Roof components. Roof composition - roof elements. How the structure of the rafter system works, which one is better to choose

The choice of roofing material and the roof structure are made during the development of the building project. It all depends on the design of the building, its construction and purpose. Roof elements, materials for the device, the choice of the type of roof depend on many factors. First of all, these are climatic and geographical conditions, architectural requirements for the structure and the degree of capital of the building. The roof design of a bathhouse or some kind of utility structure may be completely different from that of a residential building.

There are three main elements at the roof: rafters, lathing and a protective part, that is, a roof. The horizontal parts are called gutter, ridge and valley. Slopes and ribs act as inclined surfaces. Troughs are sometimes used to provide drainage at the lower edge of the ramp.

Roof structural elements

Now let's consider what the roof consists of and its protective covering - the roof.

It is known that all buildings have at least some kind of upper overlap, and civilized buildings have two types:

Attic (or top) floor. Serves to protect against cooling.
Roof. Provides protection for the entire building from precipitation, sun and wind.

Roof structural elements

The main elements of the roof:

One of the main elements is the slope - the so-called system of inclined planes, which contributes to the trouble-free removal of water sediments from the roof. We can say that it ensures its water resistance.
Ribs are raised corners that appear due to the intersection of ramps.
Endova, or groove - these are internal corners formed at the intersection of two slopes. One of the main structural elements.
Descent - this is the name of the lower part of the slope.
The drip tip is the lower part of the descent, which protects the cornice and wall from water ingress.

Behind the edge of the outer walls of the structure, there is a horizontal part of the slope, which is called the eaves overhang.
There is also a frontal overhang, which is called the inclined part of the slope.
At the edge of the slope, a gutter is necessarily made - a place for collecting melt and rainwater.

The liquid collected by the gutters is discharged and discharged downward using a drain, which is of two types:

external, in which drainpipes are installed against the outer wall of the building;
internal - downpipes are mounted inside the walls, most often used if a flat roof is installed.

However, gutters and gutters may not be used if the building height is low and the construction area is small. Water will fall from the edge of the roof directly to the ground.

Roofing elements are laid in the longitudinal or transverse direction. Roofing steel sheets are joined into a lock, and all other coatings are overlapped.

A chart to help you choose the material for the roof and the type of drainage depending on the slope of the roof.

An important parameter of the roof is the slope, which protects the roof from the accumulation of precipitation, especially snow. It is expressed mainly in degrees, but in the drawings you can also find a bias in percent. The material for the coating and the method of removing moisture from the roof depend on this indicator.

Geometric roof shapes

Surely for some uninitiated people in construction it will be a surprise how many different geometric shapes of the roof exist. Of course, each of them is used for a certain type of buildings:

Shed roof. It is used for fairly simple buildings that do not have drainpipes and snow dropping. It is also optimal for those buildings that adjoin the longitudinal side of a larger building. Indispensable for auxiliary buildings: baths, toilets, gazebos, etc. The simplest type of roof, which does not require a large amount of material, but at the same time one of the most durable.
Gable, or gable. This is a construction of two inclined slopes. The triangular space between the ramps is called gables or gables. One of the most popular types of roofs used in the construction of houses, cottages and buildings with a small number of floors.

Roofs are different, as this figure shows. There is no three-pitched roof. The conical gable design looks the most original

Four-slope. Subdivided into hip and hip. It is mainly used in rural and suburban construction.
Dome. Serves to overlap buildings. One of the oldest types of roofs. It is often used in the construction of hotels or pavilions.
Mansard room. A kind of gable roof.
Vaulted. It is used to cover industrial or public buildings of a rectangular plan.
Conical. Indispensable in the construction of round buildings.
Pyramidal. "Serves" buildings of a square or polygonal plan.

As you can see, depending on the shape and purpose of the building, one or another type of roof is used. For a toilet or a bath, using a four-pitched structure is complete stupidity, just as for multi-storey buildings a pitched roof is an unsuitable option.

In addition to their shape, roofs are also divided according to their design. According to this indicator, they can be attic and attic. Attic (split) roofs, depending on the type of building, can be insulated or cold. In the combined (attic) roofs, the load-bearing elements cover the upper floor of the building. Roofs without attic are built without ventilation or with full or partial ventilation.

The difference between an attic and an attic roof. In roofs without an attic, the load-bearing wall takes over the load.

As we have already mentioned, the choice of the shape of the roof depends on the architectural concept, the type of roofing material, etc. A lot is decided by the slope of the slopes and the features of the supporting structure. Climatic conditions cannot be neglected. In warm areas, roofs with a slight slope are popular, and in snowy conditions, with a steep slope and a small overhang so that snowfall does not linger on the roof. In strong wind conditions, the structure should be gently sloping to reduce windage.

Rafters

As the base of any roof, rafters made of wooden planks or beams are used. This is a supporting structure that takes the weight of the roof on itself, so it is always made of high quality wood, without cracks and rot. The material for the manufacture of rafters is coniferous boards or beams. They must be perfectly dry and contain a minimum of knots. The use of logs is acceptable, but they are much heavier.

The rafters are supported by the Mauerlat. This is a bar with a cross section of at least 10x10 cm or a log, necessarily hewn from the bottom side. This element is also designed to distribute the load on the load-bearing walls evenly. The upper crown of a log house can be used as a mauerlat for the construction of cobbled and chopped buildings.

Diagram of rafters for a gable roof. Mauerlat as a support is required.

The cross-section of the rafters is calculated additionally, and it depends on several indicators: the load created by the weight of the roof and snowfall, the pitch of the rafters, the size of the span and the slope of the roof. According to the method of installation, the rafters are divided into two types: layered and hanging. The first ones are installed obliquely on supports, which are external walls (at a gable roof) or internal with external (in a gable). Hanging rafters only support the walls of the building. They are installed in those buildings where there are no additional supports and internal load-bearing walls.

Sheathing is used as a basis for maintaining and laying the roof. It can be solid, but most often it is done with some step, which depends on the material. The main requirements for the manufacture of the base:

all parts must be tightly fixed to the supporting structure;
joints above the rafters must be staggered.

The stepped lathing is used when the covering is made of asbestos-cement sheets, roof tiles or sheet steel.

Solid flooring can also be used as a base, but it is only suitable for roll material or flat asbestos-cement tiles. The distance between the boards or beams should be the same over the entire surface.

The lathing is made from edged boards. Depending on the type of the intended roof and the roof structure, it can be solid or discharged.

General conclusions

The roofing device, although it seems complicated, contains elements, each of which performs its own functions. Much depends on the structure of the entire roof, which is developed during the design of the building or planning the renovation.

The roof of your house will be reliable and durable only when all the components are correctly and correctly installed: roofing, ribs, ridges, gutters, abutments to pipes and other components. It is better to buy a roof in a complete set, which has all the necessary materials and accessories, and from one manufacturer.

A complex roof with a fancy design

Private architects or design bureaus should be engaged in the design of buildings, since only they have the necessary permission for this. The finished house project contains the roof plan, all the nodes and details of the roof structure. Direct construction should be trusted only by professionals who will perform high-quality installation and provide a guarantee for the work performed.

The installation of a gable roof is actively practiced in private construction, since this is the simplest and most affordable way to build a reliable roof at home. This article describes the main stages of installation, which can be performed independently, with a certain skill of roofing.

Functional features of a gable roof

The gable type roof structure consists of load-bearing elements (mauerlat, rafter system) and enclosing (roof). A gable roof (gable) has two roof surfaces located at a certain slope to the outer walls of the building, which provides a natural drain of moisture from melted snow and rainwater. According to SNiP, the angle of inclination of such a roof should be more than 5 °.

The choice of the slope angle of the roof slopes is influenced by:

type of topcoat material;
architectural features of the structure;
climatic conditions of the construction area.

The construction of a gable roof with a high angle of inclination is usually practiced under the condition of using relatively light roofing materials and in regions without a large wind load, since the pitched roof of the building is a sail. In addition, a steep pitched roof is a practical option for areas with a lot of rainfall - it quickly and successfully removes rain moisture from it, and the accumulated snow slides down under its own weight.

