Gable roof all options. Features of the rafter system of a gable roof. Insulation and protection from water

The roof is one of the main elements of the house, along with the walls and foundation. Without its correct arrangement, the house will not be strong enough and comfortable to live in. The result of a bad roof will be dampness, wet walls, all kinds of diseases and additional heating costs.

The preferred type of roof depends on the climate of the area, the prevailing weather conditions. The most common in our conditions are gable ones, which are quite simple to construct and maintain, and reduce the load from snow or other heavenly moisture. Aesthetics play an important role in choosing them.

Types of gable roofs

A gable roof is a fairly simple structure, consisting of two slopes connected to each other at an angle. They form something like a triangle. But despite the simplicity of this figure, triangles are different. Gable roofs also differ from each other.

The main difference between their designs is the angle of inclination. Depending on the type of building and other necessary conditions it may vary. In addition, the angles at which the slopes are installed may differ from each other. As a result, one of the following types is built:

Simple symmetrical;
Simple asymmetrical;
Broken (the break can be either internal or external).

Each type has its own positive and negative sides, forcing you to choose one builder or another depending on the circumstances.

Simple symmetrical roof

Simple symmetrical roof

This type of construction is undoubtedly the most common. It is the easiest option to make yourself. His appearance always looks good. In the end, it is also good because under such a roof there remains a lot of useful attic space.

The name of the structure shows what its distinctive feature is: the slopes form an isosceles triangle. The symmetry of this figure allows it to look proportional on any home.

Simple asymmetrical roof

The main difference from the previous version is also directly reflected in the name. The ridge of this type of roof is shifted to the side and, as a result, the triangle formed by it turns from isosceles to scalene. This design looks modern, so it is well suited for homes in a modern style.

An asymmetrical roof has two important features:

Reducing the size of attic spaces;
Unequal load distribution.

As a result, this type of design is good for those who need extra space for rooms that can go right up to the roof. But it requires correct calculations.

broken roof

broken roof

This type of construction is the most complex, so not everyone decides to do it with their own hands. Although, in fact, this is quite possible. It’s just important to carry out the correct calculations from the beginning. After all, the main feature is its irregular shape, where the loads are distributed extremely unevenly.

The main advantage sloping roof, in addition to its varied appearance, is that it provides maximum free space underneath. As a result, it is possible to equip a full-fledged residential second floor, an attic. Thanks to this feature, it is also called attic.

Rafter system design

The rafter system is the basis of the roof. There are two main design solutions for rafters gable roof:

Hanging.

Design rafter system gable roof

The first of them is used when the house has internal supports, for example, load-bearing walls. In case of their absence, the hanging type is preferable.

But, regardless of what type of rafter system it is decided to build, everyone who wants to know how to build a roof with their own hands must understand the main elements of the structure. Namely:

Rafter leg or simply rafters. Rafter legs are the basis of the design of the entire system. They are placed on top, along the building, and connected to each other to form a truss. Since they are the ones that support the roof covering, it is important to use durable wood here too. It is desirable that it be a log or timber. Installation is carried out based on pre-made calculations, since it will be very difficult to change something later;
Rafter post. This structural element helps distribute the load from the rafters. It is a vertically located beam. Its location depends on the type of structure the roof has and its size. If we are talking about a simple symmetrical roof with a small span, then the rack is installed in the center. If the width is large, then two additional ones are placed on the sides. The asymmetrical version involves the location of this element depending on the length of the rafters, and the broken one - two on the sides. True, if there are more than one rooms, then in the latter case an additional rack in the center is needed;
Run. the main task purlins connect the rafters, simultaneously giving them rigidity. The purlins can be ridge or side. The first is located at the very top of the roof, in the area of its ridge. They make purlins from timber. Sometimes boards are used. The most common section is 50 by 150 mm. If the girder is made not only with a ridge, but from several beams or boards on the sides with a large length of the roof, then they are supported by a stand coming from the ridge and resting on the beam. The side purlins are connected to it by means of struts;
Strut. They are a structure made of beams located at a certain angle and resting on a bench. Their main task is to serve as supports for racks. Can be diagonal or longitudinal. The latter are used most often; they are on the same plane as the rafters. At the same time, the former are necessary if there is an increased snow or wind load in the area. With it, it is also advisable to choose a brace angle of 45 degrees;
Sill. Located at the very bottom of the structure. If possible, it is placed on an internal load-bearing wall. Its main purpose is to serve as a support for racks. Slopes are attached to it;
Puff. This element connects the rafter legs, located perpendicularly under them. At the same time, it provides greater structural rigidity;
Rigel. It also connects the rafter legs, but unlike the tightening, not from below, but from above. Installed with overlap. They make a crossbar from a board of the same cross-section as the rafters themselves;
Lathing. This element is installed at the final stage of assembling the truss structure, since it is the basis for the covering. It consists of beams and boards that parallelly connect the rafters from top to bottom. In addition to the fact that it serves to secure the roof, the sheathing helps to redistribute the load from it. Therefore, the distance between the elements depends on the material that will be used for coating.

A general understanding of the meaning of each structural element will greatly facilitate the task of building a gable roof with your own hands.

Calculations

Calculation of the load on various roof elements is the most important stage, since the strength and safety of the structure depends on it. It must be remembered that the triangle is its toughest part.

Loads on rafters can be of three types:

Permanent. These are the loads that the rafters feel constantly. For example, the weight of finishing and roofing materials, sheathing, etc. In order to recognize it, it is enough to add up all these weights. Typically the constant load is about 40 kg/m2;
Variables. They operate in different time with different strengths. These include, for example, wind. In order to calculate the wind load or the load from precipitation, you need to look at the SNiP;
Special. We are talking about loads associated with increased seismic activity.

When calculating the load exerted by snow, its weight is multiplied by a set correction factor that takes into account wind pressure. A coefficient depending on the angle of inclination of the roof is also introduced - the lower it is, the greater the load. If the angle exceeds 60 degrees, it is not taken into account.

Tilt angle

The correct calculation of the angle of inclination depends on certain features. Firstly, a lot depends on the chosen material. So, ondulin, corrugated sheets, metal tiles, slate require an angle of 20–45 degrees. A soft roof- up to 20 degrees.

