As a rule, softwood lumber is used.

For various elements and parts of the wooden rafter system, wood of a certain type and grade is used. When using lumber in a rafter-beam system, the following properties and indicators of wood must be taken into account: bending strength, compression, chipping, wood density and moisture content.

Wooden rafter structures must necessarily comply with the special degree of fire resistance of the room. They must be treated with special fire retardants and...

There is a huge variety variety of options and elements of the arrangement of wooden rafter structures. There are the following types of rafter structures: layered or hanging rafters, combined, with a tie, etc. The most popular rafter structures are layered and hanging.

To avoid sagging of the entire structure, a horizontal tie is attached to the lower end of the beam using strip steel clamps to support the entire beams attic floor. If the span is up to 12 m, then struts are introduced into the rafter structure, which reduce the estimated length of all rafter legs.

Hanging wooden rafters work in both compression and bending.

Below we consider the types of rafter structures:

1. ordinary hanging rafters
2. double hanging rafters

It is not uncommon to increase the entire area of ​​the attic space in a system of wooden hanging rafters without using tie-downs, but using struts.

Roof Mauerlat

In this case, the rafter legs are cut into the Mauerlat itself. The lower plane should lie on the wall, and in the upper one you need to make certain cuts for correct connection with rafter legs.

All struts rest against the end of the wooden one. In this case, the loads that would be compensated by the tightening are directly transferred to all walls. As a result, this solution for a wooden rafter system is only possible if there is a special massive structure.

Hanging rafters are parts and elements of rafter structures that are located in one vertical plane and are connected to each other using notches, bolts, nails, clamps and staples.

There is a combined rafter system - this is the installation of both layered and hanging truss structure, which alternate in turns. Where there are no intermediate supports, hanging rafter systems are used, and where they are present, layered rafter systems are used.

Rafters with tie

Used for spans up to 15 m. Spans of this length require certain intermediate struts, i.e. in special puffs. They are mounted at the height of the building between two rafters and tied together. And longitudinal struts will prevent lateral bending.

Tightening the roof rafters

All structures with retaining wooden beams must be assembled in the form of rafter structures reinforced with special supports, which will rest on transverse beams and all load-bearing walls, as well as in the form of truss systems. The concept of sprengel is structural element according to the type of open triangular rod system, which is attached to the main truss load-bearing structures.

The structural rigidity of this roof is provided by a longitudinal strut or strut. The use of struts reduces the overall load on the entire structure. Vertical struts are usually attached to either racks using notches, trunnions, or steel plates.

Truss hanging timber trusses systems

Sprengel

The entire load from the rafter legs goes to the racks, which transfer it further to the load-bearing main ones. With this design, the load will be distributed between all load-bearing walls. The racks are mounted at the ends of the main load-bearing walls. The lower ends of all racks are secured using hanging pins.

Truss beams are made from solid solid wood or laminated boards. Usually they are small in height. Good and high quality load bearing capacity truss beams are installed using a truss system and wooden beams supporting it.

Shrengel beams can cover huge spans. Sometimes they are equipped with steel belts.

Complex rafter system designs

Available by type roof trusses. Lattice trusses are divided into types according to the shape of their openings: triangular, trapezoidal or parallel belts. Typically, lattice trusses are made symmetrical, but other options are possible, for example,. A common lattice truss includes top and bottom chords, posts and braces.

Reliable and quality connection carrying wooden structures with central supports into one common system called a frame. The racks and beams connected into the frame are necessarily fastened or included in each other. Today there are two main types of frames - double-hinge and three-hinge. Double-hinged frames are equipped with a crossbar that runs across the entire width of the finished frame. Frame data the best way suitable for structures with a small angle of inclination. Tri-hinged frames consist of two equal halves that support each other at the ridge of the roof. Three-hinge frames are used where a more significant angle of inclination is required.

Trust the calculations of rafter structures and the final selection of their elements and parts to specialists. Huge loads are applied. In addition to its own weight, it is affected by wind loads, heavy rains, hail, snow and ice. The roof quite often undergoes various

The rafters serve as the basis for the entire roofing structure, and their installation is one of the most important tasks when building a house. The frame of the future roof can be made and installed independently, observing the technological features of roofs of different configurations. We will present the basic rules for the development, calculation and selection of a rafter system, and also describe the step-by-step process of installing the “skeleton” of the roof.