Gentle roofs experience minimal wind load, but are very sensitive to snow. To avoid the destruction of the structure under the load from snow masses, the roof should be regularly cleaned in winter.

In private construction, gable roofs with an angle of inclination from 35 to 60 ° are most often erected.... This is the best option in terms of the ratio of the roof's resistance to atmospheric loads and reasonable costs for materials for installing the rafter system, as well as arranging the roofing pie.

The installation of a gable roof begins with the installation of a Mauerlat or floor beams, depending on the type of rafter system selected. Mauerlat acts as the foundation for the roof structure. It is he who allows you to evenly distribute the load (the weight of the rafter system itself, snow and wind loads, the weight of people serving the roof), transferring it to the building structures of the structure.

Mauerlat is a coniferous timber with a section of 150 × 150 mm (most often). When erecting a gable roof, it is mounted on two parallel walls. If the project provides for the installation of layered rafters with a ridge run on supports, then the Mauerlat beam should also be laid on the middle bearing wall.

During the construction of wooden houses, the Mauerlat is not mounted - it is an element for laying on building structures made of bricks, foam concrete blocks and other material. On small buildings, the Mauerlat can be attached to the walls using forged wire embedded in the masonry. When building a house, it is practiced to arrange a monolithic beam with installed fasteners.

To complete the beam, a wooden formwork is mounted in the upper part of the walls, metal reinforcement rods are attached (at least 2 pairs of parallel lines, one above the other). With the help of wire, studs or anchors are attached to the reinforcement. It is important to install them in increments of no more than 1 meter, strictly vertically. The prepared formwork is poured with concrete.

The length of a stud with a diameter of about 14 mm is determined based on the thickness of the monolithic beam, the thickness of the Mauerlat bar plus one or two layers of waterproofing made of roofing material. At the same time, when laying the Mauerlat, the pins should be at least 3 cm above its surface in order to be able to fix the timber using nuts with wide washers.

When preparing for the device of a monolithic beam, it is necessary to determine in advance the installation location of the fasteners for the Mauerlat. The beam can be laid strictly along the axis of the beam or with a shift towards the inner or outer side of the wall. To secure the Mauerlat, holes for the studs should be made.

Mauerlat is mounted at least 5 cm from the outer edge of the wall.

If the roof frame is planned to be made of metal elements, a channel or I-beam metal profile can act as a Mauerlat.

The rafter system with hanging rafters can be installed without a Mauerlat. In this case, the lower parts of the rafter legs are attached to the floor beam, which is laid across the walls. The beam acts as a tightening and provides the rigidity of the truss. The construction of a gable roof according to this principle is usually used when erecting buildings with a small span, most often from a bar or log. It is not recommended to mount the support beams on walls lined with piece materials, since a point load can destroy building structures.

Gable roof rafter system

The rafter system includes the rafters themselves (rafter legs), as well as a number of other elements, the installation of which is necessary to ensure the rigidity of the structure:

crossbars;
runs (including ridge);
racks;
lie down;
spacers;
struts, etc.

Rafter systems can be mounted in wood or metal, or a combination of both materials.

Designing a rafter system is an important stage in preparing for construction. Errors in the design can lead to the fact that the roof collapses over time under the influence of operational loads. On the other hand, having designed an excessive margin of safety for the roof frame, you will have to spend extra money on its construction.

The design of the gable roof rafter system is based on the most stable and rigid geometric figure - a triangle. When installing truss systems of a simple design, the rafters are made of a bar with a cross section of 40 × 150 mm to 100 × 250 mm. The choice of a specific value depends on the following factors:

installation step;
rafter leg length;
calculated value of the load.

In turn, the type of roofing cake affects the step of installing the rafter legs - if it is supposed to install a warm roof, then this parameter is selected taking into account the width of the roll or sheet insulation.

Types of truss structures

Considering how to build a gable roof, you need to pay attention to the specifics of the construction of rafter systems of various designs - with hanging and layered rafters. The rafter legs are the main element of the gable roof frame. They function as a support for the roofing cake. Hanging rafters do not have intermediate supports, and only rest on the walls of the building. Inclined rafters have additional support points.

A truss, assembled from two rafter legs and a lower tightening or an upper crossbar, is a structure that works in compression and bending. The bursting effect of the angled rafter legs is compensated by the horizontal lintel. The higher the tightening is mounted, the stronger and more rigid one must be fixed. This design allows even wide spans to be bridged..

The top of the hanging rafters can be attached in a variety of ways. The rigid attachment of the upper ends of the rafter legs is reinforced with overhead elements made of wood or metal. When attaching the rafter legs to the Mauerlat, a cutout (saddle) is made on the bottom of the rafter, after which the element is rigidly fixed with nails and wire twist. If the rafter legs are installed on a floor beam, a stop is cut in the beam to prevent displacement, and in the rafter leg, a single or double tooth. Installation is carried out using various metal fasteners.

In the Mauerlat beam, the cut is not made so as not to weaken the bearing capacity of the roof support.

The roof frame with layered rafters is installed if there is a middle load-bearing wall or columnar supports in the building. The span between the supports should be no more than 6.5-7 meters. The width of the slab can be increased by installing additional supports: up to 11.5-12 meters with one additional support and up to 15-15.5 meters with two. To increase the rigidity of the rafter system and expand the opening between the supports, you should install a rack with struts under the ridge girder. The load on the roof is transferred by the middle part of the rafters to the internal supports, and by the lower ends to the external walls.

Installation of a rafter system with layered rafters is somewhat easier than assembling and installing rafter trusses. After installing the ridge girder on the gables of the building or special racks, the rafters are attached to it with their upper part.

In some cases, it is advisable to use both layered and hanging rafters when installing the roof frame.

The construction of the truss system must be carried out using quality material to ensure the durability of the roof. The lumber must have a strict geometric shape, wood defects are not allowed. To prevent wooden elements from warping after installation, the material must be well dried.... Before installation, it is required to process the prepared parts with a fire retardant agent.

Roofing cake device

The question of how to properly build a gable roof, in particular, is associated with the competent implementation of the roofing pie. The functionality of the structure depends on this, its ability to provide reliable protection of the building from external influences.

When installing the roof, it is important to observe the projected lathing pitch, having previously installed the counter-lattice to create a ventilation gap for the roofing cake. To ensure the necessary air circulation in the under-roof space, a ventilation box is installed in the ridge part, ventilation holes are provided in the filing of the eaves.

Particular attention is paid to reliable waterproofing of the roof, otherwise the moisture condensed on the wooden elements can cause rotting of the structures. If the attic of a gable roof is supposed to be used as a living space, it is required to provide for reliable insulation and vapor barrier of the roof.

To ensure the strength and durability of a gable roof, you should carefully approach the development of the project, the choice of materials and adherence to the technology of work.

Installation of a gable roof, how to build correctly, construction

We are learning to do the installation of a gable roof with our own hands. In the article, you will learn how to properly build a gable roof and how its construction begins.

How the structure of the rafter system works, which one is better to choose

The roof structure is considered the most difficult unit of a residential building in terms of design and installation. Wind, precipitation and cold fall on the roof, therefore, it must be airtight and durable to create a comfortable living environment. The main part of the roof is the rafter system, with the help of which the shape of the structure is created, the optimal angle of inclination is set and the waterproofing material is attached. The number of elements of the rafter system, as well as their location, is determined by the configuration of the roof.

The purpose of the rafter system

The rafter system is a certain number of supporting elements that create the geometry of the roof and frame, which gives the roof structure rigidity and the desired slope. The main parameters of the constituent parts of the rafter system and their location are determined taking into account permanent and temporary loads.

In general, the rafter system has the following tasks:

Creation of the shape and angle of inclination. The location of the rafter legs determines the shape of the roof, hence the number of tongs and ramps. In addition, with the help of these elements, the angle of inclination of the slopes is formed for the rapid disappearance of snow, melt and rain water.
Uniform distribution of the roof load on the load-bearing walls of the house. The rafters of the system are interconnected and distributed in the structure so that the weight of the roof covering and the snow mass is evenly transferred to the frame of the building, while there is no distortion or deformation of the structure.
Creation of conditions for normal ventilation and protection from moisture. The roof frame is assembled in such a way that air circulates freely in the under-roof space, and the material itself is reliably protected from condensation accumulation.

