How to fix rafters on a gable roof. How to make a truss system

A roof with two slopes is the most common option for completing the box of a private house. In its manufacture, it is important to correctly select the cross-sections of the supporting elements, securely fasten the nodes and choose the right type of construction. The truss system of a gable roof does not have great difficulties and may well be made by hand.

Classification of truss systems according to the method of support

The structure can be classified in two ways. The first of them is the method of supporting the bearing elements. The gable roof truss system of the house in this case includes the following types:

with layered rafters;
with hanging rafters.

Types of a gable roof with layered and hanging rafters

Roofing with the use of layered rafters involves their support at two points. The design in this case avoids the occurrence of a serious spacer. To do the installation yourself, you will need the following basic elements:

rafter legs;
Mauerlat;
crossbar;
intermediate racks and struts with a large span of load-bearing beams;
crate and counter-crate;
overlays persistent bars.

At the top point, the installation provides for leaning on the crossbar. The installation also provides support at the lowest point - Mauerlat. You can assemble such a structure for a house with your own hands only in two cases:

Options for assembling a layered gable roof system

A layered system is possible if the distance between the gables is not large. That is, such an installation is suitable for a small house with your own hands. The greatest length of the structure, which allows the construction of a wooden crossbar without additional reinforcements, is 6 m. For large spans, it will be necessary to install metal beams as a crossbar. When using a wooden beam, it will be necessary to provide intermediate racks, which are located on average every 2 meters. This can be avoided only when using glued laminated timber of a sufficiently large cross section as a crossbar. In this case, a free layout of the space becomes impossible - the racks in the middle of the room cannot be removed.
The second option, when it is possible to install a layered gable roof system with your own hands, is the presence of a wall in the middle of the house. The device in this case provides that the beam, on which the rafters will rest at the top point, will transfer the load to the inner wall. In this case, the supporting structure should not be confused with the partition. The partition rests on the floors, and installing the wall of the house with your own hands involves resting it directly on the foundations. Such a device is suitable for buildings with sufficient width, where it makes sense to install a wall fence in the middle.

The second option is hanging rafters. They are more complex in calculation, but they allow the installation in the under-roof space of a free-plan house. The design assumes the absence of a supporting wooden or metal bar in the upper part. Installation involves supporting the rafters only at the lowest point. In the upper part, the bearing beams are securely connected to each other. Installing such a system is like a farm. The design works on thrust, so it is important to prevent excessive horizontal load on the walls of the house. You can do this by doing the following:

the device of a monolithic belt along the edge of the walls;
it is necessary to make a reliable fastening of the Mauerlat of a gable roof to the wall of the house with your own hands;
to eliminate the spacer, a contraction is established.

Installation of a hanging truss system

The fight or screed becomes one of the significant elements of the gable roof of the house. It prevents the expansion of the walls under the action of thrust. The following types of fights can be distinguished:

located at the attic floor level;
located at the level of the attic ceiling.

It is worth noting that the second option provides less reliability, since the higher the element is mounted, the stronger the rafters have an effect on it. If the fight turns out to be too long, you need to make it stronger with your own hands. For this, additional elements of the gable roof of the house are installed - suspensions. They connect the skate to the middle of the puff, which prevents it from sagging.

The gable roof truss system with hanging rafters allows you to perform installation with pre-assembly of trusses on the ground, then raise them to the roof and fix them.

This option is only suitable if you have lifting equipment, since the finished gable roofs of the house will become too large and heavy to lift with your own hands.

Classification by type of slope

The second division can be made depending on how the ramp line is designed. The views here suggest the presence of two options:

Gable roof with broken and straight slopes

With straight slopes. The easiest way to do. Allows you to get the job done without any hassle. The disadvantage of this do-it-yourself roofing option is the reduction in attic space.
With broken slopes. Such types of roofing are more difficult to perform. It is assumed that there is a line along which the angle of inclination changes. The angle of inclination of the lower part of the slope must be made greater than that of the upper. Thus, it turns out to raise the ceiling of the attic and increase the free space. The installation of the roof is carried out with the installation of an additional crossbar at the fracture site.

These types involve a choice between them, depending on the wishes of the future owner of the building.

The main elements of the roof

The rafter system of the gable final part of the building consists of many elements. Installation should begin with a detailed study of each of them and the choice of their sections.

When installing elements under a metal tile or other coating, it implies the use of a bar with a section of 150x150 or 200x200 mm. It is this size that allows you to most optimally distribute the load. then you need to choose a method of fixing it depends on the material of the walls. There are several options:

The scheme of fastening the Mauerlat to the wall

Frame, timber or log walls do not require the installation of a Mauerlat. In the case of a frame building, the top framing of the walls serves as a support for the rafter legs. during the construction of fences from timber or logs, the upper crown becomes the Mauerlat. It is important to correctly fix these elements in the wall structure.
When used for the construction of lightweight concrete, additional reinforcement will be required. Lightweight concretes include materials such as foam concrete, cinder concrete, expanded clay concrete. They can collapse if the roof is not supported centrally on them. To evenly distribute the load, a monolithic reinforced concrete belt is poured along the edge of the walls. During work, a special wire, studs or bolts are laid in it, on which the Mauerlat will be fastened.
For brick means, it is possible not to provide a reinforced concrete belt. In this case, to connect with the strapping beam, a wire is inserted into the masonry, which is then wrapped around the Mauerlat and twisted. The second option - one row before the walls are cut, wooden blocks impregnated with an antiseptic are brought into the masonry from the outside. Such plugs and Mauerlat are fastened with staples. It is also possible to use studs and bolts, for fixing which will require pouring a monolithic belt.

An important point is waterproofing.

When installing, it is important to provide roofing material, linokrom or waterproofing at the junction of concrete or brick with wood. This is required to prevent the wood from rotting on contact with material of a different moisture content.

After fixing the Mauerlat, rafter legs are installed. Their cross section is selected depending on the pitch of the supporting beams, their span, snow load and type of coating. When installing a frame under a metal tile with a step of 60 cm, it is recommended to follow the following recommendations, depending on the span:

3 m - 4x15 cm;
4 m - 5=15 cm;
5 m - 5x17.5 cm;
6 m - 5x20 cm.

Table of average values of rafter legs

These are average values, in order to perform a more accurate calculation, it is better to contact a specialist or study additional literature.

There are two ways to fasten the rafter legs to the Mauerlat:

with a notch;
without her.

Fastening rafter legs to the Mauerlat with and without a notch

In the first case, they washed down on the strapping beam, in the second, a special plank is nailed to the rafters, which becomes a persistent bar. Further, for both methods, the work is performed in the same way. With the help of metal corners, the inclined beam is fixed so that it does not move relative to the design position along the Mauerlat. Additionally, nails are driven in at an angle.

Scheme of fastening rafters with wire and brackets

In addition, you will need to fasten the rafter to the wall. The implementation of this measure is provided for in the regulatory documents. You can do this in two ways:

on brackets (suitable for wooden buildings);
using wire twisting (a more time-consuming option, but the only one possible for stone houses).

You can perform fastening according to the norms through one leg. This is necessary for a more secure attachment of the roof to the box of the house.

If you do the work correctly, you can not worry about its condition even in the strongest winds.

