The location of the rafters on a pitched roof. Shed roof truss system: design and installation features. Construction of the truss system

Shed roofs are quite reasonably classified as the most simple and economical structures. She attracts minimum consumption material and simple construction process. The construction of a single-pitched variant can be the first confident step towards an independent roofer.

However, without observing the technological requirements, there will be no positive outcome even in an elementary matter. In order for the result to please with reliability, you need to know what the shed roof truss system is and what requirements must be taken into account during its construction.

Shed roofs are a faithful companion of household buildings, terraces, garages, attached and detached verandas. So far, they are being built extremely rarely over residential buildings in the expanses of the fatherland, although the number of adherents of modern and high-tech styles is touching with an upward trend.

Despite belonging to the pitched category, shed roofs still cannot be unconditionally called attic: the space under the roof is too small to organize the room. And since it does not make sense to use the attic, then it is not always advisable to separate it from the building with an overlap. Therefore, in practice, builders are one pitched roofs instead of overlapping, spacers and rafter legs are often installed.

Simplistically, the truss frame of a shed roof can be called an overlap laid at an angle or half a layered system, which is much closer to the constructive essence. It is built exclusively from layered rafter legs, i.e. from rafters with reliable supports for the upper and lower heels.

Among the options for supporting the rafter legs of shed roofs are:

Two bearing brick, concrete, wooden walls of different heights. In this case, the rafters of a shed roof rest on the walls through a mauerlat laid in two unconnected strips. Support can be made through a reinforced concrete belt, pre-designed and arranged during the construction of the walls, as well as through the upper rows of timber or log boxes.
One load-bearing wall made of concrete, wood, brick and supports located opposite. It is clear that extensions and sheds are built in this way. The upper edges of the rafters in such cases are supported by steel brackets screwed to the load-bearing wall or to sockets selected in it. The lower heels rest on a harness connecting the support posts.
Two rows of concrete, brick, wooden poles. Both heels of the rafters rest on the harness. Moreover, the supports can simultaneously serve as elements for fastening the skin and forming frame walls.

In private construction, shed structures are most often used if the span they cover does not exceed 4.5 m. Overlapping a more serious span is quite real: for its implementation, it will simply be necessary to strengthen the system with girders, supports, struts.

However, among private owners there are few lovers of such large-scale shed roofs, therefore we will consider the simplest representatives and the principles of their construction. Having dealt with their design, it will be possible to create your own project by upgrading and making additions.

A well-designed project takes into account the need to have a lone slope on the windward side so that the roof is not torn off and carried away by gusty winds.

The average size of the components

For the manufacture of layered rafters, wood and lumber of the 2nd grade are used. Skinned logs will do, plates - the same logs, but hewn on both sides. Timber and pairwise sewn boards are used.

The cross section of the rafter legs for the construction of shed roofs over buildings must be calculated taking into account the weight of the roof, snow and wind loads. The listed values among folk craftsmen are simply added up and entered into one of the many calculation programs, of which there are a little less than a legion on the Internet. In order not to toil with the calculations, we will give the average statistical sections of the rafter legs and related elements used for the construction of shed roofs in middle lane, this is:

Logs and plates hewn from them Ø 180-200mm, timber 100 × 150mm (150 × 150mm) are used for construction roof frame covering a span of 4.5 m or more.
Logs and plates Ø 120-180mm, timber 100 × 100mm are used if it is necessary to cover a span of up to 4.5m.

In both cases, it is permissible to replace the beam with a pair of sewn boards, the dimensions of which will ultimately allow obtaining a beam of the required section.

It should be remembered that a log Ø less than 120mm, plates with a thickness of less than 70mm and boards with a section of less than 40 × 150mm are not used in the construction of roof structures. Even for low-responsibility canopies arranged on sites in the middle lane, the indicated dimensions are the minimum.

If the circuit truss system shed roof predetermines the run device, it is installed parallel to the slopes. It is needed to increase the rigidity of the structure as an additional support system. To fix the run, the supports and the bed are mounted in the same way as dictated. Only the goal is not to form a ridge fracture, but to maintain the plane of a large slope. The purlins of large-span structures are made from a bar 180 × 180mm or from a log Ø 200-260mm. For the manufacture of racks for runs, they take a beam with a side of 120mm or a log 130-200mm in diameter.