In addition, the rafter system serves as the basis on which the waterproofing material and the lathing for the finish coat are attached.

With the correct drawing up of the rafter system, the roof will be reliable and durable and will last a long time. According to experts, a high-quality frame is of greater importance, therefore, there is no need to save at this stage. Therefore, it is best to entrust the drafting of the roof project and its installation to professional craftsmen.

Features of choice

The rafter system of a building consists of a certain set of additional elements and has its own level of installation complexity. The number of auxiliary parts is determined taking into account the loads from the roofing material and some environmental factors.

When choosing the type of rafter system, you should pay attention to the following factors:

Features of the climate of the area where construction is planned. Protecting the roof from destruction during snowfalls or heavy rainfall is possible only if the average annual amount of precipitation is correctly calculated. The best roof option in snowy regions is a steep slope.
Wind load. The optimal design option is selected based on the wind rose at the construction site and the average speed of air gusts. In windy regions, the slopes are made flatter.
Use of attic space. The creation of a living space under the roof is of great importance when choosing the shape of the rafter system.
Topcoat used. In order for the roofing to perform its functions as much as possible, you need to choose the correct angle of inclination of the slope, taking into account the shape and method of fastening the material.
Financial opportunities. Installation of a roof structure requires large financial investments, therefore, the type of roof should be chosen in accordance with the construction budget.

Types of rafters

No roof is complete without a rafter system. The quality of the roof structure largely depends on what is included in the roof rafter system. The vertical supports, horizontal braces and rafter legs provide a secure base and support for the roof covering. For the manufacture of the frame, it is necessary to use light materials that do not load the box at home. They must be strong, with a high load-bearing capacity and good resistance to negative natural phenomena.

The most common options are:

Wooden frame... Such a rafter system has low weight and good strength, and the natural origin of the material ensures safety for residents and the environment. The frame is assembled from bars with a section of 10 * 10 cm or 15 * 15 cm or boards 5 * 15 cm. Among the shortcomings of wood, one can note poor resistance to moisture. In addition, the large length of the products contributes to their bending under their own weight.
Metal rafter system it is distinguished by its high cost, but when installing a large area of slopes and using heavy roofing materials, it becomes indispensable. The metal profile has a high bearing capacity, which makes it possible to increase the distance between structural elements without reducing the strength characteristics. The metal's only drawback is its poor corrosion resistance. To solve the problem in this case, metals are used that are resistant to this phenomenon.

Structural elements and details

All elements of the rafter system are interconnected. Thanks to this, the structure has the rigidity and the necessary strength, and the weight from the roofing is evenly distributed on the load-bearing walls and partitions. The presence of certain structural elements, their section and location depends on the selected roofing material, the angle of inclination of the slopes and the purpose of the attic space.

The main parts of the rafter system are as follows:

Mauerlat... This element is a truss, located on the top row or crown of the load-bearing walls of the house. For its manufacture, coniferous wood is used, which is distinguished by its hardness and strength. The Mauerlat is fastened with metal studs or anchor bolts.
Sill... This element, made of timber, is located on the internal load-bearing partitions. The bed serves as a support for the racks, which are necessary to support the skate.
Racks- these are supports located vertically along the entire length of the bed and supporting the ridge or the central part of the truss.
Rafters are located at a certain angle to the base of the roof. The support for the rafter legs is a Mauerlat and a ridge bar.
Crossbar and tightening- the necessary horizontal elements for the paired connection of the rafter legs. The crossbar tightens the rafters directly under the ridge girder, the tightenings are slightly lower.
Braces... These elements are positioned at an angle to the rafter leg to prevent sagging. The upper edge of the brace rests against the rafter, the lower edge against the rack or tightening.

For the construction of a simple structure of the rafter system, it is enough to use a Mauerlat, ridge beam and rafters. The increasing level of complexity leads to the use of additional elements that make the structure more robust and resistant to deflection.

Types of rafter system

The architectural features of the structure have a great influence on the configuration of the roof, since the load from the roof structure must be evenly distributed between all load-bearing walls and partitions.

In this regard, the following types of rafter system are distinguished:

Rafter roof system... In this design, the roof frame rests directly on the load-bearing walls outside and inside the structure. Supports on internal load-bearing walls are required to support the ridge girder. Inclined rafters allow covering a large area while maintaining strength characteristics.
Hanging rafter system assumes the support of the rafter legs only on the Mauerlat. In the upper part, the rafters abut against each other without a ridge. These types of rafters are used when overlapping structures that do not have internal load-bearing partitions. The truss in this case has the shape of an equilateral triangle, therefore, stabilizing elements are not required.

The result of the choice of types of rafter system and their structural elements can be a simple roof with one or two slopes, or a more complex one - hip and hip.

The structure of the rafter system: types of rafters, structural elements, roof details, what is included, parts

Arrangement and installation of a wooden truss system

The roof of the building protects it from cold weather, rain and wind. It is as important as the exterior walls and foundations. The rafter system is the supporting structure of the roof. She takes over all the loads: from structures, from snow and wind. In order to avoid problems during operation, the structure of the roof of the house must be strong and reliable. Do-it-yourself installation of the rafter system should be done only after careful preparation and study of all the necessary information.

Roof and roof

Before you start building the roof of a private house, you need to distinguish between two concepts. Non-professionals are often confused, but builders clearly separate the definitions of roof and roofing. The roof is the entire structure that separates the building from the street from above. The roof structure of a private house includes rafters, all other load-bearing elements, thermal insulation material, roofing.

Rafters - roof supporting structures

The roof is the top of the roof. She is also a roof covering... Roofing device requires careful selection of material. After all, the reliability of waterproofing and the comfort of living will depend on it.

System Requirements

To properly mount the rafter system with your own hands, you must take into account a certain set of rules. Without taking them into account, the structure will not be able to effectively resist negative influences from the outside.

First of all, it is worth considering the strength. All elements must withstand the load without destruction... The device of the roof rafter system involves a preliminary calculation of the supporting structures for the first limiting state. It is he who checks the elements of the rafter system for strength.

The rafter system must be strong and rigid

The second requirement is rigidity... The maximum deflection is taken into account here. The structure of the roof of a wooden house or any other should not sag too much. Permissible deformations in the middle of the span are equal to the length of this span, divided by 200. Before starting construction, the structure of the rafter system must be calculated according to the second group of limiting states - for rigidity.

Do-it-yourself roof rafters are made taking into account that the structure has a low weight. Otherwise, the load on the walls and foundations increases greatly. It is for this reason that wood has become widespread as the main material. The wooden rafter system has sufficient strength, but weighs relatively little. Attention should be paid not only to the roof structure, but also to choose the roofing material correctly. It shouldn't be too heavy. Ceramic tiles have lost their popularity not only because of the cost, but also because the roof of the house, its walls and foundations must be reinforced under it.

The weight of the roofing material for a wooden truss structure should not be too large

Special requirements are placed on the quality of the material. The manufacture of wooden elements should only be carried out from good raw materials. Consider the following recommendations:

For the main elements, 1 or 2 grade wood is used. Grade 3 can only be used for lathing and other small parts.
The rafter structures of pitched roofs are recommended to be made of conifers. They are more resistant to decay and other troubles because they contain resin. With the same cross-section, the allowable span for hardwood will be less.
Before starting work, all elements must be treated with an antiseptic. This stage of preparation allows you to prevent many troubles in the future. Also, if you wish, you can treat the wood with fire retardants. This will increase the fire resistance.
It is better to buy timber from the northern regions, which is harvested in the winter. It is this material that has the highest quality.

Parts of the structure

The rafter system diagram includes many elements. To understand the drawings and correctly perceive the information, you need to know at least the main ones. So what does a roof consist of?

Ridge, cornice and ramps - the main part of the roof

First of all, these are the ridge, the cornice and the slopes. These items are the main parts... The ridge is the uppermost part of the structure. The cornice or overhang is the lower one. Slopes are inclined surfaces that are located between the ridge and the cornice.