Racks, ties, struts

Such elements are most often made of boards. The optimal thickness is in the range of 32-50 mm. Racks are an exception. Here you can use boards with a thickness of 50-100 mm. Fastening is carried out on studs or using support bars.

Gable roof truss system: design and nodes

A gable roof is the most common in construction. For proper installation, it is recommended to study the device of the gable roof truss system.

The device of the truss system of a gable roof

The gable roof truss system is designed for roofing in the form of two rectangles located at a certain angle to each other in the upper part of the structure. This design is often used in the construction of private low-rise buildings, various buildings for domestic and household purposes. At industrial and commercial enterprises, a gable roof is installed on buildings for various purposes, which have a significant length several times greater than the width. The design contains two slopes of different lengths. On the front side, a short slope with a large angle of inclination is installed, on the back - a long one, with a smaller angle of inclination. This configuration allows the main part of atmospheric precipitation to be directed to the non-working zone of the enterprise territory.

Figure 1. Scheme of fillies.

The construction of a gable roof is one of the low-cost options that does not require significant physical effort.

It is performed relatively simply with little experience working with wood material.

Typical bearing elements of the system, specific terms

Figure 2. Scheme of the crate.

In the manufacture of details of the gable roof truss system, softwood lumber is used. Hardwood is undesirable due to its high specific gravity. Most of the elements have specific names that are understood mainly by specialists:

Lezhen - timber with a section of 150x150 mm, 180x180 mm. It is laid on the surface of the internal load-bearing wall. Designed for leveling the surface and distributing loads from racks.
The rafter leg, or rafter, is a piece of timber or thick board. The main element of the triangular roof structure, bearing the main load from snow, rain, wind and other atmospheric phenomena. The distance between the rafter legs can be from 0.6 to 1.2 m. The step size mainly depends on the plumb line of the roofing material, in some cases, the characteristics of the roofing material should be taken into account.
Mauerlat - a square beam with a side size of 150-180 cm. It is laid on the surface of external load-bearing walls. When installing, it must be fixed with anchor bolts or in another reliable way. Distributes the load from the rafter legs to the load-bearing walls.

All parts of a gable roof are interconnected in various ways. Previously, structures were assembled mainly using staples, nails, threaded studs. Now manufacturers of building materials offer a wide range of different brackets for assembling roofs of any configuration. Most parts are fastened with self-tapping screws of the required diameter and length, reinforced with special spikes in the brackets.

Additional elements of the rafter system

Figure 3. Scheme of an arch with three hinges.

In addition to load-bearing parts, additional reinforcing elements are used in the structures:

Filly (Fig. 1) - used to increase the length of the rafter legs. Are established in the lower part for the device of cornice overhang. The thickness of the filly is somewhat less than the size of the rafters.
Roof overhang, or cornice overhang, is a roof element protruding from the edge of the wall by about 40-50 cm. Designed to protect walls from atmospheric precipitation.
The ridge is an element that connects all the rafter legs of the system in the upper part. Installed in a horizontal position.
Sheathing (Fig. 2) - boards or bars installed for fixing the roof. They are located perpendicular to the rafter legs, additionally performing the function of their fastening. They take the main effort from the roofing material, distribute it to the rafters. For the device, it is desirable to use edged lumber. With limited funds, you can use unedged, clearing it of bark. If the roof is made of soft material, the crate is made solid. This option can be made from boards or plywood treated with protective materials from high humidity. When corrugated board is used, the crate is performed with a certain step, depending on the weight of the material and its design features.
Struts - elements made of timber or thick boards that reinforce the main structure. Distribute the force from the rafter legs to the bearing parts. The assembled structure of struts and puffs was called a farm - an enlarged part with the necessary margin of safety.
Racks - are made from pieces of lumber of rectangular or square section. Are established in vertical position under a descent of slopes. The load from the corner connection of the roof rafters is distributed through the posts to the internal load-bearing wall.
Puff - a bar or board that fastens the rafters in a hanging system. Creates a rigid triangle shape between rafter legs, compensating for sprawl.

For the manufacture of additional parts, you can use lumber with a section similar to that of load-bearing parts. In order to save money, you can calculate and purchase products of a smaller section.

Two typical ways to arrange truss systems

Figure 4. Scheme of connecting the lower ends of the parts.

The gable roof truss system can be arranged in two main ways:

hanging rafter system;
layered system.

The hanging system is used for buildings with a distance between the outer walls of less than 10 m, without an internal load-bearing wall in the middle of the building. In a different configuration of the building, a layered rafter structure is used.

If the building has columns located along one of the central axes, it is possible to use a combined option. Rafter legs located above the columns are mounted with emphasis on the surface of the columns, hanging rafters are installed between them.

Hanging truss system

In structures of this type, the installation of truss beams is carried out on the surface of the outer walls. The disadvantage of this method is the occurrence of force, bursting the walls. To compensate for the load, the beams are pulled together by tightening. The design takes the form of a rigid triangle that retains its shape under the influence of loads. In some cases, floor beams can play the role of puffs. Such a scheme is used when arranging an attic in the attic space.

Hanging rafters can be made in various versions:

Scheme of the reinforced structure.

A simple version of the arch with three hinges (Fig. 3) - the design is a rigid triangle, the two sides of which are the rafter legs. The main load creates a bending force on the parts. The force on the third side is aimed at stretching the structure, so instead of a wooden part, a steel tie can be used. The connection of the lower ends of the parts can be assembled in various ways (Fig. 4), by inserting beams into a puff, using wooden elements or metal brackets.
Reinforced structure (Fig. 5) - a gable truss system used for roofing of large industrial buildings with a distance between walls of more than 6 m. This system is not suitable for use in small residential buildings. A design feature is the distribution of the puff weight on the skate. Since it is almost impossible to find solid lumber of the required length (6 m or more), the puff is made from segments. The connection of all elements is carried out by a straight or oblique inset. The central part is called the headstock. The connection of the headstock with a tightening is performed by a collet twist with the possibility of adjusting the tension.
The device of an arch with a tightening in the upper part of the rafters (Fig. 6) is used for equipment in the attic space of the attic. At the same time, the tensile force in the rafter beams increases. The lower ends of the beams are attached to the Mauerlat bars. The fastening should limit the movement of the beams to the sides along the beam, but allow sliding across. This ensures uniform load distribution and stability of the entire system. Rafter beams should form an overhang.

Many variants of hanging-type systems have been developed. Most are used for relatively small buildings without load-bearing structures inside buildings. For larger buildings, a layered rafter system should be used.

Layered truss system

The main difference of this system is the installation of a vertical beam resting on an internal load-bearing wall located in the middle of the building. This design is necessary when a gable roof is installed on a building with a wall spacing of more than 10 m.

Figure 6. Arrangement of an arch with a puff at the top of the rafters.