Secondly, the angle of inclination depends on the climate in which the roof is being built. If there is little precipitation, then you can make it insignificant. And with a large number, it’s the other way around. But it is worth remembering that large angles are subject to large wind loads.

Rafter length

Calculating the length of the rafters is not particularly difficult. It is based on the Pythagorean theorem. The length of the rafter is taken as the hypotenuse of the triangle. And the role of the legs is played by the height of the roof and half the width of the house. It’s worth adding a few tens of centimeters to the resulting value.

Rafter foot step

Their choice depends on the weight of the structure used to cover the roof and the material used. Usually it varies between 60-100 cm.

Rafter section

Calculating the correct required rafter section is one of the most important points, since this indicator greatly affects the reliability of the design. This takes into account:

Loads;
Rafter length;
Rafter pitch;
Material used;
The type of wood used in the construction of the house.

The higher the pitch of the rafter legs, the higher the cross-section.
The video provides a detailed description of the calculation of the rafter system.

Types of rafter systems

There are two main types of rafter systems from which to choose when erecting a gable roof. We are talking about hanging and layered rafters. Each type is designed for different structures.

Hanging structure

Hanging rafter system

Hanging ones are designed for small houses whose width does not exceed 6–6.5 linear meters. They are not suitable for houses with a wide roof. They are also not used where there is a middle load-bearing wall.

Design features

A design feature of hanging rafters is that they rest on the two outer load-bearing walls. As a result, the system is subject to a strong bursting force. If necessary, it is lowered using a bolt attached at the bottom.

Attaching to the Mauerlat

The design feature of hanging rafters also dictates how they are attached to the “foundation” of the entire system - the mauerlat. The only mounting option is to use a unit with a zero degree of freedom. Hinges, for example, cannot be used.

Layered system

Layered rafter system

Layered rafters are the only option when it comes to a large roof. But they either require an internal load-bearing wall or specially installed intermediate supports. A support is laid parallel to the Mauerlat, which takes on part of the load from the structure.

Differences between hanging and layered rafters

Hanging rafters do not require intermediate supports or an internal load-bearing wall, but their bursting force greatly influences the structure. At the same time, due to the fact that they also rest on a beam in the middle, layered rafters are easier, including in assembly. They are better suited for larger roofs.

DIY gable roof installation

As already noted, a gable roof is especially popular due to the fact that its design allows you to build it yourself. Which is naturally quite attractive for those who like to build themselves or want to save a lot.
The construction of a gable roof structure consists of several large stages, each of which is important to perform correctly. In this case, the roof will stand for a long time and will not collapse.

Installation and fastening of the Mauerlat

Formally, a gable roof can be made without a Mauerlat. In this case, the rafters will rest on the floor beams. But it is not recommended to do this one simple at a time, but important reason- the beams will have to take on additional load from the roof.
The Mauerlat is installed along the wall on which the rafters will rest, parallel to the ridge of the house, as shown in the photo.

Mauerlat

Mauerlat connection

The ends of the beams that will be connected are sawn at an angle of 90 degrees. After the ends are applied to each other, they are fastened with bolts and only with bolts. It is important not to use any other material, such as nails or wire, instead of bolts.

Fastening

The methods for attaching the Mauerlat are based on the fact that it is installed on top of the wall. At the same time, it can be located either strictly in the center of the wall or offset to one of the edges. But it is important to maintain a distance of five centimeters to the outer edge.

A layer of waterproofing is placed between the wall and the timber. A simple roofing material is quite suitable for this.

This will protect the wood from the influence of moisture that may fall on the walls. The mount itself must be as strong as possible, because it will have to withstand wind loads. There are several ways to fix the Mauerlat to the wall.
The methods of attaching the Mauerlat to the walls largely depend on what material the house is being built from.

If the building is erected from a monolith, then the best solution are anchor bolts;
If the house is being built from timber, then the usual solution is wooden dowels. They can be strengthened with additional fastening;
A fairly common fastening option is staples. They are loved because they are quite versatile, although they are not the most durable solution;
If the building is constructed from porous materials, such as foam concrete, then the right choice would be to attach the Mauerlat to the reinforcement;
The hinged fastening, due to the fact that it is sliding, is suitable primarily for those houses that are built from materials that give noticeable shrinkage;
As an additional fastening, you can use strong, for example, knitting wire. It is not used as an independent option.

The correct choice of fastening will allow the roof to survive the blows of even the strongest winds.

Installation of rafters and racks

There are two options for assembling rafter legs. They can be collected either from above, on the roof, or below, on the ground. The second option is easier to do with your own hands, but it takes more time. The second will require the use of mechanisms, since it is difficult to lift the structure of the rafter system upward manually.

But, one way or another, the manufacture of rafters must be done strictly according to the markings. Special templates that are made from plywood after all the calculations have been made are well suited for this.

Rafter fastening diagram

Before attaching the rafter legs to the mauerlat, you need to make a gash in them. Only rafters can be sawed, since such procedures on the Mauerlat weaken it. Three nails are used for fastening. Two of them are driven in at the edges, and the third must be driven through the upper plane of the structure in the center. Thanks to the use of three nails driven in this way, the rafter leg is well attracted to the mauerlat and does not move.

As for the upper fastening of the rafters to each other, there are three main ways to do this.

Without support beam. Rafters can be spliced end-to-end or overlapped. In the first case, the ends are cut so that equal angles are formed. After applying the ends to each other, they are connected using a metal or wooden strip. In addition, a nail is driven in at the top. When joining with an overlap, the ends are cut as required and connected with bolts;
Using a support beam. This method is necessary if we are talking about a large roof. The rafters at the ridge are also attached end-to-end or overlapping, but in addition they rest on a beam, which in turn also serves as a support for the racks;
Cutting method. It involves cutting the rafter legs into the support beam.

The ridge support is mounted after the two outer rafter legs are installed. Then the racks are attached. And then, the remaining rafters. You can see all this in the photo or video.

Insulation and protection from water

Proper insulation and waterproofing are very important in the domestic climate. Especially when it comes to a roof that is constantly and heavily exposed to environment. And the moisture that accumulates in the house itself also rises to the attic in the form of steam.

