Attachment points of the tightening to the rafter leg. Attachment points for the roof truss system. How to connect parts of the rafter system

Rafter system Is the skeleton of the roof. It is she who is responsible for the strength of the roof, its reliability and resistance to loads. At self-construction at home, you need to know how to correctly make the attachment points for the rafter system so that the roof is reliable and safe.

The device of the rafter system

The rafter system consists of many elements, each of which performs its own task.

• Mauerlats are responsible for the distribution of loads on the walls. These beams carry the weight of the entire roof and rest on the walls.
• Rafter legs- these are inclined beams, which create the required angle of inclination of the roof.
• Girders are horizontal beams that hold the legs together. There is a ridge run, located at the top, and side ones, located with the slopes.
• The puffs are located horizontally and do not allow the rafter legs to part, forming rigid triangles with them.
• Racks and struts(rafter legs) - additional elements on which the rafter legs rest. They run into the beds.
• Lezhen - a horizontal beam under the ridge; racks and struts rest on it. The task of the bed is to redistribute the point load from the racks.
• The ridge is the junction of the roof slopes.
• Lathing - bars or boards that are stuffed perpendicular to the rafters. Roofing material is laid on it. The task of the crate is to distribute its weight.
• Overhang - an elongated edge of the slope that protects the walls from precipitation. If the length of the rafter legs is not enough to create an overhang, additional elements are used - filly.

The structure of the rafter system is shown in the figure.

Also, roof trusses are distinguished in the roof structure. This is a solid knot consisting of rafter legs, stretch marks, struts and struts (braces, jibs). The truss can be not only triangular, but also trapezoidal, segmental or polygonal. Which type of farm to choose depends on the size of the house. If the distance between the walls is 9-18 m, then it will do triangular truss... For houses with a width of 12 to 24 m, trapezoidal or segmental trusses are used. If the width of the building is greater (up to 36 m), then polygonal trusses are used.

The main attachment points for the roof truss system are girder, ridge and Mauerlat.

Types of rafter systems

Rafters can be hanging and layered.

Hanging ones rest on the walls and create a spacer. To reduce it, tightens are made at the base of the rafters, which connect the rafters and form triangles with them. Hanging systems of various types are used for houses no more than 17 m wide. Depending on the width of the building, they are arranged in different ways.

If the width of the house is not more than 9 m, then the rafters are supported by a vertical bar - the so-called headstock. She is under the ridge.

If the width of the house is from 9 to 13 m, struts are additionally installed, which with one end abut against the rafter legs, and the other against the headstock.

With a house width of 13-17 m, two vertical posts, connected at the top with a crossbar (fitting), as in the figure.

Reinforced rafters rest on a load-bearing wall or columns inside the building. With this method, the rafter has three or more points of support. The rafter type of rafter system creates less stress on the walls of the building and is more durable; it is used for buildings of greater width. Such roofs can be arranged in different ways, depending on the location of the internal walls, they can be symmetrical or asymmetrical.

How to connect parts of the rafter system

To connect wooden elements with each other, nails, bolts, pins, as well as metal plates and corners are used to strengthen the nodes. Additionally applied wooden blocks or plate.

Fastening methods:

• teeth into a thorn,
• teeth point-blank,
• stop at the end of the crossbar.

The use of metal fasteners does not reduce the bearing capacity, since they do not need to be cut in, in contrast to fastening, for example, by the method of teeth in a tenon.

Rafters can be not only wooden, but also metal. For fastening metal rafters use various corners, brackets, perforated mounting tape, plates, bolts with nuts or self-tapping screws.

Mount to Mauerlat

If the wall is concrete, then in its upper part they make reinforced belt stiffness in which studs are provided. The Mauerlat will be attached to them.

Rafters to the Mauerlat can be attached in two ways: rigid and sliding.

The first method is more popular. For fastening, special corners with a support bar are used. There are several ways to attach the rafters to the Mauerlat.

• Each rafter is nailed with three nails: two of them must be crossed, and the third is located vertically.
• Fastening with a bracket: one end of it is hammered into approximately the middle of the support bar, and the other is turned 90 degrees and hammered into the rafter.
• Fastening with wire rod: a clamp is made from a wire folded in 4 rows, with which the rafter is screwed to the bar. Instead of wire, a special perforated tape is also used. Sometimes this method is used in addition to other fastening methods.
• Using corners: the corner is screwed to the Mauerlat and rafter leg... It is better to use corners with two rows of holes and a stiffener.

The disadvantage of a rigid method is that when the building subsides, the walls may be damaged. So rigid mount used in brick buildings.

The sliding method implies that the rafters are connected to the Mauerlat with such fasteners that do not impede their movement within certain limits. This method is used in wooden buildings that can sink. With the help of special fastening methods, it is possible to achieve that the rafter will have one, two or three degrees of freedom. In the latter case, a special hinge is used.

One degree of freedom implies that the rafter can rotate in a circle. In this case, they are fastened with one nail or screw. The two degrees of freedom are circular rotation and horizontal offset. For this, the rafters are attached to the Mauerlat with metal brackets. Special skid angles are also used.

With a sliding joint in small buildings with a not very heavy roof, the fastening is done without cuts. If the building is large, it is recommended to make this knot with a saw cut on the rafter leg.

Important! The saw cut is cut precisely on the rafter, and not on the Mauerlat, so as not to damage or weaken the beam.

In this case, fixation can be either rigid (with an emphasis on the beam), and movable (with a tooth on outside). Sometimes, instead of sawing out the tooth, an additional bar is used.

Ridge connection

After the rafter leg is attached to the Mauerlat, they go to the ridge attachment point. This connection can be made in three ways: end-to-end, to ridge girder and overlap.

For end-to-end fastening, the rafters are cut in the upper part at an angle equal to the slope of the roof, and connected with nails (150 mm), driving them into the upper planes of the rafters, so that the nails enter the end of the opposite rafter. Attach for strength metal plate or a piece of wood, which is also nailed or bolted.

When attached to a ridge girder, a ridge beam (girder) is additionally laid between the rafters, this method is more laborious.

When overlapping, the rafters located on opposite sides go over each other and touch with their lateral surfaces. They are connected with bolts, nails or studs.

Beam node

The rafters are attached to the beams as follows. The main task of fastening is to prevent the rafters from sliding along the beam, therefore various techniques are used.