A properly executed system of non-expanding rafter beams allows you to get rid of the forces that burst the walls. The surface of the slopes is subjected only to the bending force. There are 3 main options for the device of such systems. With all options, the lower ends of the rafters are attached according to the sliding support method. For insurance, an additional mount is installed between the support bar and the rafter leg.
You can use a steel strip, wire tie. The options differ in the method of connecting the upper ends of the rafters, docking with the ridge beam. One of the options involves laying rafters on a beam in the form of a sliding support with a cutout device. Mounting can be done using brackets or special brackets. The gable roof, arranged according to the following option, is the most popular because of the simplicity of the device. The top of the rafters can be made end-to-end or overlay with cutting grooves. The corner must be fastened in any of the available ways and fixed on the ridge beam. The third option involves a rigid connection of the run and rafters. For mounting on rafter legs, pieces of boards are stuffed on two sides. A large bending force is formed on the beam, but the load on the rafter beams is reduced.
A gable roof for a building with dimensions up to 14 m must have a reinforced truss system. One of the options for increasing strength is the installation of a strut. The part takes on the load from the rafter leg, experiencing a compressive force. To correctly select the installation position of the element, you need to measure the angle of 45-53 ° from the horizontal plane of the building. An additional support device turns an ordinary beam into a reinforced version, consisting of two spans. To install the struts, calculations are not required, you just need to fix it under the rafter, cutting out the joint angle with maximum accuracy.

The technology for installing gable roofs is simple, you can do everything yourself. Work must begin with the installation and fastening of the base to the walls, then mount the gables. It is desirable to carry out work on the manufacture of truss beams and enlargement of structures on the ground, to lift the assembled elements, install them on the building, and fix them with temporary fasteners. After assembling and installing all the elements, you should fix the crate and proceed with the installation of the roof.

Gable roof truss system: installation and diagrams

The gable roof truss system is designed for roofing in the form of two rectangles located at a certain angle to each other in the upper part of the structure.

Do-it-yourself gable roof truss system: an overview of hanging and layered structures

Rafters perform a number of significant roofing functions. They set the configuration of the future roof, perceive atmospheric loads, and hold the material. Among the rafter duties are the formation of even planes for laying the coating and providing space for the components of the roofing pie. In order for such a valuable part of the roof to flawlessly cope with the listed tasks, information about the rules and principles of its construction is needed. The information is useful both for those who are building a gable roof truss system with their own hands, and for those who decide to resort to the services of a hired team of builders.

Rafter structures for gable roofs

In the device of the truss frame for pitched roofs, wooden and metal beams are used. The starting material for the first option is a board, log, timber. The second is constructed from rolled metal: a channel, a profile pipe, an I-beam, a corner. There are combined structures with steel most loaded parts and wood elements in less critical areas.

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

In the case of self-construction of truss structures for private houses, wood is a priority. It is easy to work with it, it is lighter, “warmer”, more attractive in terms of environmental criteria. In addition, nodal connections do not require a welding machine and welder skills.

Rafters - a fundamental element

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

The rafters used in the construction of the gable roof frame are divided into:

Layered rafter legs, both heels of which have reliable structural supports under them. The lower edge of the layered rafter rests on the Mauerlat or on the ceiling crown of the log house. The support for the upper edge can be a mirror analogue of an adjacent rafter or a run, which is a beam horizontally laid under the ridge. In the first case, the truss system is called spacer, in the second, non-spacer.
hanging rafters, the top of which rests against each other, and the bottom is based on an additional beam - puff. The latter connects the two lower heels of adjacent rafter legs, resulting in a triangular module called a truss truss. The tightening dampens the tensile processes, so that only a vertically directed load acts on the walls. The design with hanging rafters, although it is spacer, does not transfer the spacer itself to the walls.

In accordance with the technological specifics of the rafter legs, the structures constructed from them are divided into layered and hanging. For structural stability, they are equipped with struts and additional racks. For the arrangement of supports for the top of the layered rafters, beds and girders are mounted. In reality, the truss structure is much more complicated than the elementary patterns described.

Note that the formation of a gable roof frame can generally be carried out without a truss structure. In such situations, the alleged planes of the slopes are formed by slegs - beams laid directly on the bearing gables. However, we are now specifically interested in the device of the gable roof truss system, and it can involve either hanging or layered rafters, or a combination of both types.

Subtleties of fastening rafter legs

The rafter system is fastened to brick, foam concrete, aerated concrete walls through the mauerlat, which in turn is fixed with anchors. Between the Mauerlat, which is a wooden frame, and the walls of these materials, a waterproofing layer of roofing material, waterproofing, etc. is necessarily laid.

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

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

How to do without furious calculations?

It is highly desirable that the cross section and linear dimensions of the wooden beams be determined by the project. The designer will give clear calculation justifications for the geometric parameters of the board or beam, taking into account the entire range of loads and weather conditions. If there is no home design development master at his disposal, his path lies on the construction site of a house with a similar roof structure.

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

The installation step of the rafters determines the type and weight of the roofing. The heavier it is, the smaller the distance between the rafter legs should be. For laying clay tiles, for example, the optimal distance between the rafters will be 0.6-0.7 m, and for the installation of metal tiles and profiled sheets, 1.5-2.0 m is acceptable. However, even if the step required for the correct installation of the roof is exceeded, there is a way out . This is a reinforcing counter-lattice device. True, it will increase both the weight of the roof and the construction budget. Therefore, it is better to deal with the step of the rafters before the construction of the rafter system.

Craftsmen calculate the pitch of the rafters according to the design features of the building, tritely dividing the length of the ramp into equal distances. For insulated roofs, the step between the rafters is selected based on the width of the thermal insulation boards.

Rafter structures of layered type

Rafter structures of the layered type are much simpler in execution than their hanging counterparts. A justified plus of the layered scheme is to provide full ventilation, which is directly related to the longevity of the service.

Distinctive design features:

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

The minus of the scheme is the presence of structural elements that affect the layout of the internal space of the operated attic. If the attic is cold and the organization of useful premises is not supposed to be in it, then the layered construction of the truss system for the installation of a gable roof should be preferred.

A typical sequence of work on the construction of a layered truss structure:

First of all, we measure the height of the building, the diagonals and the horizontalness of the upper cut of the skeleton. When identifying vertical deviations of brick and concrete walls, we eliminate them with a cement-sand screed. Exceeding the heights of the log house we squeeze. By placing chips under the Mauerlat, vertical flaws can be dealt with if their magnitude is insignificant.
The floor surface for laying the bed must also be leveled. He, the Mauerlat and the run must be clearly horizontal, but the location of the listed elements in the same plane is not necessary.
We process all wooden parts of the structure before installation with fire retardants and antiseptic preparations.
We lay waterproofing on concrete and brick walls for the installation of a Mauerlat.
We lay the Mauerlat beam on the walls, measure its diagonals. If necessary, we slightly move the bars and turn the corners, trying to achieve the perfect geometry. Align the frame horizontally if necessary.
We mount the Mauerlat frame. The splicing of the beams into a single frame is carried out by means of oblique cuts, the joints are duplicated with bolts.
We fix the position of the Mauerlat. Fasteners are made either with brackets to wooden plugs laid in the wall ahead of time, or with anchor bolts.
We mark the position of the bed. Its axis should recede from the Mauerlat bars at equal distances on each side. If the run will be based only on racks without lying down, the marking procedure is carried out only for these columns.
We install the bed on a two-layer waterproofing. We fasten it to the base with anchor bolts, connect it to the inner wall with wire twists or staples.
We mark the installation points of the rafter legs.
We cut out racks according to uniform sizes, because our bed is set to the horizon. The height of the racks must take into account the dimensions of the section of the run and the bed.
Installing racks. If provided by the project, we fix them with spacers.
We lay the run on the racks. We check the geometry again, then install the brackets, metal plates, wooden mounting plates.
We install a trial rafter board, mark the places of trimming on it. If the Mauerlat is set strictly to the horizon, there is no need to adjust the roof rafters in fact. The first board can be used as a template for making the rest.
We mark the installation points of the rafters. Folk craftsmen for marking usually prepare a pair of slats, the length of which is equal to the gap between the rafters.
According to the markup, we install the rafter legs and fasten them first at the bottom to the Mauerlat, then at the top to the run to each other. Every second rafter is screwed to the Mauerlat with a wire bundle. In wooden houses, the rafters are screwed to the second crown from the top row.