Rafter system: rules for calculation and development

Rafter system - Basic structure, capable of resisting gusts of wind, taking on all external loads and evenly distributing them onto the internal supports of the house.

When calculating the truss structure, the following factors are taken into account:

1. Roof angle:
   • 2.5-10% - flat roof;
   • more than 10% - pitched roof.
2. Roof loads:
   • permanent - total weight all elements of the “roofing cake”;
   • temporary - wind pressure, the weight of snow, the weight of people carrying out repair work on the roof;
   • force majeure, for example, seismic.

The amount of snow loads is calculated based on the climate characteristics of the region using the formula: S=Sg*m, Where Sg- weight of snow per 1 m2, m-calculation coefficient (depending on the slope of the roof). The determination of wind load is based on the following indicators: type of terrain, regional wind load standards, building height.

Coefficients, required standards and calculation formulas contained in engineering and construction reference books

When developing a rafter system, it is necessary to calculate the parameters of all components of the structure.

Elements of the truss structure

The rafter system includes many components that perform a specific function:

Materials for making rafters

Rafters are most often made from coniferous trees (spruce, larch or pine). For roofing, well-dried wood with a humidity level of up to 25% is used.

The wooden structure has one significant drawback - over time, the rafters can become deformed, so metal elements are added to the supporting system.

On the one hand, metal adds rigidity to the rafter structure, but on the other hand, it reduces the service life of wooden parts. Condensation settles on metal platforms and supports, which leads to rotting and damage to the wood.

Advice. When installing a rafter system made of metal and wood, care must be taken to ensure that the materials do not come into contact with each other. You can use moisture-proofing agents or use film insulation

In industrial construction they use metal rafters, made of rolled steel (I-beams, T-beams, angles, channels, etc.). This design is more compact than wood, but retains heat less well and therefore requires additional thermal insulation.

Choosing a rafter system: hanging and suspended structures

There are two types of rafter structures: hanging (spacer) and layered. The choice of system is determined by the type of roof, floor material and natural conditions region.

Hanging rafters rest solely on the external walls of the house, intermediate supports are not used. Hanging type rafter legs perform compression and bending work. The design creates a horizontal bursting force that is transmitted to the walls. Using wooden and metal ties you can reduce this load. The ties are mounted at the base of the rafters.

A hanging rafter system is often used to create an attic or in situations where roof spans are 8-12 m and additional supports are not provided.

Layered rafters mounted in houses with an intermediate columnar support or additional load-bearing wall. The lower edges of the rafters are fixed on the external walls, and their middle parts are fixed on the internal pier or load-bearing pillar.

Installation of a single roofing system over several spans must include spacer and layered roof trusses. In places with intermediate supports, layered rafters are installed, and where there are none, hanging rafters are installed.

Features of arranging rafters on different roofs

Gable roof

Gable roof, according to building regulations, has an inclination angle of up to 90°. The choice of slope is largely determined by the weather conditions of the area. In areas where heavy rainfall prevails, it is better to install steep slopes, and where strong winds- flat roofs to minimize the pressure on the structure.

A common version of a gable roof is a design with a slope angle of 35-45°. Experts call such parameters the “golden mean” of consumption of building materials and load distribution along the perimeter of the building. However, in this case attic space It will be cold and it will not be possible to arrange a living room here.

For a gable roof, a layered and hanging rafter system is used.

Hip roof

All roof slopes have the same area and the same angle of inclination. There is no ridge girder here, and the rafters are connected at one point, so the installation of such a structure is quite complicated.

It is advisable to install a hip roof if two conditions are met:

• the base of the building is square in shape;
• in the center of the structure there is a load-bearing support or wall on which it will be possible to fix a rack that supports the junction of the rafter legs.

Create hip roof it is possible without a stand, but the structure must be strengthened additional modules- stand-up puffs.

Hip roof

Traditional design hip roof assumes the presence of slanted rafters (diagonal) directed towards the corners of the building. The slope angle of such a roof does not exceed 40°. Diagonal runs are usually made with reinforcement, since they account for a significant part of the load. Such elements are made from double boards and durable timber.