Single pitch truss system

The installation step of the rafter legs is determined in accordance with the geometric data of the equipped box. The slopes on which the rafters are to be supported are divided into equal plots so that the distance between the rafters is the same. The breakdown of the slopes for their installation is carried out, taking into account the size and type of materials used:

For rafter legs made of timber, log plates, installation step from 1.5m to 2m.
If the rafters are made of a paired board, the installation step is from 1m to 1.75m.
For rafters from a single board, the installation step is from 0.6m to 1.2m.

The choice of the installation step of the rafter legs of the insulated roof structure is influenced by the size of the insulation. It is very convenient if they are installed between the rafters rigidly, with slight squeezing. This is a very economical solution, because they do not need to be laid in two layers, and heat losses are excluded due to the elimination of the causes of the formation of cold bridges.

Do not forget that with an increase in the recommended distance between the rafters, you will have to reduce the installation step of the crate or even make it solid. Such a choice is not always appropriate in terms of both labor and construction costs. It is better to adhere to technological recommendations and calculate in advance which is more profitable: install one or two less rafters or strengthen the slope sheathing.

As is customary in the construction of pitched roofs, the rafters are attached to crutches driven into a wooden wall or laid in brickwork plugs with anchors. Fixation is made through one rafter leg with twists of annealed wire. The attachment points of the rafter legs to the walls are located 20-30 cm below the Mauerlat. Wire strands can be laid during bricklaying. It is allowed to fasten with brackets to walls made of timber or logs.

Variants of single-pitched truss frames

In order to better assimilate the information, we will analyze several common examples of the construction of truss systems for shed roofs. Consider simple construction projects that a skilled owner can handle.

Construction # 1 - single-pitched garage truss frame

Let's disassemble the device of the truss frame of a shed roof over the garage, the walls of which are made of foam concrete blocks. The reinforced belt recommended by the standards was not filled in, which is why the Mauerlat laying procedure is ahead. In lean-to roof structures it is constructed in the form of two beams laid on walls of different heights.

The process of building a truss system in stages:

Flush with the inner planes of the high and low walls, we lay a beam 100 × 150mm. This is a shed roof Mauerlat. Because the beam will have to be in contact with foam concrete, it is laid on a roofing felt or similar waterproofing gasket. We fasten the beam after about 80 cm with roofing corners 90 × 90, reinforced with a cast jumper. We screw the corners with dowels Ø 14mm.
From a board with a section of 50 × 200 mm, we will make a rafter template. Install it on the Mauerlat so that there is a margin of about 55-60cm on both sides. The stock should be slightly larger than the planned width of the cornice overhangs. Usually it is 40-50cm. We cut off the excess after installing all the rafters.
We mark the points of future cuts on the installed workpiece, not forgetting that the depth of the cut should be no more than 1/3 of the width of the board.
We mark the walls so that the extreme rafters on both sides do not touch the concrete wall. It is desirable that there is a distance of 4-5 cm between wood and concrete.
According to the template, we make rafter legs, install them and fasten them to the Mauerlat with brackets or corners.
From trimming the board we make a filly template, taking into account the width of the overhang. We make all cornice elements according to the template. Then we mount, not forgetting the waterproofing pads between the wooden parts and the concrete wall.
We cut off the excess rafters and nail a wind board with a section of 25 × 100 mm along the perimeter.

Elementary roof structure ready for the garage. It remains to fill the crate under the shed roof covering the installed rafters. It can be continuous or sparse. The installation step of sparse gratings depends on the type of roofing material.

In the first example, we formed the cornice overhangs by mounting fillies. There is a slightly different way, according to which the Mauerlat beams are installed with the removal of the perimeter of the box. Removal is equal to the width of the cornice overhang. The rafters are positioned so that the extreme elements are just above the edges of the Mauerlat. In the space between the extreme and adjacent rafters, short extensions are mounted. Further, everything is according to the standard plan.

Structure #2 - shed roof over extension

No less often than the previous example, the task of building an extension to an existing building arises. For obvious reasons, the roof will be shed. It will perfectly fit into any architectural and landscape conditions, moreover, it will not create a threat of accumulation of precipitation.

The truss system is being built at an angle of 20º, because over it will be produced. The rafters will rest on the main and opposite brick wall of the extension. In our proposed example of a single-slope structure, it is necessary to cover a span of 4.75 m, which is more than 3.5 m. So, to ensure rigidity, the installation of struts will be required. The design and installation of struts are carried out with the condition that their inclination angle is not desirable to exceed 45º.