If the rafter system is done flawlessly, the layered boards are mounted in random order. If there is no confidence in the ideal structure, then the extreme pairs of rafters are installed first. A control twine or fishing line is stretched between them, according to which the position of the newly installed rafters is adjusted.

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

Hanging truss systems

The hanging type of truss systems is a triangle. The two upper sides of the triangle are folded by a pair of rafters, and the puff connecting the lower heels serves as the base. The use of tightening allows you to neutralize the effect of the thrust, therefore, only the weight of the crate, the roof, plus, depending on the season, the weight of precipitation, acts on walls with hanging truss structures.

The specifics of hanging truss systems

Characteristic features of hanging type truss structures:

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

The advantages of the hanging scheme include the space under the roof free from racks, which allows you to organize an attic without pillars and partitions. There are disadvantages. The first of these is the limitation on the steepness of the slopes: their slope angle can be at least 1/6 of the span of a triangular truss, steeper roofs are strongly recommended. The second disadvantage is the need for thorough calculations for the competent device of cornice nodes.

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

Subtleties of long-span hanging systems

Puff - the longest element of the hanging rafter structure. Over time, it, as is typical of all lumber, deforms and sags under the influence of its own weight. Owners of houses with spans of 3-5m are not too concerned about this circumstance, but owners of buildings with spans of 6 meters or more should think about installing additional parts that exclude geometric changes in tightening.

To prevent sagging in the installation scheme of the truss system for a large-span gable roof, there is a very significant component. This is a pendant called a grandmother. Most often, it is a bar attached with wooden surfs to the top of the truss truss. You should not confuse the headstock with the racks, because. its lower part should not come into contact with the puff at all. And the installation of racks as supports in hanging systems is not used.

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

Adjustment of the tightening position can be arranged in the zone of the ridge knot, and the headstock can be rigidly connected to it with a notch. Instead of a bar in non-residential attics, reinforcement can be used to manufacture the described tightening element. It is also recommended to arrange a headstock or suspension where the puff is assembled from two bars to support the connection area.

In an improved hanging system of this type, the headstock is complemented by strut beams. The stress forces in the resulting rhombus are extinguished spontaneously due to the competent arrangement of the vector loads acting on the system. As a result, the truss system pleases with stability with a slight and not too expensive upgrade.

Hanging type for attics

In order to increase the usable space, the tightening of the rafter triangles for the attic is moved closer to the ridge. A perfectly reasonable move has additional advantages: it allows you to use puffs as the basis for filing the ceiling. It is attached to the rafters by cutting with a semi-frying pan with a duplication of a bolt. It is protected from sagging by installing a short headstock.

A noticeable drawback of the attic hanging structure is the need for accurate calculations. It is too difficult to calculate it on your own, it is better to use a ready-made project.

Which design is more cost effective?

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

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

Saving on the grade of material will not work. For the bearing elements of both systems: rafters, purlins, beds, Mauerlat, attendants, racks, lumber of the 2nd grade is needed. For crossbars and puffs working in tension, you will need the 1st grade. In the manufacture of less responsible wooden slips, the 3rd grade can be used. Without counting, we can say that in the construction of hanging systems, expensive material is used to a greater extent.

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

There are actually many more methods for constructing truss systems for roofs with two slopes. We have described only the basic varieties that are actually applicable for small country houses and buildings without architectural ideas. However, the information provided is sufficient to cope with the construction of a simple truss structure.

Do-it-yourself gable roof truss system: device, design, installation

In order for the truss system of a gable roof to be built competently and firmly with your own hands, you need information about the rules and principles of the device, fastening and

Construction of houses

When building one-story houses, a 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. In the device, a gable rafter roof is not too complicated. And you will successfully master this work on your own.

The design of the gable roof truss system

The gable roof consists of two inclined surfaces that have a rectangular shape. Thanks to this, precipitation, which is represented by rain and melt water, flows off the roof in a natural way. The gable roof has a rather complex structure. It consists of such structural units: Mauerlat, rafter system, filly, ridge, roof overhang, bed, struts, puffs, crate and racks:

Mauerlat. This element performs the functions of transferring and distributing the load created by the rafter system on the load-bearing walls of the house. For the manufacture of Mauerlat, a beam is used, which has a square section - from 100 by 100 to 150 by 150 mm. It is better to use softwood. The beam is placed around the perimeter of the building and fixed to the outer walls. For fastening use special rods or anchors.
Rafter leg. Rafters form the main frame of 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 section of 100 by 150 or 50 by 150 mm. Choose a rafter pitch of about 60-120 cm, depending on the type of roofing material. When using a heavy coating, place the rafter legs more often.
Skate. This element connects two slopes at the top of the roof. The ridge is formed after connecting all the rafter legs.
Filly. 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 an overhang to form. To make this structural unit, take a board that has a smaller section than the rafter. The use of fillies facilitates the construction of the truss system, as it allows the use of short rafters.
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 destroyed. The overhang protrudes from the wall, as a rule, by 400 mm.
Sill. It is located on the inner wall and serves to evenly distribute the load from the roof racks. For the manufacture of bedding, a beam is used, which has a section of 150 by 150 or 100 by 100 mm.
Racks. These vertical elements are responsible for transferring the load from the ridge to the interior walls. To create this element, prepare a beam that has a square section of 150 by 150 or 100 by 100 mm.
Struts. They are needed to transfer loads from the rafters to the load-bearing walls. Struts and puffs form a solid structure called a truss. Such a device is designed to withstand loads at large spans.
Puff. This structural unit, together with the rafters, forms a triangle. It does not allow the rafters to part in different directions.
Crate. This design consists of boards and bars. They are attached perpendicular to the rafters. Sheathing is necessary to evenly distribute the weight of the roof covering and the loads created by weather phenomena on the rafters. In addition, the crate is required to fasten the rafters together. When arranging a soft roof to create a crate, you should not use boards and bars, but moisture-resistant plywood.

Varieties of gable roof truss system

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

At the same time, the rafters and tightening form a rigid geometric figure - a triangle. It is not able to deform under loads that are in any direction. The puff will be stronger and more powerful if it is placed higher. The floor beams act as puffs. Thanks to their use, the hanging rafter system of a gable roof acts as the basis for the arrangement of the attic floor.

Laminated rafters in their design have a support beam, which is located in the middle. It is responsible for transferring the weight of the entire roof to the intermediate column or middle wall located between the outer walls. It is recommended to install shear rafters if the outer walls are spaced more than 10m apart. If columns are present instead of interior walls, you can alternate between shear and hanging rafters.