The joining points of the elements must be supported by a stand, which increases the reliability of the structure. The support is located at a distance of ¼ of the length of the large rafters from the ridge. Shortened rafters are installed in place of the gable roof gables.

Rafter structure hipped roof may include very long diagonal elements (more than 7 m). In this case, a vertical post must be mounted under the rafters, which will rest on the floor beam. You can use a truss as a support - the beam is located in the corner of the roof and fixed to adjacent walls. The truss truss is reinforced with struts.

broken roof

Sloping roofs are usually created to accommodate a larger attic. The installation of rafters with this roofing option can be divided into three stages:

1. Installation of a U-shaped structure - supports for purlins that hold the rafter legs. The base of the structure is floor beams.
2. At least 3 purlins are installed: two elements run through the corners of the U-shaped frame, and one (ridge purlin) is mounted in the center of the attic floor.
3. Installation of rafter legs.

Gable roof: do-it-yourself rafter installation

Calculation of inclination angle and loads

Calculation gable roof Of course, you can do it yourself, but it’s still better to entrust it to professionals in order to eliminate errors and be confident in the reliability of the design.

When choosing the angle of inclination, it is necessary to take into account that:

• an angle of 5-15° is not suitable for all roofing materials, so first choose the type of coating, and then calculate the rafter system;
• at an angle of inclination over 45°, material costs for the purchase of components of the “roofing cake” increase.

Load limits from snow exposure range from 80 to 320 kg/m2. Calculated coefficient for roofs with a slope of less than 25° is 1, for roofs with a slope from 25° to 60° - 0.7. This means that if there are 140 kg of snow cover per 1 m2, then the load on a roof with a slope at an angle of 40° will be: 140 * 0.7 = 98 kg/m2.

To calculate the wind load, the aerodynamic influence coefficient and wind pressure fluctuations are taken. The value of the constant load is determined by summing the weight of all components of the “roofing cake” per m2 (on average 40-50 kg/m2).

Based on the results obtained, we find out the total load on the roof and determine the number of rafter legs, their size and cross-section.

Installation of Mauerlat and rafters

Do-it-yourself installation of rafters begins with the installation of a mauerlat, which is fixed with anchor bolts to the longitudinal walls.

Further construction of the structure is carried out in the following sequence:

Installation of rafters: video

Methods for connecting rafter structure elements: video

Perhaps the main decoration of any house is the roof, without which it is difficult to imagine any structure. The roof gives a private home a holistic appearance and defines his style. However, first of all, it acts as an engineering structure designed to protect people from the destructive effects of the external environment.

Today, the use of various architectural elements in the construction of houses, undeservedly forgotten earlier, is returning to fashion. For example, mezzanines, bay windows, and attics are becoming more and more common, giving the building a stylish and interesting exterior. At the same time, you can achieve a noticeable increase in internal space at a relatively low cost of money.

The roof truss system is considered the most strong, durable structure. It is characterized by ease of installation, ease of adjustment and the ability to withstand heavy loads, with a relatively light weight. The rafter system is a special structure, with a triangle at the base. Its rigidity is achieved by fastening the rafters and the roof frame together. The most common options are made from wooden logs or beams, however, there are also systems made from galvanized steel.

Types of rafter systems

Experts distinguish several types of rafter systems. They are accepted classified by roof shape and type:

• hipped;
• tri-slope;
• gable;
• hip;
• half-hip;
• broken

Gable rafter system roof is the cheapest and simple option. The main advantages of this design include simplicity, reliability and the ability to withstand significant loads. At the same time, it is worth describing some disadvantages. Namely, the impossibility of implementing any special design solutions due to the simplicity of the shape of such a roof. However, this minus can easily be compensated by decorating the house with various decorative elements. The second drawback can be called more significant - inner space small in size, significantly different from the parameters of a sloping roof.

The most common and recognized among lovers of interesting architectural solutions is sloping roof truss system. In this case, there is an opportunity for the manifestation of imagination, of course, subject to established construction standards and strength characteristics. This design can be regular or asymmetrical in shape and is determined based on the structure of the house itself, as well as the design and layout of the interior of the room.

Sometimes you can get an extremely interesting room under the roof by correctly installing the rafter system and organically using a second light or mezzanine. In order to maximize, at relatively low financial costs, usable area home and make it cozy, it is very important to be able to effectively and fully use the available space.