The cross section of the board for the manufacture of rafter legs is 50 × 200 mm. They will be installed after 70cm. We will make the struts from a board 50 × 150mm, and for the construction of the crate we will stock up on a board 25 × 100mm.

Algorithm for the construction of a single-pitched truss frame:

We install a beam 100 × 150mm flush with the inner plane of the extension wall, not forgetting to pre-lay waterproofing. We fix the beam with bolts through 80-100mm.
In the main wall at the planned height, we hollow out the grooves for the installation of the upper heels of the rafters. The depth of the grooves is 12 cm, the width is slightly greater than the thickness of the board, the step is 70 cm. Instead of slotted grooves, you can use metal brackets that are simply screwed to the wall. In shape, they resemble an inverted letter "P", in which the upper edge of the rafters is located.
Let's make a template for rafter legs. We put the board 50 × 200mm to the place intended for it and mark the cuts from both edges. The depth of the upper cut required to install the rafter into the groove is 10 cm. You don’t need to do it deeper, otherwise the rafter will rest against the wall, and this is undesirable. The dimensions of the upper gash are transferred to the bottom. At the same time, we mark the vertical saw cut line along the width of the cornice.
Using the template, we make all the rafter legs and install them in their proper places. For fastening at the top, we use metal corners, one side of which is screwed to the wall, the other to the rafters. At the bottom we fix with corners or staples.
We try on a piece of board to the main wall and one of the rafter legs to determine the point of cutting the groove under the strut. Do not forget that the angle between the wall and the strut should not exceed 45º, and the lower heel of the strut should rest against the wall 20-30 cm below the opposite wall.
Stepping back from the imaginary vertical line drawn through the upper groove, 5-6 cm in any direction, we hollow out the bottom row of grooves. We place them every 70cm.
We cut the lower corner from the strut blank so that the cut line is 10 cm.
We try on the workpiece by setting the edge with a gash in the lower groove. Along the line of intersection of the rafter leg and the workpiece, we draw the upper washed down.
According to the verified scheme, we make and install all the struts. We fasten them to the rafters with metal gear plates.
We form cornices by installing fillies on the inclined walls of the extension. Do not forget about the mandatory waterproofing between the brick or concrete wall and the roof elements made of wood.
We sheathe the perimeter with a wind board and mount the crate.

The technology given as an example is valid not only for shed roofs over capital outbuildings. Covered verandas with terraces, utility blocks are equipped in a similar way.

Work progresses much more fun if the walls of the main building are made of timber, logs or made according to the Canadian frame method. Brackets are tritely installed under the upper heels of the rafters: there is less trouble and the process moves much faster.

Structure #3 - Shed Structure for Shed

Shed roof - an excellent option for arranging outbuildings, makeshift houses, summer kitchens. Rare units need the fundamental nature of such structures. The simplest options are more actively in demand, with the construction of which the owner of a suburban area can easily handle.

Consider the construction of a shed roof over a small shed for storing country equipment. Its walls are built according to the frame-hothouse principle by installing uprights connected at the bottom along the perimeter by strapping. Front and rear wall the sheds differ in height, therefore they are connected not by a single strapping, but by separate transverse strips.

The crossbar of the high wall is laid at an angle, which makes it possible not to make cuts to support the upper heels of the rafters. To form an angle, the high wall posts are sawn from above at the projected angle.

The algorithm for the device of the truss system is typical. First, a piece of board is applied to the end of the building and cut lines are outlined. Then, according to the template, the required number of rafter legs is sawn. They are installed in the traditional way according to the markings made in advance on the walls. To fasten the elements of the truss system over light household buildings, nails or self-tapping screws are enough. Screw or hammer hardware products at an angle, trying to ensure that there are no gaps between the parts to be joined.

The wind board is fastened around the perimeter after the wall cladding is installed. The example barn has no eaves. However, if desired, they can be made by setting the rafters with a length that takes into account the formation of overhangs. It is planned to lay a soft roof, under which a continuous crate is arranged. The dimensions of the crate made of plywood, GVLV, boards or OSB-3 are determined by the outer plane of the windboard.