1. In the heel of the rafter, it is necessary to cut out a tooth and a spike, and a stop of the appropriate size is cut out in the beam.
2. The attachment point should be 25-40 cm away from the hanging edge of the beam.
3. The mounting socket should be 1/4 to 1/3 deep of the beam thickness.
4. Together with the tooth, a spike is cut out, which does not allow the rafter to move sideways. Such a connection is called a "spike and stop" tooth.

If the roof is flatter (its angle of inclination is less than 35 degrees), then the rafters are fixed in such a way that the area of ​​their contact with the beam increases. Then use the following methods:

When creating a roof rafter system, it is important to remember the following.

• Before installation, all wooden elements are treated with an antiseptic and a refractory compound.
• The thickness of any wooden part should not be less than 5 cm.
• Rafters without racks and struts are not made longer than 4.5 m.
• Mauerlat should be placed strictly horizontally.
• Racks and struts are recommended to be done as symmetrically as possible.
• You cannot add elements to the calculated rafter system - this can lead to the appearance of loads where they are not needed.
• At the junction of wood with stone (brick) masonry, waterproofing is needed.

A properly made rafter system is the key to the reliability of the roof. It is the rafters that bear the entire weight of the roofing materials and withstand wind loads. Therefore, it is very important to build a rafter system in compliance with the technology.

A pitched roof of a house consists of a large number of parts, each of which is connected to others in a special way. This connection is called a roof node. In this article, we will talk specifically about the connection nodes, how it is carried out, what technologies are used, what fasteners are used.

The main parts of the roof structure

Before proceeding directly to the analysis of the topic of the article, it is necessary to indicate which elements (parts) the roofing structure consists of. We list all the main details and designate their purpose.

Mauerlat... This is a beam that is laid on the walls of the house, located along the perimeter of the building. The purpose of the Mauerlat is to evenly distribute the loads emanating from the rafter system. After all, if there is no Mauerlat, then each rafter will press on the wall pointwise. And it is in this place that the destruction of the wall structure will occur.

Rafter legs... They are made either from boards with a thickness of at least 50 mm, or from beams. The rafters are the basis of the roof, it is they who form the slopes and bear all the loads acting on the roofing structure.

Ridge run... This is the topmost beam, installed horizontally. Its purpose is to support the upper ends of the rafter legs. It is he who forms the ridge of the roof.

These are the three main elements of the roof, which will be discussed further. Of course, these are not all the details of the roof, and one cannot say that others are less important. It's just that these three elements form the structure itself. The only thing to add is that some roof structures do not have a ridge girder. It's just that the upper ends of the rafters rest against each other. This type of rafter is called hanging, and with ridge run layered.

So that the roof structure is the most reliable, it is necessary that the nodes of the roof are connected correctly. In this case, the force of the acting loads and their direction must be taken into account.

How to connect elements of the roof structure

More recently joining the nodes of a wooden roof carried out with the help of cuts. That is, the elements were cropped roof structure to connect them on one wide enough plane. Therefore, so that the roof parts do not reduce their strength characteristics, as well as bearing capacity, they were selected with a sufficiently large cross section. And this is not economical. That is, the larger the cross-section of the lumber, the more expensive it costs.

Today, the technology of fastening nodes and parts of the roofing structure has changed dramatically. To do this, use bolts, pins or metal perforated profiles. The latter are made of galvanized steel, which makes it possible to operate fasteners for a long time without losing their quality. At the same time, manufacturers offer a fairly wide range of them for each type of assembly. The photo below shows some of these fasteners.

It should be noted that perforated profiles gradually replaced all other types of fasteners due to the strength, reliability and ease of fastening operations. After all, for this you just need to install the profile in the required place and fix it to various parts with wood screws or ruff nails.

Let's now see how it should be fix parts the roof structure between each other. In principle, there are two types of connection: mauerlat-rafters, rafters-ridge girder. The rest of the parts are connected parallel to these joints. He will also talk about them.

Mauerlat and rafters connection

There are actually a huge number of fastening options, from ordinary nails to perforated profiles. For example, the photo below shows an option where ordinary wire is used as fasteners. That is, a through hole is made in the rafter itself, where a wire with a diameter of 6 mm is inserted. A hole is made in the Mauerlat or in the ceiling beam.

Then the ends of the wire are pushed into this hole and twisted, pressing the rafter leg against the Mauerlat. The connection is actually strong and reliable, but the process is laborious.

Instead of wire, you can use metal tape 3 mm thick. It is simply wrapped around two connected elements and through a strip they are attached to them with self-tapping screws, more often with nails. In the latter case, there is no need to drill through holes in the metal. note that in the lower photo the fastening is carried out to the reinforced belt with an anchor, which increases the strength and reliability of the connection.

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The next type of fastening is a perforated galvanized steel corner. The most convenient option, but the most reliable. To do this, the corner is simply installed so that it presses tightly against the plane of the Mauerlat and the rafter leg with its mounting shelves. Fastening is carried out with screws or nails.

Fasten corners it is possible not only with self-tapping screws or ruff nails. There is another more reliable option where bolts are used. True, holes will have to be made for them, which increases the costly time for carrying out this type of work. But in this case, quality is paramount. In the photo below, just such a mounting option is shown. Please note that the corner is attached to the Mauerlat with self-tapping screws, and to the rafter leg with a bolt. In this case, one bolt is used to connect two angles located at opposite ends of the rafters.

And one more mounting option - on the slider... This is a special kind fastener, consisting of two parts. One is attached to the Mauerlat, the second to the rafter leg. In this case, both parts are not tightly connected to each other. This is done specifically so that the rafters can move relative to the Mauerlat during the thermal expansion of the lumber. This means that there will be no loads that act on the joint of two roof parts. The photo below shows this connection option.

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Connecting rafters with a ridge girder

The second main node of the wooden roof is the joint between the rafter leg and the ridge bar... In fact, the ridge knot of the rafter roof is very complicated, because two rafter legs and a beam are joined on it. Moreover, all elements are located in different planes, meaning rafters and beams. This means that more than one fastening element will have to be used to connect them.

To connect the rafters to each other, use perforated plate... There are two of them, installed on different sides of the rafter legs to increase strength and reliability.

Perforated corners connecting the rafters to the Mauerlat. There are four of them, two for each rafter leg, installed on different sides.

It should be noted that fastenings can be carried out not only with self-tapping screws or nails. Often, masters use bolts for connection paired fasteners.

Pay attention to the different type of fastening. Only corners are used here. This option is used if a board with a thickness of 50 mm is installed as a ridge bar.