The construction of a rafter system requires knowledge of the supporting elements. These include:

Mauerlat - a timber that is laid along the edge of the walls of the building... The Mauerlat is needed to evenly transfer the load from the rafter legs, which are point-based. Usually, for its manufacture, a beam with dimensions of 150x150 mm or 200x200 mm (for large buildings) is used.
Rafter legs are inclined beams that transfer the load from the roof's own weight, snow and wind to the Mauerlat... These beams are usually installed from ridge to eaves. But when erecting a hip roof, elements appear that have only one of the indicated points. They are supported on a ridge or cornice. Such details are called worms. They usually have the same cross-section as the rafters. In fact, the rafters are rafter legs cut off on one side.
Run - a beam on which the roof elements rest... The purlin can be installed under the posts. Another option is a ridge girder (crossbar). The rafters rest on it at the top point. The cross-section of the run depends on its span, usually 200x200 mm is taken.
Slant legs are only needed for hip roofs... They are diagonal rafters supported by the Mauerlat at the corners. The section is taken to be enlarged, usually 150x200 or 100x200 mm.
The construction of a wooden roof assumes the presence of puffs, struts and struts... They are designed to reduce stress on the main components. When building a house with your own hands, it is important to remember that the racks cannot be supported on the floor span. Installation is only possible on underlying walls or on purlins thrown between walls. It is possible to mount such elements on the floor only if it is designed for such a load and is reinforced in the desired area.
The lathing is needed in order to make the base under the cover... For metal tiles and standing seam roofing, the sheathing can be thinned from boards with a thickness of 32-40 mm. For bituminous shingles, you need a solid base of boards 25-32 mm thick or moisture-resistant plywood.
In order to make the overhang of the cornice, filly are installed... They become an extension of the rafters. The filly is fastened to the rafters for a length of at least 1 m. The section of the element is usually taken 50x100 mm.

Bearing elements of the hip roof

Another element of the rafter system is the truss. It is a one-piece structure, which consists of rafters, braces, struts and struts, rigidly connected to each other. The truss has a triangular shape, and inside it is divided into several smaller triangles, which provides it with good stability.

Roof shapes

Pitched roofs come in a variety of shapes. It is worth highlighting here:

single-slope;
gable;
hip (hip and hip);
broken lines.

The most common gable and gable hip roofs

The most common option is a gable or four-pitched hip roof.... The first requires the device of gables. Broken lines are relevant when building an attic. First, the rafters go at a steep angle, and then at a smaller one. This technology allows you to raise the ceiling of the attic room. We also recommend reading about the half-hip roof rafter system.

Types of rafters

There are two designs:

with layered rafters;
with hanging rafters.

The device of the roof of a wooden house is possible only with the use of the former. This is due to two rules:

hanging rafters must be rigidly attached to the Mauerlat;
in a wooden house, the rafters must be hinged to the Mauerlat.

These two statements contradict each other, therefore, the truss system of a wooden house can contain only layered elements.

Only layered rafters are mounted in a wooden house.

Inclined beams are elements that rest on the Mauerlat at the bottom point and on the ridge girder at the top... This allows you to reduce the horizontal spacing that acts on the walls when the rafters try to part and take a horizontal position. Elements can be reinforced with uprights or struts. In this case, contractions can be placed through one pair of legs.

Hanging tanks rest only at the lowest point on the Mauerlat... At the top, they just bump into each other. To ensure that the system of wooden elements does not disperse, it is imperative that puffs are made. Better to install them on each pair of legs. This option is characterized by a strong expansion effect on the outer walls, but it allows you to get more free space inside the attic.

Connections

Before you make a rafter system with your own hands, you need to carefully study the nodes. It is not worth saving time or money to build your home. Only in this case, the result will delight for many years.

The main joints of the rafters

The attachment points for the roof truss system, which deserve special attention, are represented by the following:

fastening the Mauerlat to the wall;
fastening the rafters to the Mauerlat;
fastening the rafters at the top point;
splicing rafters along the length.

Mauerlat to the wall

This knot can be done in several ways. The choice largely depends on the material of the wall. Building a building from brick, block or concrete allows the following methods to be used:

on the wire;
on staples;
on hairpins;
on an anchor with a monolithic belt device along the edge of the wall.

The connection of the Mauerlat to the wall during the construction of brick buildings is carried out using anchors

In wooden construction, the upper crown of the wall acts as a Mauerlat. It is connected to the previous ones on the dowel. In a frame house, the Mauerlat is the upper trim of the walls. It is fixed on the frame racks by means of a cut and metal corners with holes for self-tapping screws. Read more about attaching the Mauerlat to the wall.

Rafters to Mauerlat

Fasteners are carried out in two ways:

rigid for brick, concrete or concrete block buildings;
articulated for wooden houses.

Rigid mount can be with or without a cut. The cut is recommended to be done on the rafters, and not on the Mauerlat, as this weakens it. In both cases, the leg is rigidly fixed with nails, screws, staples or metal corners.

With rigid fastening, the cut is best done on the rafters and fixing the structure with fasteners

For a hinged mount, a special part is used - a slide... They allow the beam to mix without obstacles during the shrinkage of the building walls.

The articulated connection allows the beam to be displaced

Additionally, the rafter legs are attached to the wall. This is to prevent the roof from being blown off by the wind. For fastening, a twist of two wires with a diameter of 4 mm is used, fixed to the wall on an anchor or a ruff. In a wooden house, twisting can be replaced with staples. Fastening is carried out on each beam or through one.

At skate level

Inserted elements rest on a ridge girder with a cut... Additionally, an overlay is made from a board on both sides. An overlay is also needed for hanging elements. It can be wooden or metal with holes for self-tapping screws.

The ridge girder and rafters are connected using a cut

Splicing rafters

There are several methods for splicing roof rafters with your own hands. The choice between them largely depends on the experience of the master. The splice is located at a distance of 0.15 of the span length from the support... In this case, not only the ridge girder and the Mauerlat, but also the struts and racks are considered as supports.

Splice rafters lengthwise

There are five ways:

To build a high-quality roof, you need to carefully study the technology, choose the right type of rafters and methods of connecting elements in important nodes. This is especially important when a do-it-yourself rafter system is being built.

Roof truss system of a private house: device and installation

How to make a wooden roof of a private house correctly. Rafter system: structural elements, rafters, attachment points and do-it-yourself installation.

Types of gable roof truss system: for small and large houses

At the heart of each roof is a large number of beams, rafters, uprights and purlins, which are collectively referred to as the rafter system. Over the centuries-old history of species and methods of its organization, a lot has accumulated, and each has its own characteristics in the construction of nodes and cuts. We will talk in more detail about what the rafter system of a gable roof can be and how the rafters and other elements of the system should be attached in this case.

The structure of the gable roof truss system

In section, the gable roof is a triangle. It consists of two rectangular inclined planes. These two planes are connected at the highest point into a single system by a ridge bar (run).

Gable roof scheme

Now about the components of the system and their purpose:

Mauerlat - a beam that connects the roof and walls of the building, serves as a support for the rafter legs and other elements of the system.
Rafter legs - they form the inclined planes of the roof and are the support for the sheathing under the roofing material.
Ridge girder (bead or ridge) - unites two roof planes.
Tightening is a transverse piece that connects opposing rafter legs. Serves to increase the rigidity of the structure and compensate for bursting loads.
Beds are bars located along the Mauerlat. Redistribute the load from the roof.
Side Girders - Supports the rafter legs.
Racks - transfer the load from the girders to the benches.

Filly may still be present in the system. These are boards that lengthen the rafter legs to form an overhang. The fact is that to protect the walls and foundations of the house from precipitation, it is desirable that the roof ends as far as possible from the walls. To do this, you can take long rafter legs. But the standard length of lumber of 6 meters is often not enough for this. Ordering a non-standard is very expensive. Therefore, the rafters are simply grown, and the boards with which they do it are called "filly".

There are quite a few constructions of truss systems. First of all, they are divided into two groups - with layered and hanging rafters.