Features and requirements for the rafter system

The size of the rafters, which are elements that determine the strength and slope of the roof, must be calculated individually for each private house, taking into account the total area and geometric shape of the roof, as well as the distance between the walls. Depending on the results obtained, it will be possible to determine the appropriate cross-section of the beams. As a rule, this figure is about 1 meter.

In practice they use two types of rafters:

1. An inclined structure, which rests on the walls of the house along the entire perimeter, and in the center it is supported by an additional or intermediate support. It is advisable to use if the distance between several supports is no more than 6.5 m.
2. Hanging rafters, fixed at the top at the ridge and resting on each other. This system is particularly reliable when connecting walls to each other.

In general, the design of the rafter system directly depends on the type of material from which the house is made. For example, for a building built of brick, a rafter system is recommended that rests on a separately constructed support made of small-section beams or a mauerlat. As a support for rafters wooden structure The top crown of the log house is best suited, and for frame-type houses the top frame is used.

Main parts of the roof truss system

The basis of the roof on which it is made roofing pie installation And internal lining premises, is precisely the rafter system. It is often also used as a basis for communications and engineering systems. The set of various components and elements that make up the roof truss system performs the function of transferring power loads directly from the roof to the load-bearing walls of the structure. The main parts include:

• Hanging and inclined rafters.
• Mauerlat.
• Ridge and side girders.
• All kinds of connecting elements, such as struts, diagonal braces, spacers.

As a rule, the load on the roof truss structure is very high. It is determined individually, taking into account design features roofs and local wind and snow loads. The installed rafters must guarantee the retention of such loads, and also have the necessary strength margin to withstand possible gusts of wind or snowfall.

In order to determine the main parameters of the components of the roof truss system, it is necessary perform special calculations. They will help to accurately determine the profile, length and cross-section of each of the structural elements, as well as the features of the interaction of the parts with each other. The strength of the entire structure largely depends on how tightly the units of the roof truss system are connected. Recommended use the following types of connections:

Which type of connection is applicable for a particular system can be determined based on the design load, design features and materials used.

Installation principles

Installation work carried out in three main stages. In particular, location-aware markup window openings, hoods, chimneys, mounting the Mauerlat and reliable fastening it to the supporting support. Next, the trusses are erected and, finally, the ridge is installed.

Installation should begin by laying the Mauerlat on top of the walls and attaching the rafters directly to it. They must be installed in the desired position and secured at one end to the support, and at the other to ridge beam. For reliability, the connections can be additionally secured to each other with studs with a diameter of 8 -12 mm.

When constructing a truss structure, the most common an error is an incorrect calculation rafter sizes, which can lead to sagging of the roof.

To provide for each element and node, to understand the technology, it is still necessary to preliminary stage. At the same time, it is also recommended to plan the eaves overhang with a length of 60 cm, which will reduce the effect of weather phenomena on the walls of the house.

For wooden structures that may dry out over time, the most the right option there will be fastenings bolted connections , capable of adding rigidity to the entire structure.

If you follow all the basic rules, installing a roof truss system can be done relatively easily. However, it is important to strictly adhere to the chosen technology to avoid the risk of various problems.

During construction one-story houses The roof with two slopes is very popular. This is due to the speed of construction of the structure. In this parameter, only a single-pitched roof can compete with a gable roof. The design of the gable rafter roof is not too complicated. And you will successfully master this work on your own.

Design of a gable roof truss system

A gable roof consists of two inclined surfaces that have rectangular shape. Thanks to this, precipitation, which is represented by rain and melt water, drains from the roof naturally. The gable roof has enough complex design. It consists of the following structural units: mauerlat, rafter system, fillies, ridge, roof overhang, bed, struts, tie-downs, sheathing and racks:

1. Mauerlat. This element performs the functions of transferring and distributing the load created by the rafter system onto the load-bearing walls of the house. To make the Mauerlat, timber is used, which has a square cross-section - from 100 by 100 to 150 by 150 mm. It is better to use coniferous wood. The timber is placed around the perimeter of the building and secured to the external walls. For fastening, special rods or anchors are used.
2. Rafter leg. Rafters form main frame any roof. In the case of a gable roof, they form a triangle. The rafters are responsible for the uniform transfer of loads to the Mauerlat. First of all, those that arise from precipitation, wind and the weight of the roof itself. For the manufacture of rafters, boards are used that have a cross-section of 100 by 150 or 50 by 150 mm. Choose a rafter pitch of about 60-120 cm, depending on the variety roofing material. When using heavy coverings, place rafter legs more often.
3. Horse. This element connects the two slopes at the top of the roof. The ridge is formed after connecting all the rafter legs.
4. Fillies. They act as a continuation of the rafters and form the overhang of the gable roof. It is customary to install fillies if the rafter legs are very short and do not allow the formation of an overhang. To make this structural unit, take a board that has a smaller cross-section than the rafter. The use of fillies facilitates the construction of the rafter system, as it allows the use of short rafters.
5. Eaves. This part of the design of the gable roof truss system is responsible for draining water from the walls during rain and at the same time preventing them from getting wet and quickly collapsing. The overhang from the wall, as a rule, protrudes 400 mm.
6. Sill. It is located on the inner wall and serves to evenly distribute the load from the roof pillars. To make the bed, a timber is used, which has a cross-section of 150 by 150 or 100 by 100 mm.
7. Racks. These vertical elements are responsible for transferring the load from the ridge to the internal walls. To create this element, prepare a beam that has a square section of 150 by 150 or 100 by 100 mm.
8. Struts. They are needed to transfer loads from the rafters to the load-bearing walls. The struts and tightenings form robust construction which is called a farm. Such a device is designed to withstand loads over large spans.
9. Puff. This structural unit, together with the rafters, forms a triangle. It does not allow the rafters to move in different directions.
10. Lathing. This structure consists of boards and bars. They are attached perpendicular to the rafters. Lathing is necessary to evenly distribute the weight of the roof covering and the loads created by weather conditions onto the rafters. In addition, sheathing is required to fasten the rafters together. When arranging a soft roof, moisture-resistant plywood should be used to create sheathing rather than boards and bars.

Types of gable roof rafter system

There are gable rafter systems with hanging and layered rafters. Ideally, the design contains a combination of them. It is customary to install hanging rafters if the external walls are located at a distance of less than 10 m. Also, between them there should no longer be walls that divide the space of the residential building. The design with hanging rafters creates a bursting force transmitted to the walls. It can be reduced if you make a tie made of wood or metal and place it at the base of the rafters.

The rafters and tightening form a rigid geometric figure- triangle. It is not capable of deforming under loads that appear in any direction. The tightening will be stronger and more powerful if it is positioned higher. The tie beams are the floor beams. Thanks to their use, the hanging rafter system of a gable roof serves as the basis for arranging the attic floor.

In their design, layered rafters have a support beam, which is placed in the middle. It is responsible for transferring the weight of the entire roof to the intermediate columnar support or middle wall located between external walls. It is recommended to install layered rafters if the external walls are located at a distance of more than 10 m. If there are columns instead interior walls, you can alternate between layered and hanging rafters.

DIY gable rafter system

The roof must be strong to withstand various loads - precipitation, gusts of wind, the weight of a person and himself. roofing, but at the same time light, so as not to put much pressure on the walls of the house. A properly constructed gable rafter roof evenly distributes the load across all load-bearing walls.

Calculation of a gable roof

The choice of slope for a gable roof will depend on the material you have chosen for laying on the roof and architectural requirements:

• When erecting a gable roof, remember that it must slope at an angle of more than 5 degrees. It happens that the roof slope reaches 90°.
• For areas with heavy rainfall, and when the roofing does not fit tightly, steep slopes are made. In this situation, the angle should be 35-40° so that precipitation does not linger on the roof. But such an angle does not allow building a living space in the attic. The solution will be a broken roof structure. It will have a flat top part, and at the bottom there is a sharp slope.
• In regions with strong gusts of wind, flat roofs are installed. If constant winds prevail in the area, then make a slope of 15-20° for high-quality protection of the roofing.
• It is best to choose the middle option. Make sure the gable roof is not too steep. But the slope should also not be very gentle.
• When choosing a large roof angle, its windage increases, and, accordingly, the price of the gable roof rafter system and sheathing increases. After all, such a slope entails an increase in the roof area and, accordingly, the amount required material- construction and roofing.