The angle of inclination is small, so the use of waterproofing is highly desirable even if the items stored in the barn are not too worried about getting wet. Waterproofing will protect the wooden parts of the building from rotting and subsequent inevitable failure.

Visually, the video will introduce the process of building a truss system for a pitched roof:

We have reviewed the most characteristic examples, relevant and available for hand-written execution. The technological nuances of typical situations were described in detail. it basic options, which may well become the basis for their own developments. Dimensions change in connection with individual needs, but the principles of construction of truss frames for pitched roofs are stable. Knowing them is useful for both independent craftsmen and owners who want to competently control the work of builders.

The shed roof truss system has a number of advantages that make it a good choice for installation on auxiliary buildings, garages, extensions to the main building.

Benefits of a pitched roof

The device of a shed roof on buildings various types beneficial due to a number of factors:

low weight of the structure;
low cost of construction;
simple installation technology;
the possibility of using a wide range of structural and roofing materials;
ease of installation of the drainage system, chimney.

A roof structure with a single slope can be used in the construction of a house to implement original design ideas. In addition, this is a favorite version of the roof frame for outbuildings, garages, baths, sheds and verandas.

When building separately standing garage from bricks, the basis for the installation of roofing material can serve concrete plates or metal structure. But no less often a truss system of wooden elements is erected. Calculation of rafters for small buildings can be done independently, in difficult cases it is recommended to contact professionals.

Rafters: design calculation and material preparation

The scheme for the construction of a shed roof is extremely simple: the rafters cover the span between the end walls of the building. The angle of inclination of the slope is determined by the difference in the height of the walls. Two methods can be used to achieve this height difference.:

the laying of one of the opposite load-bearing walls is carried out to a great height;
special supports are mounted on one of the walls, on which a run is laid to support the upper ends of the rafters.

The first option is most suitable for the construction of a structure from piece materials. The second method allows you to save building materials from which the walls are built.

A roof structure with one slope should have a slope of no more than 50-60 °. The optimal value is considered to be an angle of 18-35 °, but specific parameters should be chosen taking into account various factors. The rafter system must withstand its own weight and high external loads - wind and snow. The intensity of the loads directly depends on the angle of the slopes. In addition, you should pay attention at what values it is possible to install the selected roofing material.

The pitch of the rafters also affects the reliability of the roof. The smaller the step, the higher the calculated load that the roof can withstand. But if the installation step of the rafter legs is unreasonably small, this leads to an increase in the weight of the structure, and, accordingly, the load on the walls and foundation of the building. Too large a pitch of the rafters will not allow you to create a roof that is resistant to external influences.

The design calculation can be done manually, but it is more convenient to do this using a special program. The developed project should reflect not only the pitch, dimensions and sections of the elements, but also the schemes for the execution of the roof frame nodes.

Shed roof rafters for small spans are made of boards or beams. If the span exceeds 4.5 meters, you may need to install elongated rafter legs.

Timber and boards for the manufacture of the truss system of a garage or other structure must be well dried and not have damage that affects the strength characteristics. Before installation, prepared wooden elements must be treated with a fire-retardant compound to protect the frame from accidental ignition and extend its service life.

Garage roof rafter installation scheme

The rafter system of the garage roof during the construction of a shed structure may vary depending on the characteristics of the building. On a small structure, it is enough to simply lay the rafters, resting them on the upper part of the opposite walls, lined with bricks or blocks. If it is planned to build a garage with an attic, then in this case it is necessary to lay beams across the span (step - 1-1.5 m), which will serve as the basis for the floor. The rafters, as in the first case, are attached to opposite walls, but at the same time they are additionally reinforced with struts - this allows you to provide the necessary rigidity of the garage roof frame.

If the building box is made of brick, the laying of the ends of the beams and rafter legs of the shed roof of the garage can be done in special nests provided in the walls. In this case, the fastening of the beams is carried out to long walls, and the rafters - to the end. The high wall should be the wall with the garage door. Waterproofing made of rolled bitumen-containing material is preliminarily laid in the nests.

Wooden rafters for a shed roof can be mounted directly on the walls of the structure if a small span is covered and the rafter spacing is sufficient to receive and distribute the load fairly evenly. In other cases, the rafter legs are attached to the Mauerlat.

