanging system. The design involves two ways:

with a cut;
without cutting.

In the first case, the rafters are cut with a slope so that they fit tightly to the Mauerlat. For the removal of the cornice, filly are provided. They are attached to the leg with an overlap of at least 1 m. Rigid fixation of the knot should be done with self-tapping screws, nails or staples. But the assembled frame will be more reliable if metal corners with holes for self-tapping screws are used for fixing.

The no-cut method often does not involve the use of fillies. In this case, the overhang of the frame is provided by the beams themselves. This option is simpler than the previous one, since it does not require high accuracy. It is suitable for beginners. For a snug fit to the Mauerlat, in this case, persistent bars or boards are used. Rigid fixation, as in the previous case, is performed with metal corners on both sides.

Fastening the rafters to the wall

The made frame must be fixed to the building box - this will prevent a strong gust of wind from tearing off the roof. To do this, as a rule, you need to take the use of a twist of two wires with a diameter of 4 mm. They are wrapped around the leg in the place of support on the Mauerlat, and then the wire is attached to the wall on an anchor or ruff about 4-5 rows before the cut. The element must be laid in the masonry in advance.

Protection from being blown off by the wind

For a wooden house, you can simplify the task. You can assemble the frame using staples. This option will speed up the process. But it is important to remember that this method is suitable only if the walls are made of wood.

Strengthening the system

How to strengthen the frame for spans over 6 meters? It is necessary to reduce the free span of the rafters. For this, struts and struts are used. It is necessary to make reinforcement taking into account the layout, it is important that these elements do not interfere with the stay of people and harmoniously fit into the interior.

The braces are usually placed at an angle of 45 or 60 degrees to the horizontal plane. The uprights must not be supported on the floor span. They are allowed to be installed on the underlying walls or beams and trusses thrown between the walls.

Tightening is necessary to reduce the thrust. Because of him, the rafters can simply part. This is especially true for systems with hanging beams. To assemble the frame, use two puffs, which are attached on both sides of the rafters. Fixation is carried out on self-tapping screws, nails or pins.

At the top, the rafters rest on an intermediate or ridge girder. Depending on the chosen system, the location and width of the span, it is made from a bar with a section from 50x100 to 100x200 mm. Fastening is carried out on connecting metal plates, bolts or nails.

Lathing

Before starting work at this stage, it is required to lay waterproofing material... Builders recommend using a vapor-diffusion moisture-windproof membrane. It costs more than plastic wrap, but guarantees more reliable protection... Your home is not a reason to save money.

The roof requires securing the battens. The type depends on the selected roofing material. For metal, a sparse lathing of boards with a thickness of 32-40 mm will be enough. For bituminous shingles, a continuous sheathing made of a 25-32 mm board or moisture-resistant plywood is needed.

Ventilation of the roof space

Before proceeding to the stage of laying the roof, it is worth considering the ventilation of the under-roof space. This will protect the structures from mold, mildew and destruction.

Proper arrangement of ventilation under the roof will protect the structure from the appearance of fungus

For ventilation, you need to provide:

air flow through the cornice (the filing of the cornice is made with a thin board or special perforated soffits);
air movement under the covering (there should be a gap of 2-3 cm between the insulation and the roof);
air outlet in the area of \u200b\u200bthe ridge (for this, a ridge and / or point aerator is installed on the roof).

Roof covering

The type of roof is selected for aesthetic and economic reasons. It is also worth studying the manufacturers' proposals and finding out the permissible bias. For example, it is not recommended to lay bituminous shingles with a slope of more than 45 °.

Seam roofing is a lightweight fireproof and durable coating

The wall material must provide reliable waterproofing. Its installation is carried out in strict accordance with the manufacturer's instructions. There are five most common types of roofing: roof insulation.

Rafters perform a number of significant roofing functions. They set the configuration of the future roof, perceive atmospheric loads, and hold the material. Among the rafter duties, the formation of flat planes for laying the coating and providing space for the components of the roofing pie.