Based on the above, it is important to choose insulation that has a vapor barrier function. Otherwise, its type does not matter. But as for waterproofing, roll types are considered the most suitable. For example, a special film. It can be easily laid directly on the rafters. You can see how this is done in the video.

Installation of sheathing

The sheathing is installed last, but it plays an important role.

Without it, it is inconvenient to move on the roof, and the roofing material puts unnecessary pressure on the rafters. In addition, it makes it possible for air cushion between roofing material and insulation.

The design of the sheathing and its pitch depend on what material will be laid on the roof.

The lattice sheathing is laid under slate, tiles or metal tiles, and corrugated sheets. In the case of metal tiles, the distance should be 350 mm, and for slate and corrugated sheets - 400 mm;
Solid sheathing is used for soft types of covering.

Installation of sheathing

It is made from timber or boards, and if we are talking about soft ones, from plywood, OSB sheets or the same board. They are laid on a beam located along the rafters, as shown in the photo and video.

Calculation of roof area

A gable roof often has a simple shape, so calculating its area is not difficult. But it is extremely important to do this accurately, because the consumption of materials depends on knowledge of the area.

Calculation of roof area

When calculating the roof area, in order to avoid confusion, you should not pay attention to the parameters of various ventilation openings, roof windows or chimneys. You just need to know the height from the ceiling to the ridge and the length of the ridge run. These parameters are multiplied. If you divide the roof area by the sine of the rafter angle, you can find out the area of one slope.

Typical parameters

A design feature that distinguishes a gable roof is that it can be divided into separate standard parts. By calculating the area of each such element separately and adding everything together, you can get the required amount of materials.

Since the roof is made with a slope, you need to know its angle.

The cosine of the angle is needed to determine the exact area of almost all elements.

Typical elements are the rafter legs that form the base of the trusses. In addition to them, there are braces, struts, supports, purlins.

Roofing: selection and installation

Installation of metal roofing

Installation of the roofing is the final stage of the work. But it is preceded by the selection of suitable material. Nowadays, manufacturers offer a huge selection of roofing materials, each of which has its own pros and cons. The choice is always up to the consumer and depends on his aesthetic preferences, financial capabilities and climate.

Natural tiles. This is a very beautiful, traditional, but at the same time expensive material. Its high price is compensated by a very long service life, unless, of course, it is deliberately damaged or it is exposed to extremely unfavorable weather conditions;
Metal coating. This roofing is also a fairly traditional solution. Today, manufacturers offer many options for metal roof sheets, differing not only in strength, but also in appearance;
Wooden roof. A shingle or spindle roof certainly has many aesthetic benefits. But it is quite expensive and susceptible to rotting without special treatment;
Self-leveling coating. It is considered quite inexpensive and reliable. Belongs to the category of soft coverings. The disadvantage is that it can only be used on roofs with not very steep slopes.

Each type of material is installed in its own way and different fastenings are used for them. Information can be obtained from the video or from the manufacturer. Then the eaves overhangs are installed.

Fastening parts

The ability to correctly fasten the smallest details is the most important in making a roof with your own hands. There are several basic methods for connecting and fastening parts of a roof structure.

So, a groove connection is used to fasten diagonal parts. If we are talking about connecting perpendicular elements, then it is suitable only for those of them where strength is not so important.

Metal corners and plates are also quite popular. They are distinguished by good strength. But the disadvantage is the danger that some screws will turn out from the load. To minimize risks, a combined fastening method is used.

Cost of a gable roof

The cost varies greatly depending on whether the roof is done with your own hands or with the help of craftsmen. In the latter case, it will be significantly more expensive and the price can reach several hundred thousand. In the first case, the main costs will go to materials.

The total price of the structure includes:

Materials;
Installation of the Mauerlat;
Installation of rafter system;
Installation of waterproofing;
Installation of sheathing;
Roof installation.

Carrying out any of these elements yourself reduces the cost of construction.

Finishing the gable with siding

The gable is a prominent part of the house. Therefore, it is customary to use attractive materials for its cladding. This could be a board that matches the roof, plywood or siding. When wooden houses the pediment can be cut in advance. This is explained in more detail in the video.
Thanks to the simplicity and accessibility of the design, which allows you to install it yourself, the gable roof has become a truly universal solution. Knowledge of individual features will make it easy to avoid the main problems during its construction.

It is called a structure consisting of a pair of slopes.

This type of roof is also known as a gable roof. Speaking in simple language, the gable roof is a triangle, which is closed at the top by a ridge. This roofing option is one of the most convenient and simple options and has been considered relevant for more than one century.

The gable roof is considered the most popular, and its construction is the simplest.

Types of gable roofs

Classification of gable roofs

sloping (mansard) gable roof;
gable symmetrical roof;
gable asymmetrical roof.

The first type is often used when constructing a gable attic (broken) roof, since this type of construction leaves a large space in the attic. A symmetrical roof is the most traditional option, based on an isosceles triangle. In the case of the latter design, the ridge is not located in the center, but with a slight offset. This option has an original and unusual look, although it does not leave much useful attic space.

In addition to the above, other, more bizarre and rare designs can be used in construction. One of these is a multi-level gable roof, the slopes of which do not converge at the ridge, but form a broken structure, ending at different heights. Such a roof, of course, looks impressive, but to create it you need to have impressive construction experience. The same applies to such an option as a gable semi-hip roof, which at first glance seems like an ordinary gable roof, but it has beveled elements along the edges of the ridge.

Roof slope angle

For these types of structures, the most important characteristic is the slope angle. with a small slope angle are most suitable for areas with a temperate or dry climate with little precipitation. If the house is being built in a very humid area with very frequent rains, then it is better to make the slope steeper, about 60 degrees, so that water does not accumulate on the surface of the roof and flows down as quickly as possible. In this case, you need to pay attention to the fact that a large slope leads to increased exposure to wind on the roof. To correctly calculate the design of a gable roof, it is necessary to take into account the sum of all maximum loads.

In addition, the choice of roofing also depends on the slope angle. For example, on a roof with a large slope, it is best to use tiles.