Another interesting option fastening the rafter legs to the ridge span, for which they use special perforated complex shaped profiles... In fact, these are brackets into which the rafter leg is inserted. The bracket not only holds the parts together, it supports the rafter, reducing the stress on its end.

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Pay attention to all of the above options for connecting the rafters to each other. They clearly show that the ends of the rafter legs are joined tightly to each other, for which they have to be filed at a certain angle. You can do without filing if you use a complex fastening lock consisting of several plates that are bolted together. In the photo below, this connection option is clearly visible.

Hanging rafter connection

The rafter system of this type differs from the layered one in that it does not ridge run... That is, the rafter legs in the upper part (ridge) abut against each other. So that they do not leave for different sides, the rafters are connected to each other by horizontal tightening. The latter is a board located at any distance in height: top, bottom or in the middle.

It should be noted that hanging rafters on the roof separately are not assembled. Of these, farms are assembled on the ground, which, in finished form, are installed on the roof of the house. In this case, all elements of the truss are interconnected with perforated plates.

Video description

In the video, the master tells how to assemble a truss truss using perforated plates and nails:

Other types of nodes

As mentioned above, there are many details in the roofing structure. Therefore, we will tell and show a few more important connection nodes.

If the span of the house is more than 6 m, then a rack is installed under each rafter, which itself should rest against either a concrete base or a floor beam. In this case, the connection of the rack with the rafter leg is carried out ordinary boards as shown in the photo below. Although perforated metal plates can be used.

A ridge bar is also installed vertical support posts, which are fastened together with perforated plates. But some roof structures use a completely different approach to solving the installation of a ridge girder. Jibs made of bars are mounted under the timber, which are fixed to the ridge with special fasteners made of metal. The photo below shows one of the options for this type of fastener.

Very often, when constructing a rafter system, it becomes necessary to lengthen the rafters themselves. It is not difficult to do this, while the craftsmen use several technologies, where they use various additional fasteners.

Video description

The video shows one of the options for lengthening the rafters:

Roofing structures are several varieties of their shapes. Almost all models have a large number of the same elements. But there is one design among them, which differs significantly from the others. This hipped roof ... Its distinctive feature is that the rafters are connected top edges at one point, which is called the ridge knot.

So, in order to connect the rafter legs to each other, you need a support to which they are attached. There are several ways to ensure high reliability of the node. The photo below shows one of them, which uses perforated fastening metal profiles U-shaped.

Conclusion on the topic

In fact, we have considered only a small part of the connecting nodes for fastening the roof truss system. But even on their example, the variety of parts and assemblies becomes clear. That is, the roofing structure is a complex system, consisting of a large number of different elements and parts that are interconnected in different ways.

In order for the roof to have high strength and reliability, you will need to pay special attention to the rafter system. In addition to correctly made calculations and drawings, fasteners for rafters and all its elements are of no small importance in the stability of the structure.

The structure of the rafter system.

In addition to the load of atmospheric precipitation, the rafters must withstand the weight of the sheathing and the total weight of the roofing cake, which must be taken into account when selecting the fastening.

A rafter system is a spatial structure consisting of the following elements:

In order to understand how all parts of the rafter system are attached to each other, you need to figure out what nodes it consists of, what fasteners are used in each case and what they are. When assembling the supporting structure of the roof, fasteners are used, both steel and wood.

The main joints of the rafter system

Mauerlat fixing scheme to the wall.

Before connecting the Mauerlat and the rafter leg together, the first will need to be firmly connected to the wall. Mauerlat is a thick beam (15x15), laid along the axis of the wall and parallel to the ridge of the beam, on which the rafter legs rest. The functions assigned to this element of the supporting structure are to distribute the load from the rafters, the weight of the roofing cake and atmospheric precipitation throughout the entire wall, including the internal supports. In other words, the Mauerlat is the foundation for the entire roof. It is laid on the axis of the wall and fixed to it. In this case, there are several connection methods.

Method one. When installing a roof of a large area along the entire length of the wall, an armored belt is poured, where metal pins are immediately embedded under the M12 thread every 2 m.In this method, as a fastener for the Mauerlat with the wall, there will be pins that go through the beam and are attracted to the wall with a nut and washers. With a small roof area, where there is no large load on the wall, a Mauerlat is dispensed with and the rafters are attached directly to the studs embedded in the masonry process.

Method two. Another quite affordable way to make the rafter system stable is to attach the Mauerlat to the wall with wire. To do this, you will need to lay the middle of the wire between the rows of bricks 3 rows before the end of the masonry. Its length should be sufficient to tie and pull the Mauerlat to the wall. You can also do without the Mauerlat and fix the rafter with wire directly to the wall. But such a connection will give a point load on the wall, which can affect its integrity.

The scheme for attaching the rafter leg to the Mauerlat can be rigid and sliding. The type of connection depends on the shape of the roof and the type of rafters, which can be hanging or layered.

Rigid and sliding connection of the lower part of the rafters with the Mauerlat

The main nodes of roof trusses.

The connection nodes in this case will be made of wood and can have several types:

1. A tooth that has only an emphasis.
2. A tooth that has a thorn and an emphasis.
3. Stop directly on the beam.

The single tooth cut is used for roofs with a large angle of inclination, where the angle between the Mauerlat and the rafter leg is more than 35º. To do this, in the rafter leg, you will need to cut a tooth with a spike, and create a nest for it in the Mauerlat. The use of a tenon avoids lateral displacement of the rafter. The double-tooth cut is used for the installation of shallower roofs. The latter method is rarely used.

Recently, more and more often wooden mount for rafters is replaced by metal, since it allows not only to get more reliable design rafter system, but also significantly reduce the work on its installation. Therefore, metal rafter bolts, brackets, plates, clamps, hinges and various corners are used as additional fasteners.

An example of a rolling join ..

The most used rigid connection method is to drive nails from the sides at an angle into the Mauerlat. Thus, internal crossing occurs within it. Further, for the final fixation of the connection, a third nail is driven vertically. Another way to prevent lateral displacement of the rafter leg is to secure it on the sides with metal corners.

The scheme for movable fasteners of rafters in the lower part is used for houses built from rounded logs or beams. Since during operation, the rafter system is in motion due to changes in its physical properties, that is, the building shrinks.

A rigid fastening scheme in this case is unacceptable, since such movements can lead to the destruction of the wall. This means that the attachment points need to be mobile. In such cases, special hinge joints are used, which are called sleds or corners with an oblong hole for fasteners. The sliding interface in this fastener achieves two levels of freedom by free movement of one of the fastener elements.