Do-it-yourself gable truss system

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

Calculation of a gable roof

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

When building a gable roof, remember that it must slope at an angle of more than 5 degrees. It happens that the slope of the roof reaches 90 °.
For areas with heavy rainfall, and when the roofing does not fit snugly, 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 output will be a broken roof structure. It will have a flat upper part, and on the lower part there will be a sharp slope.
In regions with strong gusts of wind, sloping roofs are equipped. 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. Equip a gable roof that is not too steep. But also the slope should not be very gentle.
When choosing a large angle of the roof, its windage increases, and, accordingly, the price of the gable roof truss system and the crate. After all, such a slope entails an increase in the area of \u200b\u200bthe roof and, accordingly, the amount of necessary material - building and roofing.

When buying materials for the construction of a gable roof, it is useful to calculate its area:

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

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

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.
Calculate the weight of the roof by adding up the weight of each layer of the "pie" - heat-insulating, vapor barrier and waterproofing materials, truss system, battens and directly roofing material. Calculate the weight per 1 m2.
Increase the result by 10%. You can also take into account the correction factor. In our case, K=1.1.
If you plan to change the design of the roof over time and increase the angle of its inclination, then include a margin of safety in the calculation. Take immediately higher load indicators than those that you received at the time of the calculation. It is recommended to build on the value, which is 50 kg per 1 m2.
When calculating the load exerted by atmospheric phenomena, take into account the climatic features of the area where the building is located. In this calculation, take into account the slope of the slope. If the gable roof forms an angle of 25 degrees, then take the snow load equal to 1.
If the roof is equipped with a greater slope - up to 60 degrees, the correction factor reaches 1.25. Snow load for an angle greater than 60 degrees is not taken into account.
The rafters transfer the entire load from the created structure to the load-bearing walls. Therefore, their parameters must also be taken appropriately. Select the section and length of the rafter leg, depending on the current load on the roof and the angle of the slope. Increase the values obtained by 50% to ensure a high margin of safety.

Mauerlat installation methods

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

If logs or timber were used to build the walls, then the upper timber will act as a Mauerlat, as shown in the photo of the gable roof truss system.
If you used bricks to build walls, then brick the metal rods into the masonry. They must have a cut thread for attaching the Mauerlat. Install rods every 1-1.5 m. Choose rods with a diameter of at least 10 mm. Lay waterproofing between masonry and 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 are threaded to the reinforcement.
For Mauerlat, use a beam that has a section of 15 by 15 cm. It will act as a kind of foundation for the truss system.
Lay 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, as otherwise it may be torn off by the wind.
Mauerlat is recommended to be placed on top of the waterproofing layer. To connect all the parts into one whole, use bolts and metal plates.
To avoid sagging, make a lattice of racks, struts and a crossbar. To do this, take boards measuring 25x150 mm. The angle between the strut and the leg of the rafter should be as straight as possible.
If using a rafter leg that is too long, install another support. She must lean on the bed. Each element is associated with two adjacent ones. As a result, a stable structure is created around the entire perimeter of the roof.

Rafter leg attachment

The best option for a gable roof truss system is a combination of sloping and hanging rafters. This design allows you to create a reliable gable roof and reduce the cost of building materials. Consider the following recommendations when working:

Use only the highest quality wood as a material. Beams that have cracks and knots should not be used.
Rafters have standard dimensions - 50x150x6000 mm. When the 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.
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 a board along them. The template is ready.
Cut the rafters according to this pattern. After that, do the top washed down on them.
Take the resulting workpiece, bring it to the floor beam to mark the lower cut in place.
Install all rafters. At the same time, remember that after installing one leg, you must immediately install the opposite one. So you will quickly remove the lateral loads on the ridge beam.
If the slope is too long, then standard boards will not be enough to make a rafter leg. In this case, you can splice two boards together. To do this, sew on them a piece of wood of a similar section. It should have a length of 1.5 - 2 meters. According to the diagram of the gable roof truss system, the joint should always be at the bottom. Under it, install an additional rack.
Attach the rafter leg to the ridge beam with nails. Use self-tapping screws to fasten the rafters to the floor beam. Metal mounting plates are also suitable. In addition, a few nails are added.
If you are building a structure exclusively from hanging rafters, then skip the next step. When erecting a structure with layered rafters, you need to think about the supports that are installed on their floor. To reduce the deflection of the rafters, correctly calculate the location of such supports.
If you're building a gabled mansard roof, the intermediate studs will form the frame for the side walls.
When performing this work, maintain a certain step of the beams. Set its size at the design stage.
After installing the rafters, attach the ridge. It is located on their upper edge. For fastening use metal corners or staples. Bolts are the most popular.

Giving structure rigidity

After installing the gable roof truss system, strengthen it using the technology 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 with a puff and from above with a bolt.
For large buildings that are light at the same time, provide a lightweight roof. The walls must support it.
If the house has a width of 6-8 m, then the structure should be tightened. Install in the middle of the support. Such racks are called grandmas. 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 an 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 bottom end of the headstock and to each other as shown in the gable roof truss video.
In a situation with long roofs, gable beams should be relieved. This is done by installing braces. The upper end should rest against the corner of the gable. The lower one is mounted on the central floor beam. For fasteners, use a beam that has a large cross section. So you can prevent them from breaking if there are strong gusts of wind.
In areas where winds predominate, the rafters must be resistant to such influences. Strengthen them by installing diagonal ties. Boards are nailed from the bottom of one rafter to the middle of the next.
For greater rigidity, when creating the most critical fasteners, it is better not to use nails. Use pads and metal fasteners for this. Nails will not be able to provide high-quality fastening, since the wood can dry out after some time.

Lathing of the truss system

The final stage of the construction of the gable roof truss system is the creation of the crate. It is on it that you will lay the roofing. Carry out the work in the following sequence:

Select a dry timber for the crate. It should not have cracks or knots. Nail the bars on the bottom. Attach two boards near the ridge so that there are no gaps. The lathing must withstand the weight of the top roofing material and not sag under the weight of the workers.
If you will equip a soft roof, make two layers of sheathing. One is sparse, the other is solid. The same applies to roll roofing. To begin with, parallel to the ridge beam, place boards 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 that, check that there are no errors left on the crate - bumps and knots. Also check that the nail heads are not sticking out.
Lay one layer of timber under the metal tile. It should have a section of 50 by 60 mm. Do the same when using slate or steel roofing sheets. Maintain a step between the timber, depending on the roofing you choose - from 10 to 50 cm. Hammer nails closer to the edges of the board, and not in the middle. Drive hats deep. So they will not be able to damage the roof later. If you are making a crate for a metal tile, then remember that the connection of the timber at the same level should fall on the rafters.

When you have installed and strengthened the gable roof truss system, you can start installing the roofing pie. Place a thermal insulation material between the rafters, 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, fasten the roofing material.