The requirements for the Mauerlat are quite simple: it must be strong, durable, firmly fixed on a wall built from piece building materials. Theoretically, the rafters should be fastened to the Mauerlat mounted on the reinforced belt of the wall. But since the garage belongs to buildings with low loads, the support beam for the rafters can be laid directly on the upper edge of the wall and fixed to anchors and rolled wire embedded in the masonry. Mauerlat needs reliable waterproofing made from roll materials.

The armored belt of the wall under the shed roof is made of reinforced concrete. For its arrangement, it is necessary to make a plank formwork, fix the reinforcement in it and install the studs. The height of the embedded fasteners should allow in the future to lay a Mauerlat beam on top of the monolithic beam with a pre- drilled holes under the studs and fasten with nuts equipped with wide washers.

If a garage or other building is built from timber or logs, the function of the Mauerlat is performed by the upper trim of the log house. The installation step of the rafter legs on a shed roof is most often 60-70 cm - this parameter makes it possible to use almost any piece or roll material for the roof, provided that the crate of the appropriate type is installed.

In order for the rafter system to make it possible to equip a roof that can protect building structures from the effects of precipitation, the rafter legs must protrude 30-40 cm beyond the edge of the wall, forming an overhang.

Installation of the extension roof

A residential or commercial extension is a building adjacent to the main building. Most often, a shed roof is erected over it, adjacent to the wall of the main building or its roof. Fastening the rafters of a shed roof of an extension differs to some extent from installation roof frame in a separate building. The main difference concerns the installation of the upper part of the rafters - the lower ends of the rafter legs are attached to the Mauerlat or a special support using standard methods.

Before erecting a shed roof extension, it is important to determine the required angle of inclination of the slope. In accordance with the obtained value of the required difference between the front wall of the extension and the back wall, a wooden structure is mounted from a beam with a cross section of at least 150 × 150 mm. Special attention it is necessary to pay attention to the connection of the frame for the rafters with the wall of the main building.

Rigid fastening is not recommended, since adjacent buildings may have different shrinkage rates, which over time will lead to the formation of cracks in the walls. The device of such a bundle usually involves the use of an elastic layer between the support beam for the rafters and the wall. The beam can be laid on columnar supports or a frame made of timber. The gap of 2-3 cm between the beam and the wall (expansion joint) should be filled with polyurethane foam or other elastic material with low thermal conductivity. It is allowed to fasten the beam to the wall by means of anchors.

If it is required that the roof of the extension adjoins not to the wall, but to the roof of the main building, it is advisable to think in advance what technology will be used to install the truss system. To ensure maximum reliability of the shed roof of a new building, it is recommended to completely dismantle the adjacent roof slope of the main building in order to install new rafter legs from the ridge of the main roof to the extension Mauerlat. It is necessary to provide for the release of the rafters beyond the plane of the extension wall for the installation of a cornice. Another option involves connecting the rafters of the extension to the rafters of the main roof at a certain distance from its ridge. In this case, the device for adjoining roofs requires the dismantling of only part of the slope of the main roof.

When choosing the angle of inclination of the roof of the extension, you should pay attention to the following points:

the greater the angle of inclination of the rafters, the less the danger of accumulation of rainwater or snow mass that has “moved out” from the main roof;
the rafters of an extension located on the south side may have a smaller slope than that of a similar structure on the north side, because. the sun promotes intensive evaporation of moisture.

Wooden rafters for a shed roof are sensitive to moisture. The places where the rafter legs adjoin the wall or main roof should be carefully sealed - for this purpose, a roof apron is installed.

Shed roof truss system: how to install, fastening, device

The device and fastening of the truss system for a shed roof. Design, installation and selection of rafter pitch for a shed roof of a house, garage or extension.

Fastening the rafters of a shed roof: a thorough analysis of the units used

The tempting simplicity of the roof with a single slope inspires thoughts about the opportunity to prove oneself in the field of a successful builder. The construction of an unpretentious design consists in the banal laying of rafter legs on the supporting walls. No complicated knots, intricate and numerous connections. However, even in the simplest carpentry, there are tricks that require thorough study. The future performer needs to know firmly how the shed roof stacks are fastened in order to exclude deformation and damage to the elements of the frame system.

Traditional "wooden" troubles

The scheme of the truss frame of a pitched roof is extremely simple. It is a series of parallel-laid boards or beams, resting their edges on two walls of different heights. For installing and attaching rafter legs to building structure a transitional element made of wood is used.