Nodal ridge connection

The ridge connection of the rafter system can be obtained in three ways: end-to-end, overlap and on the ridge beam.

Diagram of the ridge connection of the rafter system.

Butt. The upper part of the rafter leg must be cut at an angle equal to the slope of the roof. The opposite leg is also adjusted to the appropriate angle, but with an inclination to the other side. Further, they are connected to each other at the top point with the help of a nail, which must be hammered into the end of the rafters with the capture of the opposite end. In addition to nails, special plates are used for a more durable connection of joints. Both a 30 mm wooden board and a metal fixing double-sided plate can act as such a fastener. Bolts or nails are used to install it.

The next two methods will be similar to the first, but have a slight difference. When fastening with an overlap, the upper parts of the rafter leg will be connected to each other by their lateral sides. The latter option is carried out by connecting each rafter directly to the ridge beam. In this case, threaded rods with washers and bolts are used as fasteners.

If trusses are used to stiffen the rafter system, then in order to ensure good resistance to wind loads, it will be necessary to install required amount diagonal ligaments. The presence of a brace and a brace (rafter leg) in the supporting structure helps the gables of the house to be more stable. The brace is installed by resting the upper part against the corner of the pediment, and with the lower part it abuts against the main floor beam. The brace helps to reduce the load on the rafters in the center. Its installation is carried out at an angle of 45º. Diagonal ties are fixed using clamps, corners, plates.

Types and features of metal fasteners for rafters

If earlier craftsmen used wooden elements as such fasteners (bars, pads, pins, metal staples, wooden pins, wedges), now such methods are inferior to more modern types. The construction market has a large range of metal fasteners, which are now much stronger and make the installation process of the rafter system much easier. In the technology of manufacturing these elements, metal is used, the thickness of which varies from 1.5 ... 3.0 mm, which allows the product to be more resistant to stress in comparison with any other material. In addition, rafter fasteners are available in any size and allow you to carry out the technological process with great precision.

Types of fasteners for rafters.

Metal fasteners for rafters, which can be perforated and nailed, include:

• perforated mounting tape;
• corners;
• plates;
• beam support;
• support of the bar;
• wire tie;
• self-tapping screws;
• bolts with nuts;
• corners of the Kyrgyz Republic;
• brackets WB;
• fasteners LK.

The use of perforated products allows you to firmly fasten the rafters with all parts of the system and provide good rigidity and strength at any angle. They are characterized by the presence of many holes for bolts, screws and self-tapping screws, with the help of which fastening to the tree is carried out. The size of the product is adjusted by cutting to the desired length and width.

Also, fasteners can be nails. However, the use of this type is possible only in the factory by the punching method, which bends the tapered part. This operation is carried out with special pressure machines.

KR corners have a large number of modified types that reduce the risk of breaking the bolted connection during natural settlement of the structure. Fastening is carried out without the use of special equipment using screws and nails.

WB brackets are used to attach the console load-bearing beam when arranging wooden floors in houses from rounded logs or beams. In this case, the insert on the rafter leg is not made, which does not weaken its bearing capacity. The connection is made using anchor bolts, nails or screws.

The LK rafter fastener is applicable in a rafter system where it is required to connect rafters and beams. It has the same advantages as the WB fastener, but the process is carried out only with screws or nails. Used in construction wooden houses.

Fasteners in the rafter system play a huge role. It is on him that the strength and durability of the entire roofing cake depend. Therefore, the choice of the type and method of fastening should be treated with great care.

Fasteners for rafters: strength and reliability of the roof

In order for the roof to have high strength, fasteners for the rafters require special attention. The type of connection will depend on the shape of the roof and the type of rafter system.

Fastening the rafters to the Mauerlat: connection methods

Rafters are the main load-bearing structural elements of the roof. Correct and reliable fastening of the rafters to the Mauerlat eliminates the risk of deformation and collapse of the roof under its own weight and external loads.

Basic fasteners

To install the rafter legs on the Mauerlat and firmly fix them, various types of cuttings (cutouts) and metal rafter fasteners are used:

• wire ties;
• corners;
• plates;
• brackets WB;
• corner of the Kyrgyz Republic;
• fasteners LK;
• self-tapping screws;
• nails;
• perforated assembly room for summer TM;
• bolts, studs complete with nuts and washers.

The connection of rafters and Mauerlat can be done using brackets. In this case, a tie-in is not made in the rafter, thus this key element the structure is not weakened. Mounting brackets are made of 0.2 mm steel with anti-corrosion zinc coating. Brackets are attached to a wooden beam and a rafter with self-tapping screws, nails or anchor bolts.

Fasteners LK allow you to attach the rafter to the Mauerlat, as well as connect other elements of the system. Anchor bolts are not used when installing this fastener.

The use of perforated mounting tape allows you to strengthen the connection unit... The perforated tape makes the connection of the rafters with the Mauerlat more durable, does not weaken the supporting structures, since it does not violate their integrity. To install it, you need screws or nails.

The KR corner and its modifications are a widely demanded fastener for the truss system. It is used when it is necessary to securely install the rafter legs on the Mauerlat. The corner adds strength to the joints, increases the load-bearing characteristics of the structure, and eliminates the displacement of the rafters under high operating loads. The corner does not need to be cut into the wooden elements of the rafter system; it is mounted with self-tapping screws or with brushed nails (equipped with special projections).

Metal fasteners for the truss system must be made of high-quality material with reliable corrosion protection - this guarantees its strength and durability.

When is a Mauerlat required?

Mauerlat is often called the foundation of the roof. This structure, made of a log or a bar, allows not only to securely fasten the rafters, but also to ensure uniform load transfer to the walls and foundation of the structure.

When building houses from a bar or log, it plays the role of a support for rafters top rail walls, installation of additional structures is not required.

For structures whose walls are made of piece materials (brick, foam concrete or aerated concrete blocks, etc.), the installation of a Mauerlat is necessary. This is due to the fact that walls of this type do not cope well with point, non-distributed loads. In addition, foam blocks are not strong enough to securely hold the rafter system - fasteners can be pulled out of the block under load. Thus, the installation of the Mauerlat is required.

To wooden bar, laid on the longitudinal walls of the building or along the entire perimeter (depending on the type of roof) was firmly attached to the base, it is recommended to pre-create a reinforced concrete belt in the upper part of the walls. In a monolithic beam with a height of 200 mm and a width that coincides with the width of the wall, fasteners for the support bar are embedded. These are anchor bolts or studs with a diameter of 14 mm, located strictly vertically. Bend the lower ends of the studs or bolts to prevent them from being pulled out of the concrete under high stress. The embedded fasteners are located in increments of no more than 1.5 m.