In order for such a valuable part of the roof to flawlessly cope with the listed tasks, information is needed about the rules and principles of its construction. The information is useful both for those who construct the rafter system of the gable roof with their own hands, and for those who decide to resort to the services of a hired team of builders.

In the device of the rafter frame for pitched roofs, wooden and metal beams... The starting material for the first option is a board, a log, a bar.

The second is constructed from rolled metal: a channel, shaped pipe, I-beam, corner. There are combined structures with the most loaded steel parts and timber elements in less critical areas.

In addition to the "iron" strength, the metal has a lot of disadvantages. These include thermal engineering qualities that do not satisfy the owners of residential buildings. The need for welded joints is disappointing. Most often, industrial buildings are equipped with steel rafters, less often private cabins assembled from metal modules.

In the case of self-construction of truss structures for private houses, wood is a priority. It is not difficult to work with it, it is lighter, "warmer", more attractive by environmental criteria. In addition, a welding machine and welder skills are not required to make nodal connections.

Rafters - a fundamental element

The main "player" of the frame for the construction of the roof is the rafter, among the roofers called the rafter leg. Beds, braces, headstock, purlins, tightenings, even a Mauerlat may or may not be used depending on the architectural complexity and dimensions of the roof.

The rafters used in the construction of the frame of gable roofs, according to technical characteristics and method of laying, are divided into:

Fortified rafter legs, both heels of which have reliable structural support under them. The lower edge of the layered rafter rests against the Mauerlat or the ceiling crown of the frame. The support for the upper edge can be a mirror analogue of the adjacent rafters or a girder, which is a beam horizontally laid under the ridge. In the first case, the rafter system is called spacer, in the second it is non-spacer.
Hanging rafters, the top of which rests against each other, and the bottom is based on an additional beam - a tightening. The latter connects the two lower heels of adjacent rafter legs, resulting in a triangular module called a rafter truss. Tightening dampens stretching processes, due to which only vertically directed loads act on the walls. The structure with hanging rafters, although it is a spacer, does not transfer the spacer itself to the walls.

In accordance with the technological specifics of rafter legs, structures constructed from them are divided into layered and hanging ones. For the stability of the structure, they are equipped with struts and additional racks.

For the device of the supports for the top of the layered rafters, the beds and girders are mounted. In reality, the rafter structure is much more complex than the described elementary templates.

Note that the formation of a gable roof frame can generally be performed without a rafter structure. In such situations, the alleged planes of the slopes are formed by slabs - beams laid directly on the supporting gables.

However, we are now specifically interested in the device of the rafter system of a gable roof, and it can involve both hanging or layered rafters, or a combination of both types.

The subtleties of attaching the rafter legs

The rafter system is fastened to brick, foam concrete, aerated concrete walls through the Mauerlat, which in turn is fixed with anchors.

Between the Mauerlat, which is a wooden frame, and the walls made of these materials, a waterproofing layer of roofing material, waterproofing, etc. is necessarily laid.

The top of the brick walls is sometimes specially laid out so that something like a low parapet is obtained along the outer perimeter. So it is necessary that the Mauerlat placed inside the parapet and the walls do not burst the rafter legs.

Roof frame rafters wooden houses rest on the top crown or on the ceiling beams. The connection in all cases is made by cuts and duplicated with nails, bolts, metal or wooden plates.

How to do without furious calculations?

It is highly desirable that the section and linear dimensions of wooden beams are determined by the project. The designer will give clear design justifications for the geometric parameters of the board or timber, taking into account the entire spectrum of loads and weather conditions. If available home master there is no design development, its path lies on the construction site of a house with a similar roofing structure.

You can ignore the number of storeys of the building being built. It is easier and more correct to find out the required dimensions from the foreman than to find out from the owners of shaky unauthorized construction. Indeed, in the hands of the foreman, the documentation with a clear calculation of the loads on 1m² of the roof in a particular region.

The step of installing the rafters determines the type and weight of the roofing. The heavier it is, the less the distance between the rafter legs should be. For laying clay tiles, for example, the optimal distance between the rafters will be 0.6-0.7 m, and for the profiled sheet, 1.5-2.0 m is permissible.