Features of the gable roof rafter system

When erecting a gable roof structure, only the most important parts of the rafter system are needed, namely the Mauerlat and the frame itself (rafters with struts). To make them, you need to acquire high-quality wood in the form of beams 150x150 and boards with a section size of 50x150 millimeters.

The frame of a gable roof can be made in two ways:

layered;
hanging.

The layered type of rafter system is most often used in buildings that have internal load-bearing walls. It can be used as intermediate supports. If the roof width does not exceed ten meters, then one support will be required for its construction; if the roof is more than ten meters wide, then the number of supports increases proportionally. The hanging type of rafter system is more suitable for buildings that do not have internal load-bearing walls. The frame of such a roof consists of two belts: the upper one, on which there are two rafters, and the lower one, consisting of rigidly connected puffs. The rafters of such a roof rest on the mauerlat, and the ends of the rafters end up on the outer walls.

The frame of a gable and sloping roof can be strengthened by creating support frames. They do not allow inclined elements to sag and significantly increase the strength of the structure. Sometimes attic walls are installed to the supporting frames (at). In addition, located above the carrier internal wall the support frame relieves part of the total roof load from itself.

How to correctly calculate the frame of a gable roof of a house?

The most standard and simplest option provides that the design is based on an isosceles triangle. In this case, the presence of a school base is sufficient for calculations.

As the famous Pythagorean theorem states, altitude divides an isosceles triangle into two equal rectangles. It follows from this that you need to know the width of the roof and its height to the ridge. Then you can calculate the roof surface area and calculate the required amount of building materials. In the calculations, it is also necessary to take into account allowances for the cornice and the placement of overlapping material.

Personal construction of a gable roof of a house

Stages of construction work

You can move from theory to practice. The first step is to start laying the floor beams. It is necessary to choose a building material taking into account the further use of the attic space: for the purpose of constructing a utility room, ordinary boards are used as material, and for constructing an attic (in the case of a sloping roof), thicker beams resting on the load-bearing walls are required.

The building's perimeter is equipped with a mauerlat, which is fixed with anchors. It will be possible to make nests for support beams in it.

Then you can move on to working on the trusses. They can be made in advance and simply raised on the roof, or they can be made directly during the process.

Please note that the gables must be done before. Just like rafters, they are made from wooden planks with a section size of 50x150 mm.

As a rule, the rafters are positioned so that the top rests on the ridge, and the bottom rests on the mauerlat. If this is not possible, you can use additional elements called thrust bearings. This way the rafters, resting against the floor beam, will be attached more firmly and reliably.

A special connection is made at the top of the rafter system, called a “lock”. To ensure maximum strength, headstocks and crossbars are used for construction.

Screws, nails, and wire can be used as fastening materials.

During construction, you can use the following useful tips:

The position of each rafter can be controlled using a plumb line.
Installation must begin with opposite trusses, between which a guide cord is pulled.
Sometimes you can use struts that rest against the middle of the rafter leg and the post and are secured with nails. This way the frame becomes more rigid.
It is more convenient to prepare the rafters in advance so that they are symmetrical and identical. But still with a slight error, so that each individual element can be adjusted on site with greater accuracy.
Upon completion of the work, you can proceed to installing insulation and laying roofing material.
Insulation and waterproofing device.

Waterproofing and roof insulation

To create reliable waterproofing, it is best to use a special film as a material. There are types with diffusion membranes or double-circuit ventilation.

Since moist and warm air from below enters the attic, the insulation material must be protected on both sides from moisture. For this purpose, vapor barrier systems are used, which do not allow liquid to accumulate in the hygroscopic layer of the material.

For insulation purposes, both bulk and rolled material can be used. The most popular material among builders is mineral wool. Keep in mind that when working with this material, you must wear a protective mask and construction gloves, since the dust released from the cotton wool during installation is harmful to the mucous membranes of the respiratory tract, and the skin of your hands can be damaged by the splinters with which this material is strewn.

House roof covering material

After you have laid the insulation and waterproofing material, you can begin to lay the roofing material. For it, a sheathing is installed on the roof, which is located perpendicular to the rafter beam. The lathing makes it possible to more evenly distribute the load on the structure.

When installing the sheathing, the step used depends on what material is chosen for the roof covering. For a slate sheet, the step size will be completely different from that for soft tiles.

Types of roofing materials: sand tiles, soft roofing, ceramic tiles, rubber roofing, metal tiles, wood.

When constructing a gable roof, it is possible to use a wide range of building material as finishing. Each of them has its own advantages and disadvantages, so the choice is always yours.

Let's briefly go over the main options:

. It is a good and reliable solution. Textured sheet varieties are produced that create the appearance of tiles, and there are actual metal tiles. If you choose copper covering instead of steel, the roof will last more than a hundred years. But such a design, of course, will cost you a pretty penny.
An unusual and extravagant way is to use wood covering. If the general style of the house allows, you can cover the roof with wooden shingles or spindles. Houses with a wooden gable roof will become a spectacular center of attention.
Using another type - self-leveling and soft coverings, you can design your roof in a budget and practical manner. But there is one caveat: such coating material is only possible on roofs with a suitable slope - this method is not suitable for a very steep slope.
And finally, natural tiles are an elegant, classic and prestigious covering material. It is distinguished by quality that has been proven over thousands of years of use, elegant appearance and long service life, while at the same time having a fairly decent cost.

Practical conclusions

The gable roof of a house has always been considered a universal covering material option. It’s not difficult to figure out how to properly make a gable roof of a house with your own hands, even without having the appropriate education. It is for this reason that this design has become very widely used for private buildings.

All your efforts will be justified only if all stages of the work are completed correctly. This type of roof can be used for both an attic and a cold attic.

This is roughly how the Mauerlat is fixed:

This is how the rafters are attached with pre-drilling:

This is how the sheathing is attached:

One of the simplest roofing structures is a gable roof: even a non-specialist can build it with his own hands. How to calculate the structure and build a roof frame? At one time I had to master the technique of building such roofs. I will share my experience with you.

Gable roof design

Types of rafter systems

The gable roof is one of the most ancient. It is represented by two flat slopes that meet at the top along one line. The lower edges of the slopes rest on the walls of the house, which are usually at the same level.