When purchasing materials for constructing a gable roof, it is useful to calculate its area:

1. Find the area of ​​one slope of the structure, and then double the result.
2. Ideally, the slope is an inclined rectangle that is placed along a long load-bearing wall. To determine the area of ​​the slope, multiply its length by its width.
3. The length of the slope is equal to the length of the wall. In addition, the length of the roof overhang above the gable is added to the length. Remember that there are tabs on both sides.
4. The width of the slope is the length rafter leg. The length of the roof overhang above the load-bearing wall is added to it.

In order to correctly design the structure, it is recommended to carry out an accurate calculation of the rafter system of a gable roof, including determining the loads and characteristics of the rafters:

1. When erecting a roof for a standard building that has one floor, the design load on the roof will consist of two values. The first of them is the weight of the roof, the second is the load from external factors: precipitation and wind.
2. Calculate the weight of the roof by adding up the weight of each layer of the “pie” - thermal insulation, vapor barrier and waterproofing materials, rafter system, sheathing and roofing material itself. Calculate the weight per 1 m2.
3. Increase results by 10%. You can also take into account the correction factor. In our case K=1.1.
4. If you plan to change the roof structure over time and increase its angle of inclination, then factor in a safety margin into the calculation. Immediately take higher loads than those you received at the time of calculation. It is recommended to start from a value of 50 kg per 1 m2.
5. When calculating the load exerted by atmospheric phenomena, take into account the climatic features of the area where the building is located. When making this calculation, take into account the slope of the slope. If the gable roof forms an angle of 25 degrees, then accept snow load, equal to 1.
6. If the roof is equipped with a greater slope - up to 60 degrees, the correction factor reaches 1.25. Snow loads for angles greater than 60 degrees are not taken into account.
7. The rafters transfer the entire load from the created structure to the load-bearing walls. Therefore, their parameters must be taken accordingly. Select the cross-section and length of the rafter leg, depending on effective load on the roof and the corner of the slope. Increase the obtained values ​​by 50% to ensure a high safety margin.

Mauerlat installation methods

The construction of any roof begins with the installation of the Mauerlat:

• If logs or beams were used to build the walls, then the top beam will act as a Mauerlat, as shown in the photo of the gable roof rafter system.
• If you used brick to build the walls, then wall up metal rods into the masonry. They must have a thread cut for attaching the Mauerlat. Install rods every 1-1.5 m. Choose rods with a diameter of at least 10 mm. Lay waterproofing between the masonry and the mauerlat.
• For walls made of ceramic or foam concrete blocks, pour concrete on top. Be sure to make the layer reinforced. It should have a height of approximately 200-300 mm. Be sure to attach metal rods that have threads to the reinforcement.
• For the Mauerlat, use a beam that has a cross-section of 15 by 15 cm. It will act as a kind of foundation for the rafter system.
• Place the Mauerlat on the top edge of the wall. Depending on its design, the Mauerlat can be laid along the outer and inner edges. Do not place it close to the very edge, otherwise the wind may blow it off.
• It is recommended to place the Mauerlat on top of the waterproofing layer. To connect all parts into one, use bolts and metal plates.
• To avoid sagging, make a lattice from racks, struts and crossbars. To do this, take boards measuring 25x150 mm. The angle between the strut and the rafter leg should be as straight as possible.
• If you use a rafter leg that is too long, install another support. She should rest on the bed. Each element is associated with two neighboring ones. The result is a stable structure around the entire perimeter of the roof.

Fastening rafter legs

The best option for a gable roof rafter system is a combination of inclined and hanging rafters. This design allows you to create a reliable gable roof and reduce costs Construction Materials. Consider the following recommendations when working:

1. Use only the highest quality wood as material. Beams that have cracks and knots should absolutely not be used.
2. The rafters have standard sizes- 50x150x6000 mm. When beams are longer than 6 m, it is recommended to increase the width of the board so that the beams do not break under their own weight. Take boards 180 mm wide.
3. First make a template for the rafter leg. Attach the board to the floor beam and the end of the ridge beam. Having outlined two lines, saw off the board along them. The template is ready.
4. Cut the rafters according to this template. After this, make the top cut on them.
5. Take the resulting workpiece and bring it to the floor beam to mark the bottom cut in place.
6. Install all rafters. At the same time, remember that after installing one leg, you must immediately install the opposite one. This way you will quickly remove the lateral loads on the ridge beam.
7. If the slope is too long, then standard boards will not be enough to make a rafter leg. In this case, you can join two boards together. To do this, sew on them a piece of wood of a similar cross-section. It should have a length of 1.5 - 2 meters. According to the gable roof rafter system diagram, the joint should always be at the bottom. Install an additional stand under it.
8. Attach the rafter leg to the ridge beam using nails. To attach the rafters to the floor beam, use self-tapping screws. Metal mounting plates are also suitable. In addition, a few nails are added.
9. If you are building a structure entirely from hanging rafters, then skip the next stage. When erecting a structure with layered rafters, you need to think about the supports that are installed on the floor. To reduce the deflection of the rafters, correctly calculate the location of such supports.
10. If you are building a gable mansard roof, the intermediate posts will become the frame for the side walls.
11. When performing this work, maintain a certain pitch of the beams. Set its size at the design stage.
12. After installing the rafters, attach the ridge. It is placed along their upper edge. For fastening use metal corners or staples. And the most popular are bolts.

Rigidizing the structure

After installing the gable roof rafter system, strengthen it using the technology presented below:

• For small buildings, such as saunas, cottages, utility buildings, and roofs with a simple hanging rafter system, connect each pair of rafters from below using a tightening, and from above using a crossbar.
• For large buildings that are also lightweight, choose a light roof. The walls must support it.
• If the house is 6-8 m wide, then the structure should be strengthened. Place the support in the middle. Such racks are called headstocks. Place them at each pair of rafter legs.
• If the span of the walls reaches 10 meters, then reinforcing beams will be needed. The struts act as additional support for the rafter legs for tightening. They are attached to each rafter - closer to the ridge or in the middle of the rafter leg. Fasten them to the lower end of the headstock and to each other, as shown in the video about the gable roof rafter system.
• In situations with long roofs, the gable beams should be relieved. This is done by installing braces. The top end should rest against the corner of the gable. The lower one is mounted on the central floor beam. For fastening, use a beam that has a large cross-section. This way you can prevent them from breaking if there are strong gusts of wind.
• In areas where winds prevail, the rafters must be resistant to such influences. Strengthen them by installing diagonal braces. The boards are nailed from the bottom of one rafter to the middle of the next.
• For greater rigidity, when creating the most critical fastenings, it is better not to use nails. Use pads for this and metal methods fasteners Nails will not be able to provide high-quality fastening, since the wood can dry out after some time.

Lathing of the rafter system

The final stage of installing a gable roof rafter system is the creation of sheathing. It is on this that you will lay the roofing covering. Carry out the work in the following sequence:

1. Select dry timber for sheathing. There should be no cracks or knots on it. Nail the beams from below. Attach two boards near the ridge so that there are no gaps. The sheathing must withstand the weight of the upper roofing material and not bend under the weight of the workers.
2. If you are installing a soft roof, make two layers of sheathing. One is sparse, the second is continuous. The same applies to roll roofing. To begin, place boards parallel to the ridge beam that are 25 mm thick and no more than 140 mm wide. A small gap is allowed - no more than 1 cm. Lay a continuous layer on top. To do this, it is better to use roofing plywood, slats or boards of small thickness. After this, check that there are no errors left on the sheathing - irregularities and knots. Also check that there are no nail heads sticking out.
3. Place one layer of timber under the metal tiles. It should have a cross section of 50 by 60 mm. Proceed in the same way when using slate or steel roofing sheets. Maintain a step between the beams, depending on the roofing you choose - from 10 to 50 cm. Hammer the nails closer to the edges of the board, and not in the middle. Drive the hats in deep. This way they won’t be able to damage the roof later. If you are making sheathing for metal tiles, then remember that the connection of the timber at the same level should fall on the rafter.

When you have installed and strengthened the rafter system of the gable roof, you can begin installing the roofing pie. Place between rafters thermal insulation material, a layer of vapor barrier and waterproofing. When using insulation in slabs, calculate in advance the pitch of the rafters for its installation. At the final stage, attach the roofing material.