However, even if the step required for the correct installation of the roof is exceeded, there is a way out. This is a reinforcing counter-grid device. True, it will increase both the weight of the roof and the construction budget. Therefore, it is better to understand the step of the rafters before the construction of the rafter system.

Craftsmen calculate the step of the rafters according to design features buildings, corny dividing the length of the ramp into equal distances. For insulated roofs, the step between the rafters is selected based on the width of the insulation plates.

On our website you can find, which may also help you a lot during construction.

Roof structures of layered type

The rafter structures of the layered type are much simpler in execution than their hanging counterparts. A reasonable plus of the layered scheme is to provide full ventilation, which is directly related to the long-term service.

Distinctive design features:

Mandatory presence of support under the ridge heel of the rafter leg. The role of the support can be played by a purlin - a wooden beam resting on racks or on inner wall structures, or the upper end of the adjacent rafters.
The use of a Mauerlat for the construction of a truss structure on walls made of brick or artificial stone.
The use of additional girders and racks where rafter legs require additional support points due to the large size of the roof.

The disadvantage of the scheme is the presence of structural elements that affect the layout of the internal space of the operated attic.

If the attic is cold and the organization of useful premises is not expected in it, then the layered structure of the rafter system for the device of a gable roof should be preferred.

Typical work sequence for the construction of a layered rafter structure:

First of all, we measure the height of the building, the diagonals and the horizontality of the upper cut of the frame. If vertical deviations of brick and concrete walls are detected, we eliminate them with a cement-sand screed. We reduce the excess of the heights of the log house. By placing chips under the Mauerlat, vertical blemishes can be dealt with if their size is insignificant.
The overlap surface for laying the bed must also be leveled. He, the Mauerlat and the girder should be clearly horizontal, but the location of the listed elements in the same plane is not necessary.
We process all wooden parts of the structure before installation with fire retardants and antiseptic preparations.
On concrete and brick walls we lay waterproofing for the installation of the Mauerlat.
We lay the Mauerlat timber on the walls, measure out its diagonals. If necessary, slightly move the bars and turn the corners, trying to achieve the perfect geometry. Align the frame horizontally if necessary.
We mount the Mauerlat frame. The splicing of the beams into a single frame is carried out by means of oblique cuts, the joints are duplicated with bolts.
We fix the position of the Mauerlat. Fastening is made either with staples to wooden plugs laid in the wall ahead of time, or with anchor bolts.
We mark the position of the bed. Its axis should recede from the Mauerlat bars at equal distances on each side. If the girder rests only on racks without a bed, the marking procedure is carried out only for these posts.
We install the bed on a two-layer waterproofing. We fasten it to the base with anchor bolts, and connect it to the inner wall with wire twists or staples.
We mark the installation points of the rafter legs.
We cut out the racks to the same size, because The bed is on the horizon. The height of the racks should take into account the dimensions of the cross-section of the purlin and the bed.
We install racks. If provided by the project, we fasten them with spacers.
We put the run on the racks. Check the geometry again, then install the brackets, metal plates, wooden fixing plates.
We install a test rafter board, mark the cutting points on it. If the Mauerlat is set strictly to the horizon, there is no need to adjust the roof rafters in fact. The first board can be used as a template for the rest.
We mark the installation points of the rafters. For marking, folk craftsmen usually prepare a pair of rails, the length of which is equal to the gap between the rafters.
According to the markings, we install the rafter legs and fasten them first at the bottom to the Mauerlat, then at the top to the girder to each other. Every second rafter is screwed to the Mauerlat with a wire bundle. IN wooden houses The rafters are screwed to the second crown from the top row.

If the rafter system is made flawlessly, the planks are mounted in random order.

If there is no confidence in the ideal structure, then the extreme pairs of rafters are first installed. A control string or fishing line is pulled between them, according to which the position of the newly installed rafters is adjusted.