The device of the gable roof truss system, Building Portal

Construction of houses In the construction of one-story houses, a roof with two slopes is very popular. This is due to the speed of construction of the structure. For this setting,

The arrangement of a gable roof is considered a very practical and right decision in the construction of a residential or commercial building. This option combines the relative simplicity of execution and reliability, ease of maintenance and long service life. In this material, we will talk about how to install a gable roof truss system with your own hands, what are its varieties, and how to calculate the dimensions of its individual elements. Our step-by-step instructions will allow you to deal with any complications that may arise in the process.

A roof with two slopes has a whole list of advantages:

ease of calculation;
various versions;
saving materials;
the possibility of natural outflow of water;
low probability of water leakage due to the integrity of the structure;
the possibility of arranging an attic or attic;
reliability and long service life;
ease of preventive maintenance.

Varieties of gable roofs

Consider the main types of roofs with two slopes, the truss system in which will differ slightly in execution.

Symmetrical gable roof

This is the simplest gable roof, however, the most reliable and in demand. Symmetrical slopes allow you to distribute the load on the Mauerlat and load-bearing walls evenly. In this case, the type and thickness of the insulation layer do not affect the choice of roofing material. Thick beams of rafters have a sufficient margin of safety, so they will not sag. In addition, spacers can be installed at your discretion.

Among the disadvantages of this option, one can only note a too sharp angle of the slopes, which makes it difficult to use the attic floor and creates "deaf" zones that have no use.

Roof with two asymmetrical slopes

If the angle of inclination of the slopes is made more than 45º, some unused areas of space can be used. It will even be possible to equip a living space in the attic. However, some additional calculations will be required, as the load on the walls will become uneven.

Broken roof with external or internal break

This configuration makes it possible to place a spacious attic or attic under the roof. However, in this case, more complex engineering calculations will be required.

The design of rafters for arranging a roof with two slopes

The design of the gable roof truss system assumes the presence of such components:

Mauerlat. It is a durable bar made of oak, pine, larch or other strong wood, which is laid around the perimeter on the bearing walls of the building. The purpose of the Mauerlat is to evenly distribute the load. The cross section of the bars is chosen based on their structure - solid or glued, as well as on the age of the building. The most commonly used beams are 100 × 100 or 150 × 150 mm.
rafters. The whole structure is created from such elements (read also: ""). Connecting at the top point, two rafters form a farm. They are made from logs or durable bars.
puff. This part serves to grip the rafters and ensure their rigidity.
Runs. In those places where the rafter legs are joined, a ridge run is attached, on which the skate will subsequently be mounted. And with the help of side runs, the frame of the rafters is given additional strength. The expected load determines the size and number of such elements.
Rafter rack. This is a vertical beam that partially takes over the weight of the roof. If the gable roof scheme is simple, then one such beam is placed in the center. For a long span, three bars may be required - one in the center and two on the sides. If an asymmetrical roof is being erected, then the location of such a beam is determined by the length of the rafter legs. Under the rafters for a sloping roof, racks are placed on the sides to make room for movement. Beams are placed in the center and sides if there are two rooms.
Struts. These are rack supports. If significant winds and precipitation are expected in the winter, longitudinal as well as diagonal racks are installed.
Sill. A rack for rafters rests on it, and struts are also attached.

crate. The selected roofing material is attached to it, and you can also move along it during work. Fix the crate perpendicular to the rafters. Please note that the crate allows you to evenly distribute the mass of roofing material over the rafter system.

The installation scheme of the gable roof truss system will greatly facilitate all construction work. How such a roof scheme will look depends on the type of roof.

Please note that the material for the truss system must be of the highest quality, treated with flame retardant and antiseptic agents. There should be no knots or cracks on the beams for rafters, Mauerlat and racks. Only a small number of knots are allowed on the crate, firmly seated in the wood.

Calculation of frame elements for a gable roof

Laying Mauerlat on the walls

This element is mounted on a load-bearing wall along its entire length. If we are talking about a log house, then the upper crown can serve as a Mauerlat. For buildings made of aerated concrete or brick, a Mauerlat equal to the length of the wall will be required. Sometimes this detail can be laid between the rafters.

With a lack of material length for the Mauerlat, several pieces can be spliced. At the same time, the edges are sawn at 90º and joined with bolts - wire, dowels or nails are not suitable.

There are two ways to lay a Mauerlat on top of a load-bearing wall:

symmetrically in the center;
offset in the desired direction.

Mounting of the Mauerlat is carried out on a pre-laid waterproofing layer of roofing material. This will protect the wood from rotting.

It is worth taking a responsible attitude to the process of attaching the Mauerlat, since in strong winds it must withstand a particularly heavy load.

As fasteners for Mauerlat, you can use the following consumables:

Anchors, which are indispensable for monolithic materials.
Wooden dowels. These parts are used in houses made of timber and logs, although they require additional fastenings.
Staples.
Reinforcement or special studs. This option is preferable for buildings made of foam or aerated concrete.
Knitting or steel wire is an auxiliary fastener that is used almost always.

Assembly of trusses or trusses

Farm assembly can be done using one of the following methods:

Beams for rafters are assembled and mounted directly on the roof of the building. This process is quite laborious, since all measurements, trimming and coupling of the bars will have to be done at a height. However, you can do it on your own, without the involvement of technology.
Trusses or truss pairs can be fixed to the ground, and then the finished elements can be raised to the roof of the building. On the one hand, this simplifies the process of installing the rafters, and on the other hand, due to the large weight of the structure, lifting it up will require special equipment.

Please note that it is worth starting the assembly of truss pairs only after marking. And if you make a template in advance, for which you take two boards equal to the length of the rafters, and connect them together, then all pairs will turn out to be exactly the same.

Installation of rafters

After assembly and lifting to a height, the rafters of the gable roof of a wooden house are installed. To fix them on the Mauerlat, cuts are made at the bottom of the rafters. The first to install two trusses from opposite ends of the roof.

After that, a rope is pulled between the starting pairs, along which all the other truss trusses will be aligned and the ridge will be installed.

Now you can mount the remaining pairs in compliance with the calculated step between them. In cases where pairs are assembled directly on the roof, a ridge run is attached between the two end trusses. Subsequently, rafters are installed on it.

The order of installation of halves of rafters according to the opinions of professionals may differ. Some prefer to lay the bars in a checkerboard pattern so as not to overload the foundation and walls during work. Others tend to install pairs of rafters in series. Be that as it may, rafter legs may need props and racks - it all depends on the size of the roof and the shape of the trusses.

Skate mount

A ridge is an element that is formed by attaching rafters at the top point. As soon as all the details of the truss system for a gable roof are installed, it is necessary to perform a major fixing of all structural elements.

Lathing installation

The presence of lathing is mandatory in the construction of any roof. It not only supports the roofing material and allows it to be securely fastened, but also makes it possible to move along the roof during work.

The distance between the individual boards is chosen based on the type of roofing material:

soft roofing is laid on a continuous crate without gaps;
for a metal tile, a crate is needed with a step of 35 cm (between the two lower rows - 30 cm);
slate and corrugated board can be laid on the crate in increments of 44 cm.

Results

Thus, in order to assemble a truss system for a roof with two slopes, many nuances should be taken into account and any possible complications should be foreseen. We hope that our advice will help you cope with this difficult task and create a high-quality and durable roof for your home.

A gable roof is the best DIY option for an inexperienced builder. It is simple in execution, but at the same time reliable and can withstand significant loads from both wind and precipitation. She, of course, is not very beautiful, but in the baths she looks quite organic.