The end parts of the roof of gable structures are two vertical triangles-pediments. The pediment can be made of the same material as the walls, or made separately. In the second case, it is made thinner, or materials with less mass are used - this way the load on the base can be reduced.

Roof slopes can be located at different angles. If the angle is large enough, then you can build an attic space under the roof. With a slight slope, the under-roof space turns out to be low, and it is used, at best, as an attic.

A gable roof with different slopes is also possible. As a rule, it is built when it is necessary to connect two walls of different heights or when installing two slopes with different angles of inclination.

The basis of a gable roof is a rafter system, which can be of two types:

Layered rafters are made when the house has a central load-bearing wall. At its end there are racks on which the purlin is attached. It is this purlin that serves as support for the upper ends of the rafter legs, which form the slopes. Sometimes, instead of racks, a full-fledged supporting wall is erected - but this option is only suitable for houses on a massive foundation.

If the central load-bearing wall is not located in the middle of the building, then you will have to make a roof with a displaced ridge and slopes of different sizes, located at different angles.

Hanging rafters installed in the absence of a central supporting structure. The rafter legs are connected to each other without a top purlin, resting on each other (and on the ridge beam). To increase rigidity, intermediate elements are added to the structure - tightening and overlays, which prevent the rafter legs from moving apart.

The choice of rafter system is determined precisely by the design of the building itself:

there is a middle wall- we make a layered structure;
no wall- we install hanging rafters.

Calculation of rafters for a gable structure

The most important stage of the work is calculating the basic parameters of the future roof frame. There are three ways you can go here:

Use a ready-made solution, making the rafter system an exact copy of the frame of the already constructed roof. Ideal for standard houses, but it is not always possible to find a suitable option for copying.
Use an online calculator for calculating the truss structure. An option suitable for preliminary calculations and evaluation of various options. The calculators I have worked with are quite accurate, but there is a risk of not taking something into account.

Carry out the calculations yourself. To do this, you should use formulas based on SNiP 2.01.07-85 “Loads and impacts” and others regulatory documents. This option is the most difficult, but also the most reliable.

Complete independent calculation of loads is very labor-intensive. I will describe the main stages.

First we need to determine the load on the roof:

Weight load calculation- multiply the area of the slopes by specific gravity roofing This value consists of the mass of the sheathing, waterproofing, insulation and roofing material, and on average ranges from 40 to 50 kg/m2.

Snow load calculation- we multiply the standard snow load for your region by a coefficient depending on the angle of the slope. If the slopes are located at an angle of 60°, then this coefficient is taken equal to zero, if 30° - to one. Intermediate values are calculated using the formula µ = 0.033·(60 - α), where α is the slope angle.

The standard value of snow load is expressed in kg/m 3 and depends on the region. On the territory of the Russian Federation, the minimum value is 80 kg/m3, the maximum is 560 kg/m3.

Wind load calculation- we multiply the standard wind pressure in the region by the correction factor for the height of the building and by the aerodynamic coefficient (for strength it is advisable to take the minimum value - 0.8). The standard wind pressure ranges from 17 to 85 kg/m2, and the height coefficient is determined from the table below.

Height, m	Open area	Area with obstacles up to 10 m	Area with obstacles up to 20 m (urban development
Up to 5	0,75	0,5	0,4
5-10	1	0,65	0,4
10-20	1,25	0,85	0,53

We sum the obtained values to obtain the final value of the roof load.

To determine the parameters of the rafters used, we use two formulas. First we calculate the distributed load.

Qr=A·Q, Where:

Qr
A- rafter pitch, m;
Q- total load per square meter of roof, kg/m².

Then we determine the height of the section of the rafter beam. To do this, we select the optimal (as it seems to us) section width and substitute this value into the formula.

H =K·Lmax·sqrt(Qr/(B·Rben)), Where:

H- rafter section height, cm;
TO- slope coefficient. If the slope angle is less than 30°, we take it equal to 8.6, if more - 9.5;
Lmax- maximum length of the working section of the rafter, m;
Qr- load on the rafter leg, kg/m.;
B- cross-sectional width of the rafter leg, cm;
Rizg- bending resistance of wood, kg/cm² (for pine of the first grade we take it equal to 140, for the second grade - 130);
sqrt- Square root.

Calculation example:

Let's determine the parameters of the rafters for a roof with slopes of 36 degrees, with a rafter pitch of 0.28 and a length of the working part of 2.8 m. The frame is made of first-grade pine boards 5 cm wide, the total load on the roof (weight + snow + wind) is 300 kg/ m 2.

Qr=0.8·300=240 kg/m.
H= 9.5·2.8·sqrt(240/5·140) = 15.4 cm.

Since, according to calculations, we got a board larger than 150 mm, it is advisable to take thicker products. I would take parts with a cross section of 50x175 mm with guaranteed strength.

Yes, the calculation is quite complicated (and I gave an abbreviated version!). But by using it, you can check the dimensions of the supporting structures proposed to you and make sure (or not) of their reliability.

Equipment for work

Materials used

Based on the calculations, you can purchase parts for the frame, sheathing, insulation, waterproofing and roofing material. The indicative list of materials includes the following items:

Illustration	Material
	Parts for the rafter system. Roof rafters are made of timber or boards with a thickness of 40 mm, a height of 100–250 mm and a length of up to 6 m. You can also include beams or logs for support posts (when installing a layered system), a Mauerlat and a ridge beam. The ideal material for the manufacture of all these elements is well-dried pine wood of the first or second grade.
	Sheathing details. Lathing and counter-lattice are a fairly lightweight frame that is attached over the rafter system for installation of roofing material. It is made either from slats with a section of 30x30 or 20x40 mm, or from boards from 25 mm, or from plywood with a minimum of 15 mm. The choice of sheathing type is determined by the roofing material.
	Roof thermal insulation. Mounted on the underside of the slopes. Most often, slabs with a thickness of 75–150 mm based on mineral wool are used for roof insulation.
	Waterproofing. It is best to purchase special roofing membranes (Ruvitex, Tyvek and analogues) that combine waterproofness with vapor permeability. Thanks to this, condensation will not collect in the under-roof space, and the insulation will not suffer from moisture.
	Roofing material. The choice here is huge. Gable roofs can be covered with: · metal tiles; · corrugated sheets; · flexible tiles; · ceramic tiles; · slate (standard and polymer), etc.
	Additional roofing elements. This includes parts that are used for installation in areas experiencing increased operating loads. Most often, a set of additional elements includes: ridge strips; cornice strips; end strips; strips connecting to vertical surfaces; soffits, etc.
	Drainage system. Can be made of galvanized steel, polymer-coated metal or plastic. It is represented by a fastening system, gutters around the perimeter of the roof, inlet funnels and drainpipes.