The installation of the rafter structure is completed by the installation of fillies, if the length of the rafter legs does not allow forming an overhang of the required length. By the way, for wooden buildings, the overhang should "go out" beyond the building contour by 50 cm. If the organization of the visor is planned, separate mini-rafters are installed under it.

Another useful video about building a gable rafter base with your own hands:

Hanging truss systems

The hanging type of rafter systems is a triangle. The two upper sides of the triangle are folded by a pair of rafters, and the tightening that connects the lower heels serves as the base.

The use of a tightening allows you to neutralize the action of the thrust, therefore, only the weight of the sheathing, the roof, plus the weight of precipitation, depending on the season, acts on the walls with hanging rafter structures.

The specifics of hanging truss systems

Characteristic features of hanging rafter structures:

The obligatory presence of a tightening, made most often from wood, less often from metal.
Ability to refuse to use Mauerlat. A timber frame will be successfully replaced by a board laid on a two-layer waterproofing board.
Installation on the walls of ready-made closed triangles - roof trusses.

The advantages of the hanging scheme include the space under the roof free of racks, which allows you to organize an attic without pillars and partitions. There are disadvantages.

The first of them is restrictions on the steepness of the slopes: the angle of their slope can be at least 1/6 of the span of a triangular truss, steeper roofs are strongly recommended. The second disadvantage is the need for thorough calculations for the competent device of the cornice nodes.

Among other things, the angle of the truss truss will have to be set with jewelry precision, because the axes of the connected components of the hanging rafter system must intersect at a point, the projection of which must fall on the central axis of the Mauerlat or the lining board replacing it.

Subtleties of large-span hanging systems

The brace is the longest element of the hanging truss structure. Over time, as is typical for all lumber, it deforms and sags under the influence of its own weight.

The owners of houses with spans of 3-5m are not too worried about this, but owners of buildings with spans of 6 or more meters should think about installing additional parts that exclude geometric changes in tightening.

There is a very significant component to prevent sagging in the rafter system installation scheme for a large-span gable roof. This is a suspension called a headstock.

Most often, it is a bar attached with wooden beads to the top of a truss. The headstock should not be confused with the racks, because its lower part should not come into contact with the puff at all. And the installation of racks as supports in hanging systems is not used.

The bottom line is that the headstock seems to hang on the ridge knot, and a tightening is already attached to it with the help of bolts or nailed wooden pads. Threaded or collet type clamps are used to correct the slack.

Adjustment of the tightening position can be arranged in the area of \u200b\u200bthe ridge assembly, and the headstock is rigidly connected to it with a cut. Instead of a bar in non-residential attics, reinforcement can be used to manufacture the described tightening element. It is recommended to arrange a headstock or a suspension even where the tightening is assembled from two bars to support the connection section.

In an improved hanging system of this type, the headstock is supplemented by strut beams. The stress forces in the resulting rhombus are extinguished spontaneously due to the competent arrangement of the vector loads acting on the system.

As a result, the rafter system pleases with stability with minor and not too expensive modernization.

Hanging type for attics

In order to increase the usable space, the tightening of the truss triangles for the attic is moved closer to the ridge. A reasonable move has additional benefits: it allows puffs to be used as a basis for ceiling filing.

It is connected to the rafters by cutting it with a semi-rotary screw with a duplicating bolt. It is protected from sagging by installing a short headstock.

A tangible disadvantage of the attic hanging structure is the need for accurate calculations. It is too difficult to calculate it yourself, it is better to use a ready-made project.

Which design is more cost effective?

Cost is an important argument for an independent builder. Naturally, the price of a structure for both types of truss systems cannot be the same, because:

In the construction of a layered structure for the manufacture of rafter legs, a board or a beam of a small section is used. Because layered rafters have two reliable supports under them, the requirements for their power are lower than in the hanging version.
In the construction of a hanging structure, rafters are made of thick beams. For the manufacture of a puff, a material similar in section is required. Even taking into account the abandonment of the Mauerlat, the consumption will be noticeably higher.