The difference in the design of the layered and hanging rafters

With hanging rafters

These are systems in which the rafter legs rest only on the outer walls without intermediate supports (load-bearing walls). For gable roofs, the maximum span is 9 meters. When installing a vertical support and a system of struts, it can be increased up to 14 meters.

The hanging type of the gable roof rafter system is good in that in most cases there is no need to install a Mauerlat, and this makes the installation of rafter legs easier: you do not need to make cuts, it is enough to mow the boards. To connect the walls and rafters, a lining is used - a wide board, which is attached to studs, nails, bolts, and crossbars. With such a structure, most of the bursting loads are compensated, the impact on the walls is directed vertically downward.

Types of rafter systems with hanging rafters for different spans between load-bearing walls

Gable roof rafter system for small houses

There is a cheap version of the rafter system when it is a triangle (photo below). Such a structure is possible if the distance between the outer walls is no more than 6 meters. For such a rafter system, you can not do the calculation by the angle of inclination: the ridge must be raised above the tightening to a height of at least 1/6 of the span length.

But with this construction, the rafters experience significant bending loads. To compensate for them, either rafters of a larger section are taken or the cut of the ridge part is made so as to partially neutralize them. To give greater rigidity in the upper part, wooden or metal strips are nailed on both sides, which securely fasten the top of the triangle (also see not the picture).

The photo also shows how to extend the rafter legs to create a roof overhang. A cut is made, which should go beyond the line drawn from the inner wall upwards. This is necessary in order to displace the notch and reduce the likelihood of the rafter breaking.

Ridge knot and fastening of rafter legs to the underlay board with a simple system version

For mansard roofs

The option with the installation of a crossbar is used when organizing a dwelling under the roof - an attic. In this case, it is the basis for filing the ceiling of the room below. For reliable operation of this type of system, the crossbar cut must be non-hinged (rigid). The best option is semi-rotten (see the picture below). Otherwise, the roof will become unstable to loads.

Raised Gable Roof Rafter System and Girder Cutting Assembly

Please note that a Mauerlat is present in this scheme, and the rafter legs should extend beyond the walls to increase the stability of the structure. To fix them and dock with the Mauerlat, a cut is made in the form of a triangle. In this case, with an uneven load on the slopes, the roof will be more stable.

With this scheme, almost all the load falls on the rafters, therefore they must be taken of a larger section. Sometimes the raised tie is reinforced with a suspension bracket. This is to prevent it from bending if it supports the ceiling sheathing materials. If the puff is short, it can be secured in the center on both sides with boards nailed to the nails. With a significant load and length of such insurance, there may be several. In this case, too, planks and nails are enough.

For large houses

With a significant distance between the two outer walls, a headstock and struts are installed. This design has high rigidity, since the loads are compensated.

Gable roof rafter system for a large span and cuttings for ridge and rafters

With such a long span (up to 14 meters), it is difficult and expensive to make an integral tightening, therefore it is made of two beams. It is connected with a straight or oblique cut (figure below).

Straight and oblique notch for tightening connection

For a secure fit, the joint is reinforced with a bolted steel plate. Its dimensions should be larger than the dimensions of the cut - the extreme bolts are screwed into solid wood at a distance of at least 5 cm from the edge of the cut.

In order for the circuit to work normally, it is necessary to make the braces correctly. They transmit and distribute part of the load from the rafter legs to the tightening and ensure the rigidity of the structure. Metal pads are used to reinforce the connections.

Attaching the struts for the truss system with hanging rafters

When assembling a gable roof with hanging rafters, the cross-section of lumber is always larger than in systems with layered rafters: there are fewer load transfer points, therefore, each element has a large load.

With layered rafters

In gable roofs with layered rafters, their ends rest on the walls, and in the middle part they rest on load-bearing walls or columns. Some schemes burst the walls, some don't. In any case, the presence of a Mauerlat is required.

The simplest version of layered rafters

Spreader-free schemes and cutting units

Houses made of logs or beams do not respond well to spacer loads. For them, they are critical: the wall can fall apart. For wooden houses, the rafter system of a gable roof must be non-thrustable. Let's talk about the types of such systems in more detail.

The simplest spreader-free diagram of the rafter system is shown in the photo below. In it, the rafter leg rests on the Mauerlat. In this version, it works for bending without bursting the wall.

Simple spreadless gable roof system with layered rafters

Pay attention to the options for attaching the rafter legs to the Mauerlat. In the first, the support area is usually beveled, while its length is no more than the cross-section of the beam. The depth of the cut is no more than 0.25 of its height.

The top of the rafter legs is laid on the ridge beam, without fastening it to the opposite rafter. The structure turns out to be two single-pitched roofs, which in the upper part adjoin (but do not connect) one to the other.

The version with the rafter legs fastened in the ridge part is much easier to assemble. They almost never give space to the walls.

Option for attaching rafters without spacer on the walls

For this scheme to work, the rafter legs at the bottom are attached using a movable joint. To fix the rafter leg to the Mauerlat, one nail is hammered from above or a flexible steel plate is placed from below. See the photo for the options for attaching the rafter legs to the ridge girder.

If the roofing material is planned to be used heavy, it is necessary to increase the bearing capacity. This is achieved by increasing the cross-section of the elements of the rafter system and strengthening the ridge assembly. It is shown in the photo below.

Reinforcement of the ridge knot for heavy roofing material or with significant snow loads

All of the above gable roof schemes are stable in the presence of uniform loads. But in practice, this practically does not happen. There are two ways to prevent the roof from sliding towards a higher load: by installing a scrum at a height of about 2 meters or with struts.

Variants of rafter systems with scrapes

The installation of scrapes increases the reliability of the structure. In order for it to work normally, at the points of its intersection with the drains, you need to fasten it to them with nails. The cross-section of the timber for the fight is used the same as for the rafters.

Diagrams of gable roof truss systems with skirmishes

Attached to the rafter legs with bots or nails. Can be installed on one or two sides. See the figure below for attaching the scrum to the rafters and ridge girder.

Attaching the scrum to the rafter legs and ridge bar

In order for the system to be rigid and not "crawl" even under emergency loads, it is sufficient in this version to provide a rigid fastening of the ridge bar. In the absence of the possibility of its displacement horizontally, the roof will withstand even significant loads.

Systems of layered rafters with struts

In these options, for greater rigidity, rafter legs are added, which are also called struts. They are installed at an angle of 45 ° to the horizon. Their installation allows you to increase the length of the span (up to 14 meters) or reduce the cross-section of the beams (rafters).

The brace is simply placed at the required angle to the beams and nailed from the sides and bottom. An important requirement: the brace must be cut accurately and fit snugly to the uprights and rafter leg, excluding the possibility of its deflection.

Systems with rafter legs. Above the spacer system, from the bottom - non-spacer. The nodes of the correct felling for each are located next to each other. Below - possible schemes for attaching the strut

But not all houses have the middle load-bearing wall in the middle. In this case, it is possible to install struts with a tilt angle relative to the horizon of 45-53 °.

Off-center vertical purlins rafter system

Strut systems are necessary if significant uneven shrinkage of the foundation or walls is possible. Walls can sit in different ways on wooden houses, and foundations on layered or heaving soils. In all these cases, consider the device of this type of rafter system.

System for houses with two internal load-bearing walls

If the house has two load-bearing walls, two truss beams are installed, which are located above each of the walls. Benches are laid on the intermediate bearing walls, the load from the rafter beams is transferred to the benches through the racks.

Truss systems

In these systems, the ridge girder is not installed: it provides thrust forces. The rafters in the upper part are connected to one another (they are cut and docked without gaps), the joints are reinforced with steel or wooden lining, which are nailed.

In the upper non-thrust system, the tightening force is neutralized by the tightening. Please note that the tightening is placed under the purlin. Then it works effectively (top diagram in the figure). Stability can be provided by uprights, or joists - beams installed obliquely. In the spacer system (in the picture it is below), the cross member is the crossbar. It is installed over the purlin.