In addition to the basic elements listed, we will need:

Rolled waterproofing materials (roofing felt) for laying at the point of contact of the rafter system with the walls of the building.
Fasteners (nails, screws, anchors, studs with fixing nuts, etc.).
Metal plates and brackets to strengthen the attachment points of wooden elements.
Adhesive tapes for joining rolled materials.
Impregnations for wood are antiseptic and reduce flammability.

Set of tools

To construct the rafter system, install the sheathing and lay the roofing, you will need the following tools:

Wood saw (preferably several, different ones - a miter saw for basic trimming, a circular saw for more minor works, reciprocating or hacksaw - for adjustment).
Carpenter's axes (yes, it is still more convenient to cut out grooves with a good ax).
A hammer drill with drills for the material from which the load-bearing walls are made.
Drill with a set of drills.

Screwdrivers (one per technician).
Levels (laser for setting the frame, several water levels for leveling additional elements).
Roulettes.
Plumb lines.
Hand tools - hammers, pliers, chisels, etc.
Brushes for applying moisture-proof impregnations, coating waterproofing, etc.

Since you will have to work at heights, you cannot do without several ladders, scaffolding and scaffolding for building materials.

You also need to take care of personal protective equipment, including overalls, helmets and harnesses.

Roof installation

Stage 1. Installation of the Mauerlat

We begin to install the gable roof frame by installing the support beam - the Mauerlat. To make it, we take 100x100 or 150x150 mm timber from dry pine wood.

We mount the Mauerlat according to this scheme:

Illustration	Sequencing
	Preparing the end of the wall. U wooden house The upper crown acts as a Mauerlat. For a brick or concrete building, it is advisable to pour a reinforced belt under the Mauerlat. We reinforce walls made of foam or aerated concrete with metal mortgages, after which we level the surface with mortar.
	Waterproofing. At the junction of concrete/brick and mauerlat we lay a waterproofing roll material - roofing felt or its analogues. This will protect the wood from destruction under the influence of capillary moisture.
	Laying the Mauerlat. We place the support beam on the end of the wall and carefully align it so that it lies without protrusions or distortions.
	Drilling for fasteners. We drill holes in the Mauerlat and supporting wall for installing anchors. We carry out drilling in two steps: first we go through a wooden beam with a drill, and then we make a nest in the wall fence with a hammer drill and drill. When working with structures made of porous concrete, we use special drills, since percussion drilling may lead to cracks.
	Installation of fasteners. We insert anchors with a thickness of 10 m into the holes and deepen them with hammer blows.
	Final fixation. Screw in the fastening nuts of the anchors. At the same time, the anchor sleeve expands, securely fixing it to the base.

This is not the only way to fix the Mauerlat on the wall fence. Sometimes steel studs with a thickness of 12 mm or more are embedded in brick or block masonry, and a beam with drilled holes is put on them and secured with nuts and wide washers. This method is more reliable, but also more labor-intensive - the studs need to be laid in advance, even at the stage of constructing the supporting structure.

Stage 2. Installation of racks, purlins and rafters

Instructions for installing the roof frame - rafters and additional elements - depend on the design of the rafter itself. Here I will give a description of the installation of a layered roof:

Illustration	Sequencing
	Laying the bed. We lay a beam on the central load-bearing wall, which will serve as a support for the racks and purlins. We fix the beam to the base in the same way as the Mauerlat - with mandatory reinforcement, waterproofing and fixation with anchors.
	Installation of the purlin. We connect the upper parts of the gables with a long longitudinal beam - a purlin. If the gables are a continuation of the main walls, then we support the purlin on vertical posts installed close to the gable parts.
	Installation of racks. With a pitch equal to the selected pitch of the rafters, we install vertical posts connecting the purlin and the beam. We align the racks according to the level, and be sure to fix them at the top and bottom with steel corners and secure them with self-tapping screws.
	Preparing rafter legs. We cut the boards intended for making rafters to size and, if necessary, level them with a plane. We dilute concentrated wood impregnation (antiseptic + fire retardant) and treat future rafters from all sides. Dry the treated wood thoroughly.
	Marking the rafters. We attach the rafter legs to the frame (the lower part rests on the mauerlat, the upper part on the purlin) and fix it with clamps to the temporarily stuffed bars. Using a square, mark where you need to make a cutout for attaching the rafters.
	Laying rafters. We make cuts according to the markings using a hacksaw or reciprocating saw. We put the rafter legs in place, carefully aligning them. If necessary, trim the edges of the cutout with a carpenter's axe.
	Docking at the top. We cut the upper ends of the rafter legs so that they meet with a gap of no more than 1–2 mm. We secure the rafters to the purlin with metal corners. We connect both parts with a steel plate with a thickness of at least 1.5 mm.
	Lower part fastening. We fix the base of the rafter leg on the mauerlat, drilling a diagonal hole and screwing a long self-tapping screw into it. When installing rafters made of wide boards with a small thickness, you can also use metal corners made of steel 2 mm thick.
	Installation of the bottom puffs. At the bottom of each truss we install long transverse boards, each of which should connect the left rafter, the post and the right rafter. We align the boards by level, fixing each with at least two screws. To strengthen the fastening, you can tighten the parts with bolts. We cut the protruding edges of the puffs diagonally flush with the rafters,
	Installing top ties. Exactly in the same sequence we fasten the upper tightenings. They must be located exactly under the purlin.
	Trimming the rafters. We trim the edges of the rafters, forming vertical and horizontal surfaces for installing the eaves strips. It is very important to trim all the rafters of the slope at the same level, so we carefully take all measurements before starting the operation.
	End decoration. We stuff on the vertical sections of the rafters front board, carefully leveling it. At the bottom of each rafter we cut out a small sample, after which we lay a narrow board with a thickness of 20 mm in it and fix it with self-tapping screws. This board will serve as the basis for installing droppers.