It will not work to save on the grade of the material. For the supporting elements of both systems: rafters, girders, bedsteads, Mauerlat, attendants, racks, 2nd grade lumber is needed.

For crossbars and tension rods, grade 1 is required. In the manufacture of less critical wooden linings, the 3rd grade can be used. Without counting, we can say that expensive material is used to a greater extent in the construction of hanging systems.

Hanging trusses are assembled in an open area next to the object, then transported assembled upstairs. To lift weighty triangular arches from a bar, you will need equipment, which you will have to pay for rent. And the project for complex nodes of the hanging version is also worth something.

Video instruction on the device of the hanging category truss structure:

There are actually much more methods for constructing truss systems for roofs with two slopes.

We have described only the basic varieties, which in reality are applicable for small country houses and buildings without architectural ideas. However, the information provided is sufficient to cope with the construction of a simple truss structure.

Before considering how to make a roof with your own hands, you need to decide on the meanings of the words "roof" and "roof": is there a difference between them and what is. A practical owner, wanting to reduce construction costs, seeks to do most of the work on his own, without involving professionals and the correct understanding of terms and designations in construction works he just needs it. Therefore, it is so important to have high-quality information on how to properly perform the installation of one or another architectural element of a house under construction.

The roof is the most important structural element of the house, providing protection from environmental influences and defining the aesthetic appearance of the building.

So, the roof is the upper part of the building, which closes the interior from the environment, and the roof is the top covering of the roof made of moisture and windproof cover.

Therefore, the meanings of these words are completely different. A self-built roof is the pride of every owner. But in order for it to be durable and really decorate the building, you need to know how it is made.

Types of pitched roofs

Roofs are of two types: flat and pitched. Since the first ones are rarely erected by developers, we will consider in more detail what kind of roofs with slopes are:

The shed system is a rather rare choice. It slopes from one wall to the other. Private developers often build them for garages, sheds, utility rooms... In urban housing construction, they are used where it is undesirable to arrange drainage systems and discharge snow.
A gable roof of a house is the most common option. It is used everywhere.
Half-hip (four-slope) is an indispensable attribute of country houses.
Four-slope hipped roof is a structure, the slopes of which are connected to each other at one point and descend along different sides of the building.
The spire-like system is formed in the form of several steep triangular slopes, connecting at one point. Used in the construction of towers, bay windows, buildings with round walls.

What you need to know when choosing a roof structure with slopes

The higher the slope angle at the roof, the less time the snow will remain on it, and accordingly create lower loads.

If the slope angle exceeds 50 degrees, then the snow will not linger on it. Accordingly, the load on the roof during the cold season will be insignificant. This means that in the calculations, you can lay a lower strength factor of the rafters and save on building materials.
For roofs with a 20-degree slope of the slopes, the cross-section of the rafters should be maximum, since such a structure will have to withstand significant loads.
The fire safety requirements for roofs are as follows: when exposed to open fire, it must withstand it without much damage to itself for 15-30 minutes. In order for your design to meet this indicator, know that the fire resistance limit is higher for roofs with rafters of the maximum cross-section, treated with a fire retardant compound.
If the house is being built in the northern region, then the roof should provide for high-quality insulation. Consequently, the load on the structural elements of the roof will increase. This must be taken into account when choosing a building material.
The smaller the angle of the slope, the greater the consumption of roofing materials, since the overlap between the covering sheets in this case should be wider.
The steeper the roof, the longer the overhang is required. It protects the walls of the building from rainwater and snow falling on them.
When deciding on the choice of the type of roof, first of all think about the material for the roof. Its weight determines which rafter scheme to choose. The heaviest roof is made of ceramic tiles. For her we make a reinforced roof structure and a strong foundation.

Installation of a gable roof structure

Consider how to make the most common type of roof of a house with your own hands with the following scheme for laying rafters: they fit onto the floor beams of the upper floor of the house.

Installing Mauerlat

Diagram of a gable roof device.