There is a variant of the system with racks, but without the rafter beams. Then a stand is nailed to each rafter leg, which rests on the intermediate load-bearing wall with the second end.

Fastening the rack and tightening in the rafter system without a rafter girder

For fastening the racks, 150 mm nails and 12 mm bolts are used. Dimensions and distances in the figure are in millimeters.

Gable roof rafter system: device, nodes

A significant part of private houses are covered with a gable roof. To support it, you need a correctly selected rafter system and well-made nodes.

The structure of the gable roof truss system

In section, the gable roof is a triangle. It consists of two rectangular inclined planes. These two planes are connected at the highest point into a single system by a ridge bar (run).

Now about the components of the system and their purpose:

Mauerlat - a beam that connects the roof and walls of the building, serves as a support for the rafter legs and other elements of the system.
Rafter legs - they form the inclined planes of the roof and are the support for the sheathing under the roofing material.
Ridge girder (bead or ridge) - unites two roof planes.
Tightening is a transverse piece that connects opposite rafter legs. Serves to increase the rigidity of the structure and compensate for bursting loads.
Beds are bars located along the Mauerlat. Redistribute the load from the roof.
Side Girders - Supports the rafter legs.
Racks - transfer the load from the girders to the benches.

There are quite a few constructions of truss systems. First of all, they are divided into two groups - with layered and hanging rafters.

With hanging rafters

The hanging type of the gable roof rafter system is good in that in most cases there is no need to install a Mauerlat, and this makes the installation of rafter legs easier: you do not need to make cuts, it is enough to mow the boards. To connect the walls and rafters, a lining is used - a wide board, which is attached to studs, nails, bolts, crossbars. With such a structure, most of the bursting loads are compensated, the impact on the walls is directed vertically downward.

Types of rafter systems with hanging rafters for different spans between load-bearing walls

Gable roof rafter system for small houses

Ridge knot and fastening of rafter legs to the underlay board with a simple system version

For mansard roofs

The variant with the installation of the crossbar is used for. In this case, it is the basis for filing the ceiling of the room below. For reliable operation of this type of system, the crossbar cut must be non-hinged (rigid). The best option is semi-rotten (see the picture below). Otherwise, the roof will become unstable to loads.

For large houses

With a significant distance between the two outer walls, a headstock and struts are installed. This design has high rigidity, since the loads are compensated.

With layered rafters

Spreader-free schemes and cutting units

The simplest spreader-free diagram of the rafter system is shown in the photo below. In it, the rafter leg rests on the Mauerlat. In this version, it works for bending without bursting the wall.

The version with the rafter legs fastened in the ridge part is much easier to assemble. They almost never give space to the walls.

Reinforcement of the ridge knot for heavy roofing material or with significant snow loads

Variants of rafter systems with scrapes

Attached to the rafter legs with bots or nails. Can be installed on one or two sides. See the figure below for attaching the scrum to the rafters and ridge girder.

Systems of layered rafters with struts

But not all houses have the middle load-bearing wall in the middle. In this case, it is possible to install struts with a tilt angle relative to the horizon of 45-53 °.

System for houses with two internal load-bearing walls

There is a variant of the system with racks, but without the rafter beams. Then a stand is nailed to each rafter leg, which rests on the intermediate load-bearing wall with the second end.

Fastening the rack and tightening in the rafter system without a rafter girder

For fastening the racks, 150 mm nails and 12 mm bolts are used. Dimensions and distances in the figure are in millimeters.

When designing any residential building, architects pay special attention to the roof, since it performs not one, but several functions at once, depending on its design features. It must be said that not all future homeowners are satisfied with the usual gable roof, although it can be called the most reliable, since it has only two pitched planes and one joint between them. Many are attracted by more complex structures that add special appeal and originality to the structure. Other, more practical homeowners prefer skylights that can serve as both a roof and a second floor at the same time.

The basis of any roof is an individual rafter system, which has its own design features. It will be much easier to make the choice of the desired roof frame if you figure out in advance which types and diagrams of rafter systems used in construction practice. After receiving such information, it will become more clear how complex such structures are in installation. This is especially important to know if the roof frame is supposed to be erected independently.

The main functional tasks of roof systems

When arranging pitched roof structures, the rafter system is a frame for covering and for holding the materials of the "roofing pie". With the correct installation of the frame structure, the necessary conditions will be created for the correct and non-insulated types of roofs that protect the walls and the interior of the house from various atmospheric influences.

The roof structure is also always the final architectural element of the exterior design of the building, supporting its stylistic direction with its appearance. Nevertheless, the design features of the rafter systems must first of all meet the strength and reliability requirements that the roof must meet, and only then - the aesthetic criteria.

The frame of the rafter system forms the configuration and angle of inclination of the roof. These parameters largely depend on natural factors specific to a particular region, as well as on the desire and capabilities of the homeowner:

The amount of precipitation in different periods of the year.
The direction and average speed of the wind in the area where the building will be erected.
Plans for the use of space under the roof - arranging residential or non-residential premises in it, or using it only as an air gap for thermal insulation of the premises below.
A type of planned roofing material.
The financial capabilities of the homeowner.

Atmospheric precipitation and the strength of wind flows give a very sensitive load on the roof structure. For example, in regions with heavy snowfalls, you should not choose a rafter system with a small angle of inclination of the slopes, since the snow masses will linger on their surface, which can lead to deformation of the frame or roofing or to leaks.

If the area where the construction will be carried out is famous for its winds, then it is better to choose a structure with a slight slope of the slope so that sudden gusts that occur do not tear off individual elements of the roof and roof.

Basic elements of the roof structure

Details and assemblies of rafter systems

Depending on the type of rafter system chosen, the structural elements used can vary significantly, however, there are details that are present in both simple and complex roof systems.

The main elements of the rafter system of a pitched roof include:

Rafter legs that form the roof slopes.
- a wooden beam, fixed on the walls of the house and serving to fix the lower part of the rafter legs on it.

The ridge is the joint of the frames of the two slopes. It is usually the highest horizontal line of the roof and serves as the support on which the rafters are anchored. The ridge can be formed by rafters, fastened together at a certain angle, or fixed on the ridge board (run).
The lathing is slats or beams mounted on rafters with a certain pitch and serving as the basis for the flooring of the selected roofing material.
Retaining elements, which include benches, girders, racks, struts, ties and other parts, serve to increase the rigidity of the rafter legs, support the ridge, and tie individual parts into a common structure.

In addition to the above-mentioned structural details, other elements can be included in it, the functions of which are aimed at strengthening the system and optimal distribution of the roof loads on the walls of the building.

The rafter system is divided into several categories, depending on the different features of its design.

Attic space

Before moving on to considering different types of roofs, it is worthwhile to figure out what an attic space can be, since many owners successfully use it as utility and full-fledged living quarters.

The design of pitched roofs can be divided into attic and attic roofs. The first option is called this way because the space under the roof has a low height and is used only as an air gap that insulates the building from above. Such systems usually include or has several slopes, but located at a very slight angle.

The attic structure, which has a sufficiently large ridge height, can be used in different ways, be insulated and not insulated. These options include the attic or gable version. If a roof with a high ridge is chosen, then it is imperative to take into account the wind loads in the region where the house is built.

The slope of the slopes

To determine the optimal slope of the roof slopes of a future residential building, first of all, you need to take a closer look at the already built low-rise neighboring houses. If they have been standing for more than one year and can withstand wind loads, then their design can be safely taken as a basis. In the same case, when the owners set the goal to create an exclusive original project, unlike the buildings standing nearby, it is necessary to familiarize yourself with the design and operational features of various rafter systems and make the appropriate calculations.

It should be borne in mind that the change in the tangential and normal values of the wind force depends on how large the slope of the roof slopes is - the steeper the angle of inclination, the more important are the normal forces and the less tangential. If the roof is sloping, then the shear wind load affects the structure more, since the lifting force increases from the leeward side and decreases from the windward side.

The winter snow load must also be taken into account when designing the roof. Usually, this factor is considered in conjunction with the wind load, since the snow load on the windward side will be much lower than on the leeward slope. In addition, there are places on the slopes where snow will necessarily collect, giving a large load on this area, so it should be strengthened with additional rafters.