The use of studs with a diameter of less than 14 mm can lead to deformation of the fastener under load.

In the bar from which the Mauerlat is mounted, holes should be made corresponding to the location of the studs. The bar is put on the studs, washers are put on the free threaded end of the fastener and the nuts are screwed on. This technology allows the roof base to be securely fixed to the wall.

Before installing the timber, it is required to lay a waterproofing layer in order to prevent damage to the wood due to moisture.

Principles of attaching rafters to Mauerlat

Installation of rafters on a support bar may be required when creating spacer and non-spacer rafter structures. Installation of layered or hanging rafters on the Mauerlat is performed using a rigid or sliding connection. Depending on the design features, methods of attaching the rafters to the Mauerlat are selected.

Rigid connection implies the complete elimination of displacement of elements relative to each other, the absence of such influences as shear, torsion, bending. The required rigidity of the connection is ensured if the rafters are attached to the Mauerlat with corners with a support bar, or a special “saddle” cut is made in the rafter leg. The place of the cutout in the rafter is additionally secured with self-tapping screws, nails, brackets, bolts. In addition, it is necessary to perform a wire twist, which connects the rafter attachment point with the Mauerlat and the anchor mounted in the wall.

When constructing roofs of wooden houses, a special fastening element ("skids") is used, which allows a sliding connection. The attachment point of the rafters to the Mauerlat with a certain degree of freedom of the rafters makes it possible to avoid deformation of the roof when the house shrinks from a bar or log.

Installation of rafters using a corner

When choosing how to attach the rafters to the Mauerlat, it is necessary to proceed from the design features of the roof. If it comes not about wooden buildings, then the joint must be rigid.

If the installation of the rafters is carried out with a "saddle" cut, then the technology of work is as follows:

• a cutout is made in the rafter leg in such a way that the horizontal part of the rafter can be installed on a wooden beam, while the angle of inclination of the rafter leg must correspond to the angle of inclination of the slope;
• The rafters are fixed with three nails, two of which are driven in on both sides of the rafter leg at an angle (crossing must occur inside the Mauerlat), and the third nail is driven vertically from above;
• additionally, the attachment point is fixed with brackets, wire rod.

Such fastening of the rafters to the Mauerlat provides the necessary rigidity and strength of the knot.

A fairly common technology is the installation of rafters using a metal corner and a hem. The rafters are attached as follows:

• the rafter leg is cut at the required angle to ensure the slope of the roof slope specified by the project;
• along the edge of the Mauerlat, a hemming beam is mounted, the length of which is about 1 meter, the rafter firmly rests against it along the pressure line - this design eliminates the shift of the rafter leg under loads on the spacer;
• on the sides, the rafter should be attached to the Mauerlat using metal corners - fastening the rafters to the Mauerlat with these elements makes it possible to avoid lateral displacement of the rafter leg;
• the finished attachment point is additionally reinforced with wire rod.

Fastening the rafters to the Mauerlat should be carried out following the instructions; the details of the work technology can be found in the video.

The rafters are attached to the wooden support beam using special corners. The subspecies of the corner of the Kyrgyz Republic include:

• models KR11 and 21 (improved KR1 and KR2) are equipped with oval holes for anchoring, which can significantly reduce the risk of breakage of the fastening element during settlement of the building or load of the structure;
• the KR5 model allows you to fasten structural elements with a high bearing capacity;
• model KP 6 (reinforced corner) is made of steel 3 mm, has an oval hole for anchoring, it is used for mounting structures with a large weight.

Bearing and auxiliary elements of a wooden roof structure They are also fastened using the KM mounting angle made of perforated steel. Its advantages include the possibility of fastening with self-tapping screws and screws, the absence of the need to use special equipment for installation.

Reinforced angle KMRP is used for 90 ° connections. Its use allows you to reliably install wooden rafters on the support bar. The corner can be adjusted.

Correct fixation of the rafter legs on the Mauerlat is the key to the durability and reliability of the roof structure. The scheme of attaching the rafters to the Mauerlat may be different, but there are general rules mounting:

• it is important to ensure a tight fit of the planes of wooden elements, which requires accurate and precise execution of cuts and cuts;
• using bolted joints, it is necessary to install washers or metal plates in order to avoid sinking the nut into the wood - this can lead to the destruction of the fastener.

The use of linings is prohibited, since over time they deform, which leads to an incorrect distribution of loads on the roof and entails a deterioration performance characteristics, destruction.

Fastening the rafters to the Mauerlat: how to fasten, attachment point, methods

Find out how to attach the rafters to the Mauerlat. Types and methods of connecting rafters, a diagram of fasteners for the Mauerlat and rafters, along with a video.

How to choose the right fasteners for mounting the rafter system

The frame of the rafter system and the foundation of any roof is the Mauerlat. V wooden houses its functions can be performed by the upper crown of a log house, and a powerful base of timber is mounted on brick and concrete walls.

Mauerlat mount

1. In houses built of laminated veneer lumber or logs, Mauerlat is not required. If the height of the bearing walls is not enough, an additional Mauerlat crown is laid. For its fastening, forged brackets and steel pins (spikes) are used.

2. Mounting the Mauerlat on brick walls is possible in several ways:

- in the process of laying the bearing walls to a depth of 3 or more upper rows of bricks, studs with a diameter of at least 14 mm are walled up. The lower end of the stud should be bent at right angles to form a “L”. The length of the free part of the hairpin should be 3-4 cm more than the thickness of the Mauerlat;

- at the final stage of laying the bearing walls, a reinforced belt is poured. "L" -shaped pins or anchor bolts with a diameter of at least 14 mm are embedded in it. The length of the open part of the fasteners should exceed the thickness of the Mauerlat by 3-4 cm.

The distance between the studs (anchor bolts) is chosen as a multiple of the rafter pitch and is equal to 1.0. 1.5 m.

Before installing the Mauerlat on stone walls a layer of waterproofing material must be laid.

Fastening the rafters

1. Houses made of logs or beams shrink during operation, and their geometric parameters change. In such conditions, the roof must have some independence. With a rigid attachment of the rafter system, the roof wooden house bends, and roofing materials are destroyed. In the worst case, this can lead to the destruction of the frame of the house, so the rafter joints are made mobile.