With its installation, the construction of any roof begins. The builders call this structural element and in a different way: matitsa, murlat, uterus, etc. Mauerlat is a wooden bar with a section of 150x100 or 150x150 mm, which is installed on the walls of the house. It is designed to distribute the load from the weight of the roof, including snow and wind, on the walls of the building. It is necessary to lay the timber along the inner edge of the wall on a double layer of roofing material, and from the outside, the tree should be protected from the adverse effects of the environment using a row brickwork or waterproofing and facing material.

Often the developer has a question: is it necessary to fasten the Mauerlat to the walls? Since the roof always weighs quite a lot, this timber, as many think, will not go anywhere. But you need to fix it, because in the event of a hurricane, your house may well be left without a roof: it will simply be blown away by the wind. There are several ways of attaching the Mauerlat to the walls. In practice, the following are most often used:

If the building is built of bricks, then a competent builder, completing the laying of the walls, will certainly brick up wooden bars in the 2-3 row from the top. The Mauerlat will be attached to them with the help of vertically installed brackets.
If the house is made of foam or aerated concrete, then a belt of reinforced concrete must be made over the walls. During its installation, threaded rods must be installed at a distance of 1.5-2 m (at least). Holes are drilled in the timber for them, it is laid on the studs and attracted to the walls with nuts.

Before you install the bars on the walls with your own hands, they need to be fastened together. This is done as follows: we cut out half the thickness of the tree from both ends of the segments of 10-15 cm and we spliced \u200b\u200bthe bars together, fastening them with bolts or nails. When installing the mat, it is important to take into account that its upper part should protrude 2-3 cm above the wall surface. This will ensure that the weight of the roof is transferred to the Mauerlat, and not to the walls.

Install floor beams

The angle of inclination of the gable roof must be at least 35 degrees.

They are bars with a section of 200x100 or 150x100 mm. The length of the beams should be such that, when laid on the walls, they form an extension corresponding to the width of the future cornice. In most cases, it is 40-50 cm. Simply put, these bars should be more than the length of the house by a certain distance. The beams are installed in one direction at regular intervals. This work must be done in strict sequence:

First, we lay the beams with our own hands at the opposite walls, stepping back 50-60 cm from their edge.
We pull a cord between the extreme beams, which will serve as a guide for installing the following ones.
If the timber does not lie exactly on the hay, then you can put wooden dies under it and hang the Mauerlat in this place.
The distance between the beams is selected taking into account the step and section of the future rafters. For example, if it is decided to mount the rafters from "floor" boards 50x150 mm, then the step will be 60 cm. This is the most the best option, which greatly simplifies further work, since the width of the roofing insulation is also 60 cm. In this case, it does not have to be cut and extended.
Now we mount with our own hands the transverse beams, which are joined at one end with the extreme beam, and with the other they extend beyond the wall to the distance of the cornice from the side of the gables. The distance between these jumpers is 1 m.
We pull all floor beams to the Mauerlat with 150 nails, steel corners or self-tapping screws.
In order to make it easy to move around during work, we lay ordinary boards on the beams.

We install the ridge bar

We begin to mount auxiliary racks with our own hands. They are U-shaped wooden struts, the height of which should correspond to the height at which it is planned to install the ridge, that is, the height of the roof. Professionals advise taking it equal to the height of the first floor (from the ground to the Mauerlat, if the house is one-story).
First, we assemble with our own hands and install racks on opposite sides of the roof.
Then we pull a cord between them and set intermediate ones along it with a step of 2.5-3 m.
When all the racks of the truss are installed, we put the ridge beam on them, strictly in the middle. Usually it is a 50x200 or 50x150 mm board. It does not need to be firmly attached to the auxiliary posts. For now, a few screws will suffice.

Installation of the rafter system

Gable roof rafter system.

Since the rafters must be strictly the same length, before starting work, we make a template with our own hands, according to which we will measure them. To do this, take a 25x150 board and attach it with one end to the ridge, and the other to the beam. In the places of contact, we will put marks and saw off the board along them. Despite the fact that we will need a template and will greatly facilitate the work, it is still difficult to achieve a strict geometric structure of the building and more than once we will have to adjust the length of the rafters.