As I noted above, this is not the only design scheme. Other options for rafter systems are possible, but if you do not have experience, you should start mastering the technique with simple and proven algorithms.

Stage 3. Installation of sheathing, waterproofing and roofing work

So, the supporting structure of the gable roof is ready. Now we need to turn the frame into a full-fledged roof. This work is no longer as large-scale, but still labor-intensive.

Main stages:

Installation of waterproofing. We roll out rolls of waterproofing membrane horizontally on the rafters, fixing it directly to the rafter legs using galvanized staples. We lay the waterproofing with an overlap (from 100 to 300 mm, the greater the slope angle, the less overlap). Be sure to glue the joints of the panels.

Where ventilation and chimney pipes pass through the roof, as well as along the ridge, we install additional waterproofing.

Installation of sheathing/counter-lattice. Additionally, we fix the waterproofing material by stuffing wooden blocks with a cross-section of at least 30x30 mm along the rafter legs. On top of these bars we install a sheathing under the roofing material - slats, boards or plywood sheets. To fasten the sheathing we use wood screws.

Thermal and vapor insulation of the roof. WITH inside We lay thermal insulation mats between the rafters, which minimize energy losses through the slopes. If the price of mineral wool turns out to be prohibitive, you can also use polystyrene foam - but in this case it is advisable to take care of additional ventilation. We cover the insulation with a vapor barrier membrane, and then fix it with cross bars or sheathing made of plywood or chipboard.

Installation of the selected roofing material. We begin work from the perimeter, installing cornice and end strips. Then we install the roofing material on the slopes, taking care not to damage the waterproofing during installation. We fix the roofing sheets to the sheathing.

Installation of additional elements. We install additional roofing elements - a ridge strip that covers the junction of the slopes in the upper part, strips connecting to chimneys and ventilation, etc.

Installation of a drainage system. We fix fasteners for gutters to the front board or to the end parts of the rafters. We install gutters along the slopes with a slope towards the receiving funnels. We place funnels at the edges, from which we lower drainpipes.

Conclusion

A gable roof is just the option with which you can start mastering roofing skills. After studying my instructions and the video in this article, you will receive the minimum knowledge necessary for work, and then it’s a matter of practice. If you have any questions, ask them in the comments.

Gable roofs are most often erected during frame and low-rise construction.

Roof with two slopes- This is a triangular structure that consists of rafters, beams, and roofing.

It is quite simple: these are two inclined planes(slopes), which rest on walls located opposite each other. It also includes two triangular-shaped ends - pediments. If the building has a significant area and the roof is high enough, the under-roof space is often used as a living space. It's about about the construction of the attic.

The obvious advantages of the design include lightness, practicality and affordability in terms of price.

This is one of the most popular types of roofs. You can even install it yourself, and in a fairly short period of time.

Peculiarities

The design is almost similar to that of other pitched roofs. It includes the same elements of the rafter system; the roofing pie consists of the usual layers: vapor and waterproofing, insulation material.

Conventional materials are used as roofing: slate, metal tiles, etc.

Roofing units are arranged with special care: the ridge, the units for the passage of ventilation shafts and chimneys through the roof covering.

The specific method of installing the units and their features depend on the type of roof.

Essential elements

The main elements of a two-slope roof include:

rafters;
Mauerlat;
lathing;
load-bearing part;
horizontal ribs;
valleys;
racks;
overhangs;
waterproofing;
thermal insulation.

Rafters (or rafter legs)– one of the most important details of any roof. When constructing large buildings made of concrete and brick, a frame with concrete and metal rafter legs is installed. The length of the component elements is calculated in advance. The resulting dimensions are maintained during installation. In private house construction, wooden rafters are used, which serve as the base for the sheathing. In gable roofs, these parts are installed along the length of the building, at a specific angle. During installation, a certain distance is maintained between them.

When installing the roof, inclined, sliding and hanging rafters are used.

The sheathing is the basis for attaching the roofing covering and waterproofing layer. The boards and beams of this element are used to connect the rafters to each other - from the bottom edge of the slopes to their top. The type of roof covering determines the method of laying the sheathing: for example, when choosing bitumen shingles, the sheathing should be continuous, based on sheet material(example - waterproof plywood).

Mauerlat– is essentially a timber beam with a cross-section of 100×100 mm, 150×150 or 100×150.

This is the basis for attaching the rafter system and roof frame. The Mauerlat performs a very important function: thanks to it, the load is evenly distributed over the surfaces of the walls and protects them from destruction under the influence of external pressure. Mauerlat is laid along the perimeter of load-bearing walls, along their upper part. Although this part is also called a support beam, in reality it is most often made from a log or I-beam.

The ridge girder is located at the highest point of the gable roof. It is a timber (sometimes a board) with a cross-section of 50×200 or 50×150 mm.

With a significant span, the ridge run consists of 2 or more boards. At the same time, it is strengthened by a stand located between the bed (a beam or log laid under the ridge) and the ridge.

The struts are used to connect the racks and the purlin. The optimal location of the purlin is the space above the load-bearing (internal) wall.

Rigel– this element is a board used to fasten overlapping rafters located on opposite slopes. Its cross-section should be equal to the cross-section of the rafter legs. To increase strength, racks are installed between the beam and the crossbar.

For the overall stability of the structure and increasing the level of its resistance to external loads, additional elements are used. These are struts, braces that connect diagonal parts. They are used to strengthen the frame.

Types of roofing with two slopes

This type of roof can have two types of slopes:

smooth;
broken

Level ones are the traditional solution. They are quite simple both from the point of view of installation and from the point of view of further maintenance and repair.

Broken slopes have an unusual shape. Building them is much more difficult.

In both versions, the slopes are located at a certain angle relative to each other. The roof is a triangle closed at the top (with the help of a ridge).

The maximum efficiency (in terms of material consumption) is achieved by a roof with a slope angle in the range from 35 to 40 degrees. This angle provides optimal distribution of the total load.