Rafters in the ridge can be attached in two ways:

- movable connection with M16 bolt;

- connection by means of a plate hinge. In this case, on each rafter with 4 M10 bolts. M12 fastened by two steel plates. The role of the hinge is performed by the M16 bolt.

Fastening the rafters to the Mauerlat is carried out using the so-called "sled". The bracket and bracket are fastened with nails, while the rafter has the ability to move slightly relative to the Mauerlat along its longitudinal axis.

2. If the house is made of bricks or cinder blocks, a rigid fastening of the rafters is used. In this case, the ridge connection is made in the following ways:

- fixed butt joint. In this case, the rafters are fastened with nails, and the entire unit is reinforced with additional steel or wooden overlay- crossbar. The crossbar is attached to the rafters with M10 bolts. M12 or nails, respectively;

- a fixed connection with a cut-in half-tree. In this case, the rafters are connected with an M16 bolt, and the assembly is reinforced with a crossbar.

The rafters are attached to the Mauerlat using reinforced steel corners. M10 bolts are used to fix the corners. M12 and nails.

Clamps, wire ties and perforated mounting tape are used as additional fasteners for fixed units.

Everything threaded connections performed using metal washers or plates.

When fastening structural parts with nails, it is necessary to adhere to the following rule: the length of the nail should be 2-3 times the thickness of the pierced element.

How to choose the right fasteners for mounting the rafter system

For novice craftsmen who are building a house with their own hands, the rafter system is perhaps the most complex design. The largest number questions are raised by the ways of fastening individual elements and the fasteners used. The stability and durability of the roof largely depends on these nodes, so let's talk about them in more detail.

Fastening the rafters to the Mauerlat

The reliability of the roof structure directly depends on how correctly its entire supporting system will be mounted. And its main elements are the rafters. The entire system consists of rafter legs that support and expand additional elements, such as struts, braces, crossbars, side girders, support posts and braces. The rafter legs are connected on the ridge beam from above, and their lower edges very often rest on the Mauerlat, fixed on the side load-bearing walls of the building.

Fastening the rafters to the Mauerlat

Since the greatest load falls on the Mauerlat, it is made from a powerful bar. Its cross section is determined by the massiveness of the entire rafter system, but basically the size is from 150 × 150 to 200 × 200 mm. This load-bearing element is designed to evenly distribute the load from the entire roof structure and roof onto load-bearing walls buildings. The rafters are attached to the Mauerlat in various ways. They are selected locally, depending on the type of rafter system (which can be layered or suspended), its complexity and massiveness, and the magnitude of the total loads to which the entire roof structure will be subjected.

Varieties of "rafters - Mauerlat" connectors

First of all, there are sliding and rigid rafters to the Mauerlat.

1. Sliding mounts consist of two separate elements, one of which can be moved relative to the other.

These mounts can be of different design - closed and removable.

Closed sliding mount

• The closed mount consists of a corner, which is attached on one side to the Mauerlat, and on the other side has a special slotted eyelet. A metal loop with holes for fastening to the rafters is installed in it. Thanks to the free, not fixed vertical side of the corner, the fastening allows the rafter to move slightly if necessary, exerting a deforming effect on the walls of the building.

Open type movable sliding mount

• The open fastening is arranged according to the same principle, and differs only in that the metal loop is not inserted into the eyelet, but simply the upper part of the vertical shelf of the corner is folded down after installation, thereby fixing the connection.

Video: an example of installing a movable mount on a rafter leg and a Mauerlat

2. There are many more types of rigid mounts. They are selected depending on the massiveness of the wooden structural elements and the method of installing the rafters on the Mauerlat.

Various rigid mountings

This includes metal corners of various sizes, LK fasteners, which will securely fix the rafter installed with a saw, without damaging it with fastening screws or nails.

• LK mounts are produced in several sizes, so they can be matched to any thickness of the bar or board. The thickness of the metal from which these fasteners are made is 2 mm, whatever size they are. Depending on the size, fasteners have a different designation.

It should be noted that these fasteners are suitable not only for connecting rafters on the Mauerlat - they are also used to fix the "floor beams - Mauerlat" nodes.

LK mounts in business

The main advantage of this fastener is the maximum rigidity and reliability of the connection of wooden elements.

• The fastening of the sawed rafters to the Mauerlat with the help of corners is carried out on both sides, which provides the required rigidity.

Corner with reinforced bending stiffener

There are corners designed for fastening rafters without cuts. They have higher shelves and are screwed with a large number of self-tapping screws. They are made from metal with a thickness of 2; 2.5 or 3 mm.

Fastening the rafters to the Mauerlat with corners

KP 11 and KR21 are improved corners, often marked as K P1 and KP2. These elements have an oval-shaped anchorage hole that reduces the risk of bolt shearing in the event of structural shrinkage.

Corners series KR

KP5 and KR6 are corners used for fastening elements that bear a large bearing load. The corner to K P6 is also equipped with oval hole, and it is recommended to use it when creating a rafter system on a new house, which will still shrink. These models are in demand when installing structures that are heavy.

The corner to K M is made of perforated steel and is used for fastening rafters with a large cross-section. It is especially suitable for wooden buildings... This corner fixes the structural elements very reliably, and when using it, you do not need to insert the rafters into the Mauerlat - it is enough to cut the correct corner at the first.

Reinforced corner KMRP series

Corner KMRP is used to fasten the parts of the rafter system at a right angle, including rafters with a Mauerlat. It also differs from conventional corners in its elongated hole, which allows shrinkage displacement without damaging the fastening bolt. It can be used in a design where you cannot tie-in one element to another.

KMRP corners are produced from steel with a thickness of 2 mm. Available in three varieties:

• Another option for fixing the rafters to the Mauerlat is to install them between two boards, sawn at a certain angle, and additionally at the bottom, fixed with metal corners or LK fasteners.

Fastening the rafters between two plank strips

Such fastening of the rafters gives good rigidity and reliability. This method is well suited in cases where the rafter needs to be fixed at the desired angle by lifting it above the horizontal plane of the Mauerlat, but fixing it to the vertical outer side.

• The method of attaching the rafters to the Mauerlat, made of a bar is not too large section... It is carried out by strengthening the bar with wooden linings of the required thickness.

Fastening with a reinforcing pad

Sections of boards are attached to the Mauerlat with nails or self-tapping screws, in those places where the rafter legs will be installed.

In this case, cutouts of the desired configuration and depth are made in the rafters. The rafter legs are securely fixed to the wall using steel wire, which is fixed to a hammered steel crutch.