To do everything consciously, it is necessary to understand the structure of a gable roof and the purpose of all its elements. Let's start in order.

Mauerlat

This is a large bar attached to the load-bearing walls around the perimeter of the building. It is this element that accounts for most of the load from the roof. And it is the Mauerlat that transfers it to the load-bearing walls.

For this element, square bars with a size of 100 * 100 mm or 150 * 150 mm are used. They are connected to the walls with embedded studs. If the bath is wooden, then the upper crown usually serves as the Mauerlat. For all other types of walls, a reinforced concrete belt is made into which studs are embedded. Then the beam of the selected section is “put on” on the studs and attracted with nuts. Sometimes it is additionally fixed with long pins.

Since the thickness of the walls is often greater than the width of the mauerlat, it can be laid with bricks from the outside of the timber. This will make the system more reliable. Only wood needs to be wrapped with two layers of roofing material - to protect it from moisture and decay.

Rafter legs and skate

A ridge is a horizontal wooden block located at the top of the roof and connecting two slopes. Rafter legs or rafters rest on it and on the Mauerlat. Since the ridge has a rather large load, it must be made of a considerable section and wood of durable species should be chosen.

The height of the roof ridge is determined based on the slope of the roof and the width of the building. The angle of the roof slope is a value that depends on climatic factors: if there is a lot of snow in winter, then you need to make the slopes steeper. They will snow well. If there are strong winds in the region, the high roof will experience heavy loads and may be damaged.

For medium conditions, the optimal roof slope angle is about 35°-45°. They will not be heavily loaded by the wind, and the snow will not accumulate much. In addition, with such an angle, you can choose any type of roofing: any of the tiles, soft roofing, slate, metal tiles.

Also remember, the higher the ridge is raised (the steeper the slopes), the larger the roof area will be. And this will lead to the fact that the cost of purchasing roofing materials and the amount of work will be large.

Knowing the slope angle and the width of your bath, you can calculate the height of the roof ridge. To do this, the width of the building must be divided by two (if the ridge is in the middle, and not shifted to one side or the other) and multiplied by the slope angle tangent (the first formula in the figure). In order not to look for the necessary coefficient in mathematical tables, it is written out and summarized in a simple table.

Roof slope angle	5	10	15	20	25	30	35	40	45	50	55	60
Tg A (skate height calculation)	0,08	0,17	0,26	0,36	0,47	0,59	0,76	0,86	1	1,22	1,45	1,78
Sin A (rafter length calculation)	0,09	0,17	0,26	0,34	0,42	0,5	0,57	0,64	0,71	0,77	0,82	0,87

Multiply half the width of the house by this factor. Get the height of the ridge for your bath. For example, the width of the bath is 4 meters, the angle is 35 °. We consider: 4 m / 2 * 0.76 \u003d 1.52 m - the height of the ridge from the ceiling.

Now about the rafter legs. They are made from pine or spruce bars, or better - larch. Section 50*150 mm or 50*100 mm. The choice of bar thickness depends on:

The length of the rafter leg is also calculated according to the mathematical formula: the height of the ridge is divided by the sine of the angle of inclination (the second formula in the figure). The sines of the tilt angles are also in the table. Find the right value and count. For example, for the ridge we found is 1.52 m and the angle of inclination is 35 °, the rafters will need 1.52 m / 0.57 = 2.67 m.

Roof overhang and filly

But the roof does not end exactly above the load-bearing wall. It extends beyond the walls by about 40 cm. This ledge is called the roof overhang. This is done so that the water flows further from the foundation, does not wash it away. Therefore, the rafter legs are taken longer. If their length is not enough, they are grown with boards, which are called "fillies".

To organize the overhang of the roof, boards are added to the rafters - filly

Types of truss systems

Rafter systems come with hanging or layered rafter legs. The hanging ones rest only on the outer walls of the building (on the Mauerlat or the upper crown). In order to increase the reliability of the system, so as not to ruin the walls, they are connected by puffs (also called a jumper or crossbar). This type of rafter system is suitable for buildings of small width (less than 10 m) and in cases where there is no load-bearing wall running in the middle.

Two types of truss systems - with hanging and layered rafters

The second type of system is with layered rafters. They rest on a ridge beam and a mauerlat, but the load from the roof is also distributed to the middle load-bearing wall, through vertical bars - girders, which are installed with the same pitch as the rafters and rely on the lower puff.

Do-it-yourself installation of gable roof rafters

For most of the baths, the system is made with hanging rafter legs - the dimensions allow this. In this case, less consumption of lumber and less time is required for its arrangement. In this case, most of the work can be transferred to the ground.

They make one triangle from the rafters according to all the rules and sizes. They try it on, and then make the right amount of its exact copies. Finished rafters with puffs and crossbars, fastened and measured, are raised to the roof. There they are set strictly vertically in the designated places and are fixed to the Mauerlat and the ridge.

An example of how to make a gable roof with hanging rafters, see the video.

With a roof slope length of more than 4.5 meters, to increase the reliability of the system, vertical racks are installed, which support the rafter leg at one end, and rest against the floor beam with the other. This is done regardless of the type of installation of rafters: both hanging and layered. They also install slopes that make the structure even more rigid.

In any case, the rafters will need to be attached to the ridge beam, as well as to the Mauerlat. The figure below shows the mounting options for the ridge.

It will also be necessary to attach the rafters to the Mauerlat. How to do this - see the photo below.

Lathing device

Making a gable roof with your own hands ends with the installation of a crate for roofing material. To do this, a waterproofing film or membrane is rolled out on the outside of the rafters. Lay it in a horizontal direction. Starting from the bottom, moving up. The second and all subsequent rows are laid with an overlap of at least 15-20 cm. They are fixed with small nails or staples from a staple gun.

After installing the truss system, a film or waterproofing membrane is fixed on it, and on top - a crate

There are two ways - with or without a counter-crate. The counter-lattice is stuffed along the rafters, and on top there are already lathing bars. Thus, an air gap is formed between the waterproofing and the roofing material. This option is better from the point of view that such a roof will dry out better and faster. And this is very important for baths.

Without a counter-lattice, the bars are packed immediately over the waterproofing. There is also a gap here, but it is smaller, therefore, ventilation will be worse. But this option is also acceptable: less consumption of materials and work, too.

After the manufacture of the crate, it remains only to fix the selected roofing material.

Results

Now you know how to make a gable roof with your own hands. Of all types, this is the simplest option that a non-specialist can make.

The rafter system is the "skeleton" of any roof structure. The reliability, quality and durability of the roof made directly depends on the correctness of its manufacture and installation. If desired, you can handle the arrangement of the truss system yourself. Do you want to know how? Check out the following guide!

There are layered and hanging truss systems. According to statistics, layered structures are most often used. When arranging such a system, they run into the Mauerlat. The function of the central part is performed by a simple ridge run. To increase the strength of the system, supporting beams are mounted.

In the case of hanging rafters, the design of the system is completed with additional racks that contribute to the optimal distribution of the load over the entire area of the roof structure.