The slope of the roof slopes can vary from 10 to 60 degrees and should be selected not only taking into account the consolidated external load, but also depending on the roofing to be used. This factor is taken into account because roofing materials differ in their weight, their fixing requires a different number of elements of the rafter system, which means that the load on the walls of the house will also differ, and how large it will be, also depends on the angle of the roof slope. Of no small importance are the features of each coating in terms of resistance to moisture penetration - in any case, many roofing materials need one or another slope to ensure the free flow of storm water or melting snow. In addition, when choosing the slope of the roof, you need to think in advance about how the process of cleaning and repair work on the roof will be carried out.

When planning this or that angle of the roof slopes, you need to know that the fewer joints between the sheets of the coating, and the more airtight they are, the less you can make the slope of the slope, of course, if it is not supposed to arrange a residential or utility room in the attic space.

If a material consisting of small elements is used to cover the roof, for example, ceramic tiles, then the slope of the slopes must be made steep enough so that water never lingers on the surface.

Given the weight of the roofing material, you need to know - the heavier the coating, the greater the angle of the slopes, since in this case the load will be correctly distributed to the rafter system and load-bearing walls.

The following materials can be used to cover the roof: either a profile sheet, galvanized steel, corrugated asbestos concrete and bitumen-fibrous sheets, cement and ceramic tiles, roofing material, soft roofing and other roofing materials. The illustration below shows the acceptable slope angles for various types of roofing.

Basic constructions of truss systems

First of all, it is worth considering the basic types of rafter systems in relation to the location of the walls of the house, which are used in all roof structures. Basic options are divided into layered, hanging, and also combined, that is, including elements of both the first and second types of systems in its design.

rafters

Nasal system

In buildings where internal load-bearing walls are provided, a layered rafter system is often installed. It is much easier to mount it than a hanging one, since the internal load-bearing walls provide reliable support for its elements, and in addition, this structure will require fewer materials.

For rafters in this system, the defining reference point is the ridge board, on which they are fixed. The non-thrust type of the layered system can be equipped in three options:

In the first version, the upper side of the rafters is fixed on a ridge support, called sliding, and their lower side is fixed by cutting to the Mauerlat. Additionally, the rafters in the lower part are fixed to the wall using wire or staples.

In the second case, the rafters in the upper part are cut at a certain angle and interconnected with the help of special metal plates.

The lower edge of the rafter legs is attached to the Mauerlat with movable fasteners.

In the third version, the rafters are rigidly fastened in the upper part with bars or treated boards, located horizontally, parallel to each other on both sides of the rafters connected at an angle, and the ridge girder is pinched between them.

In the lower part, sliding fasteners are used to secure the rafters, as in the previous case.

It is necessary to explain why sliding fasteners are often used to fix the rafters on the Mauerlat. The fact is that they are able to relieve the load-bearing walls of excessive stress, since the rafters are not rigidly fixed, and when the structure shrinks, they can move without deforming the overall structure of the roofing system.

This type of fastening is used only in layered systems, which also distinguishes them from the hanging version.

However, in some cases, a spacer system is used for layered rafters, in which the lower end of the rafters is rigidly fixed to the Mauerlat, and in order to remove the load from the walls, puffs and struts are built into the structure. This option is called complex, since it includes elements of a layered and hanging system.

The roof is a structure that serves as the end of the house at the top of it

Roof construction is one of the most important moments in the process of building a house. When constructing a roof, it is very important to follow the roof installation technology, the violation of which can lead to troubles: loss of heat, leakage or even distortion and destruction of the entire roof frame. In order for the roof to cope with its protective functions, it must be properly built.

The roof is an essential element of any building. Regardless of the type of roof and the materials from which it is made, this structure must be durable and fulfill its main functions. The main purpose of each roof is to protect the building from any bad weather, and in the case of the attic floor - to serve as a high-quality hydro and heat insulator.

The roof structure, designed in accordance with the expected loads and architectural features of the building, will not only decorate the structure, but also provide it with reliable protection. The more carefully the structure of the roof is thought out and the more accurate the calculations of the parameters of the constituent elements of its structure are, the more practical it will be in the course of further operation.

Based on the slope of the roofing system, they can be pitched or flat. The latter are installed horizontally or with a slope not exceeding 3%. Pitched roofs consist of inclined planes intersecting with their tops - slopes.

The slope of such roofs is calculated based on the used roofing material. So, when covering a roof with ceramic tiles, the slope is determined by the ratio 1: 2, and if with sheets of metal tiles - 1: 3 (L = 16). Roofs with a slope of 15% or more are classified as steep, up to 15% - flat.

What parts does the roofing system of buildings consist of?

Regardless of the features of the structure on which the installation of the roof is planned, its structure is assembled from the following main elements:

mauerlat;
rafter system;
lathing;
waterproofing;
thermal insulation;
vapor barrier;
roofing material.

Roofing system design

Mauerlat acts as a solid foundation for roof structures. This is a top rail made of beams made of wood or reinforced concrete. The bars must be firmly attached to the walls of the structure. The upper surface of beams or wooden logs should be horizontal, since the rest of the structural elements will be mounted on it in the future. To protect the wood of the beams from moisture, several layers of roofing material can be laid on them.

It is the most important part of the roof structure, determining its shape and providing the necessary protection and stability to the entire building. Often, the characteristics of a given roof element determine its type and shape and allow the creation of unique roofing systems. The rafters must withstand not only the effects of weather conditions, but also the total weight of the roof. Usually, the size of the timber for the frames of the truss systems is 5x15 cm.

Important!
To evenly distribute the load, the rafter beams are reinforced with additional supports: spacers laid on the Mauerlat parallel to the rafters, vertical uprights, inclined struts, as well as ridge and side girders located across the rafters.

The stability and strength of the roof entirely depends on its supporting structure - the rafter system

To fasten the roofing material, a crate of small strips or boards is laid on the rafters. Wooden boards are placed at a certain distance from each other, depending on the type of roofing material. If the roofing is of a roll type, the pitch of the lathing should be no more than 1 cm.Under metal tiles or polycarbonate sheets, a pitch of about 60 cm is optimal.

For waterproofing, namely protecting the roof from moisture penetration from the outside, a layer of a special film is used. It can be placed under or on top of the batten, avoiding excessive tension and sagging of the layer. At the joints of the canvas, the films are laid with an overlap of 20 cm in size and firmly fixed with construction tape.

There is a large selection of thermal insulation materials for roof insulation. They can be stacked or sprayed between the rafter joists without leaving gaps. Uneven distribution of insulation can adversely affect the quality of the thermal insulation layer and lead to a decrease in its performance.

Important!
To prevent the accumulation of excess moisture in the roofing system, it is necessary to arrange special gaps to ensure sufficient ventilation.

Thermal insulation of the roof allows not only to make the house more comfortable, and the microclimate in it, but also to reduce energy costs by 30%

To protect against moisture penetration into the roof from the inside of the structure, the insulation is covered with another layer of film. Special membrane films are designed in such a way as to absorb water vapor without letting it inside the roof. In the future, the absorbed moisture gradually evaporates.

The uppermost part and face of the roof is the roofing material. To cover the roof, metal sheets, slate, corrugated board, roofing steel are mainly used. Less commonly, roofs are made of polycarbonate, ceramic tiles, glass.

Metal tile is a very popular material for creating a reliable roof of any building

Types of roof structures depending on the shape

In terms of shape, there are a wide variety of roofing options. In modern construction, the installation of pitched roofs is mainly carried out. Horizontal structures cannot fully protect the building from adverse weather conditions. A lot of snow is retained on their surface, and during rain, moisture can seep into the building.

Pitched roof shapes

Pitched roofs differ in the number of pitched roofs. The simplest and most economical single slope roof structure. The frame system of such a roof is mounted on the walls of the house with a certain slope, due to the fact that they have different heights. On the attic floor with such a roof, it will not be possible to equip a residential attic. And the building looks rustic with such a roof. Such polycarbonate roofs are often built on terraces, balconies, verandas.