The disadvantage of a roof with a specified slope is the inability to use the attic as a living space.

To increase the area of the under-roof space for the purpose of arranging an additional room, you can choose a broken variety, which is characterized by the presence of a flat upper part, while the lower half will have a sharp slope.

This design creates a fairly large attic space under the roof. With insulation and waterproofing, it can be converted into an attic. Naturally, the design of the rafter system has its own specifics.

The main types of gable roofs are:

2. Symmetrical

3. Asymmetrical

Of the three types mentioned, the first is the more traditional. Its basis is an isosceles triangle.

A symmetrical gable roof is chosen when the attic space is planned to be used as an attic, since this particular type creates a large under-roof space.

In the asymmetrical version, the skate is not located strictly in the center, but with a certain offset. This feature gives the structure a somewhat extravagant look, although the usable attic space is significantly reduced.

There are several other types of gable roofs

Looks very unusual multi-level roof. It is a broken structure, the slopes of which, unlike other options, are not connected at the ridge, but end at different levels. This feature gives the building its individuality, but the construction of the structure requires a high level of professionalism.

Gable half-hip roof- at a superficial glance it seems similar to a simple gable one, but it has its own “zest”, which is the use of beveled elements at the ends of the ridge. Its components are a gable structure made in a standard form and a trapezoidal lower part.

This feature clearly distinguishes the line between floors and allows you to get an original appearance. This type is suitable for small houses.

The half-hip is an ideal solution for regions with strong winds, since relatively low slopes protect the pediment of the building from gusts of wind and moisture.

Tilt angle

When erecting such structures, it is necessary to correctly calculate the slope angle.

The minimum angle value is calculated taking into account the characteristics of roofing materials and the influence of environmental factors.

For example, for slate the minimum angle is quite large. This is due to the following circumstance: with a “low” slate roof, the wind load increases several times, which also contributes to the penetration of moisture under the sheets. As a result, the roof becomes damp and begins to deteriorate, just like the slate itself, since moisture evaporates from under it with difficulty. If the angle of inclination is inappropriate for the material indoors Mold and mildew begin to develop, making the building dangerous to live in.

Slate, tiles - at least 22 degrees.

2. Metal tiles - 14 degrees. Moisture cannot penetrate under it, but this material is unstable in relation to strong winds, during which it can become deformed or even be torn off (a reduction in the angle leads to an increase in the ventilation gap under the roof, into which air flows penetrate completely unhindered).

3. Profiled sheets - 12 degrees. When using this coating, it is recommended to carefully coat all joints with sealant.

4. Roll materials – 5-15 degrees: the specific value is determined depending on the number of layers: when using three- or four-layer material, the angle is 5 degrees, with 1 or 2 layers the value should be within 10-15 degrees.

5. Ondulin – smallest value: 6 degrees. This coating is one of the first in terms of reliability (for structures with a small slope).

They also matter climatic features region. So, in dry climates, a gable roof can be installed at a slight angle.

With a large amount of precipitation, the value increases - up to 60 degrees: rainwater and a lot of snow do not accumulate on a steep roof.

The frequency and strength of the wind in the construction area is also important. In areas with strong winds, it is advisable to erect roofs with a slight angle of inclination to reduce the load on the structure.

Rafter structure of a gable roof and its types

There are two main requirements for a gable roof truss system: it must be strong and light: it must withstand external loads and at the same time not put too much pressure on the building.

The design of the gable roof rafter system allows the entire load to be evenly distributed along the perimeter of the building.

The lower ends of the rafters rest on the mauerlat, which is a supporting part of the structure consisting of beams.

They are secured using metal brackets or fasteners. The angle of inclination of the rafter beams determines the angle of inclination of the roof slopes.

Layered and hanging varieties of rafters are used.

These parts received the name “hanging” because of the fastening features. The edges of the rafter legs rest on the walls and roof ridge.

Layered ones are so named because of the installation method. They are used when there is a middle load-bearing wall, column or any intermediate support. Layered rafters rest on the outer (load-bearing) walls, while their middle part is located on supports.

The hanging type of rafters works in compression and bending. The expansion forces created by the rafter legs are reduced by the tie connecting the rafters.

In the layered type of rafters, the beams work only in bending, and in comparison with other roofs, the amount of costly effort is significantly lower.

The optimal choice is a combination of two types of rafters, since certain places in the structure may make it impossible to install one of the types. The combination of layered and hanging rafters increases the strength of the roof and at the same time makes it possible to use less building material.

Advantages of gable roofs

1. Simplicity and speed of the device.
2. Practicality and rationality of use. The large size of the under-roof space allows you to create a living room or a spacious attic used for household purposes. In this case, it is better to give preference to the broken variety.
3. In the attic you can install ventilation, a heating system and an air conditioning system.
4. The construction of this structure does not require special equipment or machinery.
5. When choosing the appropriate angle, precipitation does not linger on the slopes.
6. Elegant, beautiful exterior. You can realize bold architectural fantasies.
7. Cost-effectiveness - only a pitched roof is more profitable in this regard.
8. You can even carry out repairs yourself, and at minimal cost.

Flaws

1. The angle of inclination and height of the roof depend on the total area of the house. Significant dimensions require the consumption of large quantities of building materials.
2. When converting the under-roof space into an attic, the overall height of the structure must be increased, as well as the number of rafters. At the same time, they will certainly be further strengthened. As a result, financial costs increase significantly.
3. The attic must be equipped with dormer windows, which complicates the roof structure.

CONCLUSIONS:

A gable roof is simple, reliable and practical.
It consists of two slopes located at a certain angle and two triangular ends.
The slopes can be smooth or broken.
There are several types of gable roofing: broken, symmetrical, asymmetrical.
The angle of inclination is selected depending on the type of roofing material and weather conditions of a particular region.
The main detail of the entire structure is the rafter system - light and at the same time durable.
Two types of rafters are used: layered and hanging.
The main advantages of a roof with two slopes are functionality, ease of installation and reliability.
The main disadvantage: the complexity of the design and increased costs when installing an attic.

How to calculate the cost of building a gable roof, see the video clip.