We take an additional pair of nails and fix the angle set between the boards. This template is ready. Additionally fix it with a crossbar. To ensure that the set slope angle of the roof slope does not change under the influence of loads, fasten the crossbar with self-tapping screws.

Be extremely careful when creating a template. Even due to the slightest deviations, the entire structure can deteriorate.

Next, we make a new template for preparing mounting cuts on the system elements. Use plywood 0.5 cm thick. Use a 2.5 cm board for reinforcement. Select the dimensions of the cuts taking into account the cross section of the rafters used.

Using ready-made templates, we make cuts and begin to assemble the farm.

Video - Gable roof truss system

Farm assembly order

The design includes supporting legs and connecting components. The farm looks like a triangle. Perform the work in the specified sequence, and the finished structure will be able to adequately transfer all incoming

The farm can be done on the ground with a further rise up or directly on the roof. The first option is simpler and more convenient to implement.

We assemble the truss truss in the following order. First, we cut the prepared material to the desired size, join the bars with the upper edges and fasten them with screws. To prevent the appearance of cracks in the bonding points, we pre-drill holes in the bars with a diameter slightly smaller than the size of the fasteners.

We also use a crossbar to connect the rafter legs. Fixing is carried out half a meter below the upper point of fastening of the elements. Crossbars will increase the rigidity of the structure and eliminate the risk of deflection. We fasten the crossbar in recesses, previously equipped in the rafters by cutting.

If necessary, the rafters are cut at an angle, if this is required by the features of the equipped roof structure.

Roof truss installation

We install roof trusses in the following sequence:

we mount extreme farms;
fix the central trusses.

When installing extreme trusses, we adhere to the following important rules:

After completing the installation of the outer trusses, we proceed to fixing the central and subsequent structures, if their placement is provided for by the project. The optimal truss installation step is 100 cm.

To fix the central rafter triangle, we use temporary jibs. After the visor is installed, the jibs can be removed. Recommendations for fastening the central and other trusses are the same as in the case of the outer structures.

After installing all the structural elements, we proceed to fixing the battens and further arranging the roofing system: moisture, heat and vapor barrier, as well as installing the selected finishing coating.

Successful work!

Prices for various types of fasteners for rafters

Fasteners for rafters

Video - Do-it-yourself rafters. shed roof

Video - Hip roof. truss system

1.
2.
3.
4.
5.
6.

The roof is of great importance for the integrity of the whole house. Therefore, many are interested in how to properly assemble the rafter system so that it is reliable and does not have to be repaired soon. There are many types of roofs, some of them can be seen in the photo, but single-pitched and double-pitched structures are the most popular. Let's figure out how to make the truss system correctly.

Roof types

Before moving on to how to make a truss system, you need to figure out what the common types of roofs are.

Shed roof - the simplest, even a person who does not have much experience in construction can handle its creation. However, this type of roofing is mainly used in the construction of outbuildings. For residential buildings, gable or mansard (broken) roofs are usually made. These designs are more complex, but you can easily deal with them on your own if you know how to make gable roof rafters and follow all the recommendations of specialists (read: "").

The most reliable roofs are hip ones, they can withstand even huge loads. They are recommended to be done in regions where there is a lot of snow and strong winds often blow. But their design is also very complex, so it is better to entrust their construction to professionals.

A hipped (four-pitched) roof is used in the construction of square buildings; in its design, it is a kind of hip roof.

The most complex roof is a cross. During its construction, complex structural elements are used - valleys (grooves). These diagonal auxiliary rafters are installed as additional elements. When building such a complex roof, haste is unacceptable. Most of the snow accumulates in the area of the grooves, and the reliability of the roof depends on how to make rafters in these places.

Each type of roof consists of rafters and roofing. The rafters are the load-bearing part of the roof, and the roof surface is the enclosing part.

Types of rafters

Before you put the rafters, you need to learn about their design features and decide on the installation option.

There are two types of rafters: layered and hanging .

hanging rafters - these are inclined beams mounted on supports with different heights. The support can be the outer walls of the house (in the case of a shed roof) or both the inner and outer walls (in the case of a gable roof). Rafter legs do not have to be laid in the same plane opposite the slopes. They can be mounted alternately on the ridge run. Alternate laying of rafters in the ridge area makes it possible to create a truss truss. To this end, all parts are interconnected into a single rigid structure.

Materials for rafters

As for the rafters from the boards, they are not heavy, and they are convenient to install. You can easily work with this material on your own without resorting to outside help. Many experts do not advise making connections with nails - it is better to use self-tapping screws. If the work will be carried out with the help of nails, do not forget about the lining and liners.

As for how to build a truss system, it is better to use cuttings to connect racks with a run or a bed.

Do-it-yourself installation of the truss system, in detail on the video:

Rafter system connection options

The rafter system can be connected in three ways:

struts;
racks;
at the same time struts and racks.

How to properly make the rafters depends on the span between the outer walls. A beam of 10x10 centimeters is used to create a ridge run. Lezhen and Mauerlat can be made from logs, hewn them into two edges, or by taking a beam of 10x10 centimeters.

When making a ridge knot, it is necessary to nail special clamps made of steel strip to the Mauerlat and run with large nails, taking into account. You can not use steel clamps, but then you need twists of thick wire with a diameter of 6 millimeters.

Regarding how to make a brick or stone house, then a Mauerlat must be laid on the masonry. For its reliable fastening, it is recommended to place a piece of log or timber about 50 centimeters under each rafter leg. Then they are attached with clamps to metal hooks that were previously installed 30 centimeters below the Mauerlat.

Many people have a question about how to make rafters on the roof of wooden houses. Rafters in wooden buildings are laid on the upper crown of the wall. A plank truss truss can be created using a crossbar or with spans (6-8 centimeters). Its structural elements are arranged as follows. Make a single puff with the help of boards, the thickness of which is equal to the thickness of the rafters. For double tightening, thinner boards are used (thickness from 40 millimeters). For the crossbar and overlays, 30 mm parts are taken.

How to determine the cross section of the rafters

Before you properly lay the rafters, you need to decide on their cross section.

This setting depends on:

span dimensions;
expected load (wind force, weight of snow cover and roofing material);
step and angle of installation of rafters (roof slope).

There is a dependence of the cross section of the rafters on the length of the rafter leg.

It is expressed as follows:

with a step of 300 centimeters, bars with a section of 10x12 centimeters or boards with a section of 6x14, 8x14 or 4x18 centimeters are used;
with a step of 400 centimeters, bars with a section of 10x16 centimeters or boards with a section of 6x20, 8x20 centimeters are used;
with a step of 500 centimeters, bars with a section of 10x20 centimeters or boards with a section of 8x22 centimeters are used.

Roofing must be selected taking into account the slope of the roof. Also, the choice of material for the roof depends on financial capabilities. The greater the angle of the roof slope, the more funds will be required to create the roof - this is due to the increased consumption of materials. However, steep roofs are better at draining rainwater and snow, so they are more reliable and will last longer. But given the huge selection of roofing materials on the market, there will be no difficulties with this.
Creating a truss system for a bath

As for how to make rafters for a bathhouse, it is better to choose a gable roof - then there will be an attic in the building, which can be used to store brooms and other bath accessories (read: ""). Thus, it is desirable to create a truss system for a gable roof, it is easier and more practical.