Shed roof construction is extremely simple

Gable

Gable (gable) roofs are widely used in the construction of a wooden house in the suburbs or private buildings in small towns. Often it can be found in country buildings. 2 slopes of such a roof are interconnected by means of a ridge - a horizontally located rib. This type of roofing is the most common and most practical. The space under such a roof, bounded on the sides by parts of the walls of the structure, can be used as an attic or attic. The original look of the building can be given by installing ramps that differ in width or slope angle.

A gable roof is the most popular construction in private construction

Varieties of hip roofs

Hip roof (Dutch) is a very reliable and durable construction made in European style. Its frame consists of 4 slopes: 2 triangular, located instead of pediments, and 2 trapezoidal slopes. The construction of such a roof is a rather complicated and time-consuming process, but the result justifies the efforts made.

Advice!
Sometimes, in order to achieve a triangle shape on the unused part of the pediment, its lower part is covered with a slope. In this part, a window is usually mounted.

Even more complex in execution is the half-hip type of roofs. Such a roof has truncated triangular slopes located above the trapezoidal ones. In addition to additional attractiveness, it is characterized by high functional qualities. In addition, the half-hip design allows you to arrange a rather large window on the pediment.

Half-hip roofs are one of the most interesting options borrowed from Northern European architecture.

Hip frame roofing is also a type of hip type. It is formed by three or more slopes, with their tops connected at the top at one point. The peculiarity of this roof is the absence of a ridge. Symmetrical triangular slopes create an impressive design. This type of roof is usually used in houses with a polygonal or square shape.

Multi-gable design

For installation in structures of a polygonal shape, a multi-gable frame roof is suitable. This type of roof is a rather complex structure and requires a carefully thought out, precisely drawn up plan.

A multi-gable roof will require colossal physical and financial costs, but will delight the creators with the architectural beauty of the building.

For the construction of a residential attic, a broken roof is installed on the attic floor. The fractures of its slopes have a significant angle of inclination, which ensures the formation of a large free space under the roof.

Broken roof structure allows to increase the functionality of the building

Dome roof structure

Rounded roofs in the form of a cone or dome are not installed along the entire perimeter of the building. They cover such building elements as decorative turrets or rounded terraces.

Dome houses are a relatively new word in construction, quickly gaining popularity due to the use of unconventional forms.

Combined roof options

Combined roof structures can combine a wide variety of frame types.

Combined roofing can include various elements of hip roofs. The multi-gable design can be equipped with a large number of compact glass windows, small balconies, as well as polycarbonate verandas or terraces. Thus, they allow you to embody the most daring and original design solutions. Their main disadvantage is complex installation and rather expensive maintenance.

Combined roofs - the most complex in structure

What type of roofing system to choose for a private house

In construction practice, a wide variety of types are used. Basically, the rise of this or that type of roof depends on the wishes and financial capabilities of the owner of the house. Currently, it is possible to install the most unusual roofing systems: glass, metal, polycarbonate, ceramic or metal roofing.

Giving preference to any type of roof, the owner of a private house thereby determines the features of the future frame truss system. It is also taken into account in what weather conditions the building will be located, how the use of the attic space is planned. If a residential attic is planned, the desired number of rooms in the space under the roof, as well as their purpose, are taken into account.

A flat roof is a fashionable architectural way of building a roof for a country house, which has a number of advantages and functional features

Roof covering materials

Various building materials are used to cover roof structures: rigid and flexible, piece and rolls, profiled and flat. Some use it for the roof of a small house, others for a multi-storey city building, and still others for household buildings.

Sheet roof:

sheets of metal tiles;
corrugated board;
ondulin (euro slate, aqualin);
slate;
copper folded sheets, as well as aluminum or steel.

Profiled sheet and metal tiles are valued, first of all, for their durability. Slate is a more budget option. A folded covering, in contrast to metal tiles, is more often used when sheltering industrial buildings.

Decking is one of the best building finishing materials in terms of price-quality ratio

Soft types of materials:

flexible tile. A multi-gable structure is mainly mounted from it;
roll roofing (stekloizol, waterproofing);
membrane roofing (EPDM, TPO, PVC), for example, polycarbonate sheets.

Piece materials:

ceramic tiles;
bulk (mastic);
slate roof.

In the construction of country houses, polycarbonate covers are often mounted. Thanks to its features, the roof is durable and lightweight. This material is durable and lightweight, transmits daylight and is an alternative to glass coatings. Polycarbonate roofing is used in the construction of terraces, attics, verandas, greenhouses. Due to the presence of air chambers, polycarbonate sheets are distinguished by high sound insulation and excellently retain heat inside the room. In addition, the cost of polycarbonate is lower than glass coatings.

A gazebo with a polycarbonate roof is a very good option for installation in summer cottages of any size

Functions and types of structures of the eaves of the roof

The overhang of the eaves protruding beyond the perimeter of the walls of the house is designed to protect against precipitation. The cornice elements mask the line of connection between the inner surface of the roof slopes and the walls of the house and make the building façade complete.

Eaves overhangs are equipped on the sides of the building and on the side of its facade due to the protruding edges of the inclined slopes. The overhang of the side cornice is usually 50 cm, the frontal - about 1 m.

To ensure the safe operation of the front cornice, it is necessary to take a responsible approach to the choice of materials.

Important!
An important point when finishing the cornice is the mandatory provision of adequate ventilation, regardless of the type of design chosen and the size of the cornice.

In total, the number of ventilation openings should be up to 1/400 of the area of the interior space.

The device of the eaves of the roof provides an additional function of ventilation of the under-roof space

Types of roof structures

The roof frame system is an important structural element of any building. Depending on the materials of manufacture, roof frames are divided into the following types:

a concrete-type frame structure is used for the manufacture of flat or shallow single-slope systems, consists of special slabs;
the roofing system of the truss type is a frame made of lumber. This option is best suited for the installation of various types of pitched roofs;
in industrial houses, it is advisable to install metal roof frames made of durable metal beams;

In the construction of private houses, mainly a frame gable roof made of lumber is used.

Important!
The roof frame is subjected to heavy loads during operation. To ensure the safety and reliable protection of the building, it must be as strong and high quality as possible.

Construction of a frame house with a multi-gable roof attic

For the construction of the roof of a multi-storey apartment building, metal or concrete single-slope structures are often used.

The choice of the shape of the roof and the variety of roofing material is largely determined by the features of the architectural configuration of the structure, weather conditions, the planned direction of water flow, as well as the individual preferences of the owner of the house. Regardless of the type of roof, if desired, it can be supplemented and old elements replaced with new ones.

Various roof designs. Part 1

Various roof designs. Part 2

Roof components. Roof composition - roof elements. How the structure of the rafter system works, which one is better to choose

Roof structural elements

Geometric roof shapes

Rafters

General conclusions

Functional features of a gable roof

Gable roof rafter system

How the structure of the rafter system works, which one is better to choose

The purpose of the rafter system

Features of choice

Types of rafters

Structural elements and details

Types of rafter system

Arrangement and installation of a wooden truss system

Roof and roof

System Requirements

Parts of the structure

Roof shapes

Types of rafters

Connections

Types of gable roof truss system: for small and large houses

The structure of the gable roof truss system

With hanging rafters

With layered rafters

Systems of layered rafters with struts

System for houses with two internal load-bearing walls

The structure of the gable roof truss system

With hanging rafters

Gable roof rafter system for small houses

For mansard roofs

For large houses

With layered rafters

Spreader-free schemes and cutting units

Variants of rafter systems with scrapes

Systems of layered rafters with struts

System for houses with two internal load-bearing walls

The main functional tasks of roof systems

Basic elements of the roof structure

Details and assemblies of rafter systems

Attic space

The slope of the slopes

Basic constructions of truss systems

Nasal system

Rafter length calculator

Gable rafter system

What parts does the roofing system of buildings consist of?

Types of roof structures depending on the shape

Gable

Varieties of hip roofs

Multi-gable design

Dome roof structure

Combined roof options

What type of roofing system to choose for a private house

Roof covering materials

Functions and types of structures of the eaves of the roof

Types of roof structures