Fixation with wire strand

• In addition to the above-described fastening methods, the rafters are nailed to the Mauerlat using staples. It should be noted that this method is quite widespread and has been used for a very long time. With the correct fastening of these elements, the rafter system will last for many years.

Fastening the old-fashioned way - with staples

Staples may have different size, are driven in at different junction points.

• Another fastener that is used as an auxiliary is the perforated tape TM. It is used to strengthen the fastener if additional fixation is required.

Perforated metal tape often comes to the rescue.

In some cases, this element can be indispensable, so it also cannot be excluded when installing the rafter legs on the Mauerlat.

Features of roof systems

The rafter system is selected depending on the location of the bearing walls of the building. Each of the systems has its own additional retaining or tightening elements.

Varieties of rafter systems

Rafters

A system with layered rafters differs in that it has one or more anchor points, in addition to the load-bearing walls. In this regard, a significant part of the load is removed from the side walls.

Reinforced rafters supported by a capital partition

In the form of additional supporting elements, side racks and "headstock" are used, which support the ridge and are attached to the floor beams. And the beams themselves, in turn, simultaneously serve as braces for the structure, and also facilitate the load from the rafter system on the load-bearing walls.

Rafters with sliding mounts

Rafters are attached to the Mauerlat most often with sliding joints that can move when the walls shrink or deform, leaving the roof structure intact. This is especially important to take into account in new buildings, since any recently built building necessarily shrinks under the influence of temperature fluctuations and ground movements.

Hanging rafters

Hanging rafters are called due to the fact that they have no other supports besides the two side load-bearing walls. It turns out that they seem to hang over the inner space of the building. In this case, the entire load from the roof frame structure falls on the Mauerlat.

Rafters in a hanging type system

For attaching hanging rafters to the Mauerlat, rigid mounts are used with no degree of freedom of movement, since frame structure has only two points of support.

To remove part of the load from the walls of the building, such additional elements as struts, "headstock" and puffs-crossbars are used, which pull the system to the ridge bar and evenly distribute the load on all walls. The crossbars are installed parallel to the floor beams and pull the rafters together. Without these additional parts, the design can become unreliable.

Calculation of the installation of rafters

In order for the rafter system to be reliable and durable, in addition to the optimal connection method, you need to choose the correct pitch of the rafter legs. This parameter is selected depending on the dimensions of the rafters (their section and length between the support points), as well as on the roof structure.

In this table, you can get information on the necessary parameters for the installation of a reliable rafter system.

Several rules for attaching rafters to the Mauerlat

In order for the fasteners to be reliable, it is necessary to follow a number of rules that are provided for this process:

• If metal fasteners are used for fastening, then they must be fastened to the wooden connecting elements with the utmost care - high-quality self-tapping screws the desired length.
• If the rafters fit into the cuts in the Mauerlat, then the dimensions must be precisely verified. This will ensure a tight, reliable installation of the rafters in the prepared cut, which should have a depth of ⅓ of the Mauerlat. However, it should be remembered that such a rule will be true only if the Mauerlat is made of a powerful bar with a cross-sectional size of at least 150 × 150 mm.

Gash on the Mauerlat

• In order not to weaken the Mauerlat, most often the cuts are performed in the rafter leg itself at the desired angle, and in addition the knot is then fixed with corners. In this case, the cut should not exceed ¼ of the rafter thickness. This mount is rigid and can be used in a hanging rafter system.

In this version, the saw is done on the rafter leg.

• When using bolts to fasten rafters with slopes, tightening and other wooden elements, it is imperative to install a washer or a metal plate on the bolt, in order to avoid flooding the nut into the wood and, accordingly, weakening the structure.
• Fastening the rafters to the Mauerlat only with nails or self-tapping screws is considered unreliable, so it is imperative to use corners or other metal fasteners of various configurations.

Rich selection of metal fasteners

• When installing rafters on wooden walls, whether it is a hanging or layered system, it is recommended to fasten them to the Mauerlat with a sliding fastener, especially if the roofing material is heavy enough.

Fastening the rafters to the Mauerlat - how to do it correctly?

One of the most important connecting nodes in the roof structure is the fastening of the rafters to the Mauerlat. There are several approaches to solving this problem.

The rafter structure is the skeleton of the roof, which must take over and evenly distribute the weight roofing materials... If you correctly assemble a wooden frame for insulation, waterproofing film and topcoat, then it will turn out to achieve a noticeable increase in the carrying capacity of the rafter system.

The main elements of the rafter system

The timber roof frame is assembled from parts such as:

• Mauerlat - a kind of base for roofing elements, attached along the entire perimeter of the building to the upper edge of the outer walls in order to disperse the pressure of the roofing cake;

  Mauerlat serves as the basis for the roof frame

• rafter legs - irreplaceable parts of the wooden roof skeleton, which determine the angle of inclination of the slopes and the appearance of the upper part of the house;
• ridge girder - a bar fixed in a horizontal position and, like a spine, connecting all the roof frame rafters in their upper part;

  The ridge run is located exactly in the middle of the building

• side girder - a horizontal bar, which differs from the ridge girder in that it is fixed in the middle of the rafter legs of each roof slope;
• tightening - a spacer connecting two opposite rafters so that they do not part;

  Tightening and braces are necessary to properly distribute the load on the Mauerlat

• racks - vertical frame elements placed under the ridge and side girders in order to support the rafters and ridge beams, and also, if necessary, substituted under the middle part of the rafter legs;
  

  Racks can support not only the ridge of the roof, but also the rafters

• struts - parts resting on the bed, due to which the rafter legs become more stable;
• log - a bar located on the upper edge of the inner wall of the building parallel to the ridge and serving as a platform for attaching racks and struts;

  Lezhen is located on the inner wall parallel to the Mauerlat bar

• roof ridge - the area where two slopes are combined, along which a solid lathing is installed, which is necessary to strengthen the described part of the roof;

  The ridge is formed in the highest area of ​​the rafter system

• filly - elements used in the arrangement of the overhang, when the rafter legs are not long enough;
  

  The filly lengthen the rafter legs

• roof overhang - zone timber frame protecting the walls of the house from contact with a large amount of precipitation;

  An eaves overhang is constructed to protect the walls from rain

• sheathing - beams or boards, nailed perpendicular to the rafters and serving as a platform for attaching roofing materials.