Having installed the rafter from one roof slope, after it we install the opposite one on the other slope. This will relieve the load on the ridge bar. If you do not adhere to this sequence, then the skate will bend and the design will turn out to be unreliable. If the slope is very long (more than 6 m) and the standard length of the boards for the rafters is not enough, this problem can be solved in two ways:

order a longer material on the sawmill;
splicing together two available boards, sewing on them a piece of exactly the same material.

We attach each rafter to the horse beam with a couple of nails. In order to pull it to the beam with our own hands, we use fastening iron plates or self-tapping screws for wood. It is undesirable to use steel staples in these works, as they "work" in tension.

We reinforce each rafter by installing a support post closer to the beam. If we have an attic roof, these racks will be the basis for the side walls.

We are working on the device of gables and hemming the cornice

We will make waterproofing and crate

With strict adherence to the sequence and the correct execution of all work, the roof of your house will be in no way inferior to that which would have been made by professionals.

for the convenience of work around the perimeter of the house, you need to install scaffolding;
we lay the first waterproofing layer on the rafters: a special film and fix it with a construction stapler;
we take slats of 25x50 mm and begin to mount the counter-lattice with our own hands. There should be no problems with this, since each roofing material comes with instructions on how to do it yourself;
on the counter-lattice we install vertical posts from the same rail. Thus, we get a full-fledged crate;
we make a pediment overhang and ebb:

We sew a 25x150 board from the bottom to the ends of the crate protruding from the side of the pediment. This will be the gable overhang wind board.
We install lintels along the entire height of the pediment, which the builders call "filly". They should be 1 m apart from each other.
We fasten boards 25x150 in two layers to the filly from below with our own hands. We will mount siding or other facing material on them.
We will make a gable ebb with the help of pre-prepared triangular fillies. We also sheathe it with a double layer of boards 25x150.

Installation of roofing material

The choice here is not too large: metal tiles, profiled metal profiles, ceramic tiles, slate, ondulin, galvanized iron. All of them are strong, durable, waterproof. Which one to buy depends on the preference of the home owner. Consider how to mount it yourself roofing material on the example of corrugated board.

Corrugated roofing: choose the material

Let's pay attention to the thickness of the sheet and its brand. For a light roof, it is recommended to choose sheets of grade C8, C10, C13, C18, C25 and C44. If you need a more durable coating, then buy HC35 or HC44. The waveform can be either trapezoidal or sinusoidal. Wave height should be 20 mm or more. The color of the corrugated board should be in harmony with the color scheme facing material the whole house.

We calculate the amount of material based on the area of \u200b\u200bone sheet of corrugated board that you will buy. In the calculations, it is necessary to take into account that the roofing is mounted with an overlap of 10-15 cm. Plus, you need to lay a margin of 4-5% of the roof area of \u200b\u200bthe house. For a gable structure, it is quite easy to calculate how much material is needed. But if the roof is complex, broken, then you need to turn this question to professionals.

Necessary additional elements:

end plate;
cornice strip;
gutter bar;
abutment strips;
endova;
snow retention strips;
ridge elements.

Installation of corrugated board on the roof

Safety rules: you need to move in soft shoes strictly along the grooves between the waves. We work with gloves, as the edges of the sheets are sharp.
We start installation of corrugated sheets from the bottom of the ramp. We lay the first layer of sheets over its entire width with our own hands. The roof is overlapped by 1-2 waves.
Fasteners - self-tapping screws with rubber gaskets. We screw them only into the grooves between the waves.
The upper tier of corrugated board sheets is laid with an overlap of at least 15 cm on the lower one.
We mount the ridge element with our own hands: if the slope of the roof slopes is small, then we use a rubber seal. The overlap of the ridge on the corrugated board must be at least 20 cm.
We begin the installation of the junction strips from the bottom of the pipe. We cut the brick, wash the seam, put one edge of the plank into the pipe. We fix it with a connecting tape, attach it to the corrugated board. This is done gable roof do it yourself.