  Sheathing boards are laid out perpendicular to the rafters

Main connectors

The main nodes of the rafter system are:

• roof truss- connection of a pair of rafters, stretching, as well as racks and braces;
• ridge knot - combining two opposite rafters;
• a link from a Mauerlat and a rafter resting on it;
• a module that includes a girder, a rack and a bed;
• connection of rafters with a strut and a rack.

The most complex link in the roof frame, according to the author, is a truss truss, which differs in that:

The ridge knot also has several features:

Rafters and Mauerlat become a single link, which is characterized by the following:

The module is formed from a purlin, a rack and a leg, by driving into the places of their connections. construction brackets, steel pins or strips of steel.

The knot of the bed, the post and the purlin allows the load to be shared between the outer and inner walls of the building

The braces, posts and rafters are assembled into a single module, creating clearings. So that their connection is not weak, construction brackets are used.

A knot of struts, struts and rafters allows you to relieve pressure on inner wall Houses

Methods for attaching rafters

In the lower part, the rafters can be connected to both the Mauerlat and the floor beams. Sometimes, for example, when frame construction, they are fixed directly to the wall. And in the upper part, the rafter legs are combined with the ridge. Each designated node can be created in several ways.

Mauerlat connection

The rigid fastening of the rafters to the Mauerlat guarantees the absence of any displacement of the assembly elements. It is performed by cutting in a certain sequence:

1. To speed up the work, a template is made from a piece of board or thick cardboard. A line is drawn on the workpiece, leaving a distance equal to 1/3 of the rafter width from the side edge, and then marking the point of contact with the Mauerlat bar, along which a second line is drawn, perpendicular to the first.

   If the width of the rafter is more than 200 mm, then the cut is made at a depth of 70 mm

2. Tilt angle roof slope the template is substituted to the edge of the Mauerlat, making sure that the point marked on the piece of wood is strictly opposite the corner of the bar. Two lines are drawn from it with a pencil - vertical and horizontal, as a result of which a triangle is obtained on the workpiece, which is carefully cut out.
3. The prepared template is evaluated for correctness by placing it on the Mauerlat in several places. If the groove made is less or more than necessary, then the pattern is made anew, correcting the mistake.
4. The template is placed on a horizontal rafter. The triangle in the pattern is outlined with a pencil. Do the same with the other rafter legs. At the same time, make sure that the horizontal line of the groove in the pattern is in the same place of the rafter every time. Otherwise, the notches will be created at different distances from the ridge.
5. The triangles drawn on the rafters are cut out with a hand hacksaw. They act slowly with the tool, so as not to accidentally increase the depth of the groove in the rafter leg. With the skills of working with an electric saw, you can make grooves with this device. True, it must be borne in mind that a tool operating from the mains is much less obedient to the hand and is able to go to the side.

   The triangular cut allows the rafter to rest against the Mauerlat

6. The correctness of the size of the grooves made is checked with a template. If inconsistencies are found, the notch is corrected with a hacksaw.
7. Two extreme rafter legs are placed on top of the house. They are inserted with grooves into the Mauerlat, fixing from the sides with metal corners or brackets.
8. A rope is pulled along the bottom edge between the two installed elements. Then the remaining rafter legs are attached to the Mauerlat one by one.

The technology of attaching the rafter legs to the Mauerlat with a stripe of a persistent bar can be taken into account by builders without experience. With this method of creating a knot, as the author of the article noted, it is possible to change the position of the rafters until it becomes completely correct.

To connect the main elements of the roof frame with the Mauerlat with a stripe of a persistent bar, do the following:

When building a roof frame for a wooden frame, which always shrinks, they prefer to use the sliding method of attaching the rafters to the Mauerlat. Thanks to him, it is possible to avoid deformation of the rafter structure and deterioration of the stability of the upper row of logs, which replaces the Mauerlat.

Choice sliding rafters is justified only when a ridge bar is provided for the main elements of the roof frame, against which they could abut with their upper part.

When the rafters are fixed to the Mauerlat with a sliding method, certain steps are taken:

The forced method of attaching the rafters to the Mauerlat is adopted when the purchased lumber was shorter than necessary. Also, this method of fixing the main elements of the rafter system is used during the repair of a roof of a complex configuration.

When fastening the rafters to the Mauerlat using the layered method, only 3 tasks are performed:

Video: installing rafters

Alignment with floor beams

It is possible to fasten the rafters to the floor beams only being sure that the walls of the building will withstand the pressure of the roof frame. Still, in the absence of a Mauerlat, the load on the house is not uniform, but pointwise.

Without fear and doubt, the rafters are attached to the floor beams if they are building a light mansard roof. Moreover, as ceiling beams use boards with a section of 5x15 cm.

The rafters are not connected to the Mauerlat, but to the attic beams, if they know for sure that they will withstand the pressure exerted

To firmly fix the rafter legs on the floor beams, perform the following tasks:

Wall mount

If, for some reason, the rafters have to be fixed directly on the walls, then they will definitely need to be tightened. She, as the author of the article, who helped build the roof of the utility room, was personally convinced, will remove from the house some of the stress transmitted by the rafter legs.

The rafters should never be directly connected to outside walls buildings, if they are built of foam or aerated blocks. These materials freely transfer their moisture to the wood and are unable to retain the fasteners.

On the wall, the rafters can be fixed with a sliding method, but this is not the most reasonable solution.

In order to securely fix the rafter legs on the walls, it is necessary to take certain measures:

1. At the right angle, make a wash down on the rafters with one tooth.
2. Install the rafters on the walls with their butt ends and drive a nail 10–12 cm long into them.
3. If necessary, attach metal corners to the sides of the rafters.

Since the ridge of the roof is under severe pressure from the entire rafter system, experienced roofers create a ridge knot in five ways: end-to-end, on a beam, overlapping, in a groove, in a half-tree.

To create a ridge knot by joining opposite rafters butt-to-end, do the following:

When attaching the rafters to a beam, or rather, to a special ridge girder, they act in a special way:

When the rafters are connected to the beam, the ridge is not spiky, but flat.

If the ridge knot is made by fastening the rafters with an overlap, then you will need to perform several simple tasks:

To connect the rafter legs into a ridge knot using a groove, several skillful carpentry actions are performed:

Having chosen the method of connecting rafters in half a tree, do the following:

Video: construction of a roof frame with a ridge girder connection

You should not start the construction of the rafter system until you can figure out the features of attaching the rafters to other elements of the roof supporting structure. By the way, among different ways fixing the rafter legs, there are options not only for experienced builders.