Depending on the type of box to be equipped and the material of the walls, the function of the transition element is performed by:

Mauerlat. In a shed roof scheme, these are two separately laid wooden beams that complete concrete or brick walls.
Top harness frame structure. Mounted on top of the racks of the frame is a belt made of double-stitched boards or timber.
The upper crown of the foot, made of timber or logs.

The rafter legs and the elements in contact with them are made of wood, which has the ability to change its own dimensions following fluctuations in the humidity background and temperature changes. In spring and autumn, especially during the rainy season, the length of the rafter legs will be somewhat longer than in dry summers and frosty winters.

Imagine what will happen if the rafter, rigidly fixed at the top and bottom, increases in size. Gaps will appear in the waterproofing, fasteners will loosen, slate sheets will move, metal tiles will move. In addition, the deflection and heaving of the roof frame will certainly affect its wear resistance.

However, changes in the linear dimensions of the rafters are not at all the main hitch of wooden truss systems. An unpleasant surprise, if not taken into account, will be the sediment of a newly built box.

It is most pronounced near wooden walls, but it is also very typical for structures made of concrete and brick. Recall that shed roofs rest on walls of different heights. Without calculations, you can understand that they will drop by different values. Those. there is a threat that, due to the difference in the subsidence of the walls, the new roof will not just change the angle of the slope. There will be a possibility of violation of nodes with extremely negative destructive consequences.

Despite the simplicity of shed roofs and the direction of laying rafters close to the horizontal, the listed risks must not be forgotten. The knots used in fastening the rafter legs of a shed roof must take into account the "whims" of the wood.

The work of the developer of his own shed roof project is to find the right solution for three important tasks, according to which:

It must be possible to move wooden parts relative to each other.
All should be excluded probable causes connection failures.
It is necessary to give the rafters the opportunity to adapt to the effects of wall subsidence so that they can take a stable position.

The rafter legs of shed roofs erected over walls of equal height are classified as layered. The hanging type is used if the equipped box has walls of equal height, and the slope is formed by rafter triangles.

With the fastening of triangles, everything is clear: with the horizontal side they are installed on the harness or Mauerlat, they have the maximum docking area with the supporting elements, and are fixed in the usual way.

With layered rafter legs, everything is much more complicated. They are installed at an angle to the supporting elements. Without processing and preparation for installation, the rafters have only two unreliable points of contact with the strapping or Mauerlat.

No matter how powerful the fastener is, two points are not enough for a solid fit of the part. Even with a slight impact, such a slope will simply slide down along with a continuous crate and a multi-layer roofing cake. However, there are methods invented by ancient builders to avoid such troubles.

In order to prevent unwanted movements, the contact area of \u200b\u200bthe rafter and the supporting element is increased, for this the following is done:

A selection of notches. These are cuts in the form of a triangle or a triangle with a tooth. They are cut out exclusively on the rafters, so as not to weaken the supporting Mauerlat.
Washed down the upper or lower edge of the rafter leg, which creates a support platform that increases stability. It is carried out strictly vertically or horizontally.

Depending on the type and place of sawing or trimming, cuts and cuts may or may not restrict the movement of a wooden part. Restrictions are considered relative, because there are no absolutely rigid fasteners in the construction of pitched roofs. Specialists classify the used nodes according to the degrees of freedom: from one to four.

In the construction of roofs with one slope most often appear:

Single degree of freedom tie-downs are virtually fixed joints that allow the rafter to rotate slightly around the tie-down point.
Two-DOF fasteners are joints that allow rotation around the fastener and slight horizontal movement.
Mounting points with three degrees of freedom - connections that allow rotation and displacement horizontally and vertically.

The presence of degrees of freedom does not mean at all that the rafter will be able to freely rotate and move around the node. They are fastened quite rigidly, because they have to hold the crate, corrugated board or other type of coating, snow cover.

The connection will show its own capabilities only if the load is exceeded. Then the rafter legs will just move and take a new position, and the system will remain undamaged.

Any shed roof scheme clearly depicts the presence of at least two connecting nodes. We divide them conditionally into upper and lower. In construction roof rafters the rule applies: if one of the nodes is fixed rigidly, then the second should have more opportunities for movement.

Projecting and simplifying the technological principle, we can say: if the fastenings in the upper nodes of a pitched roof are rigid, then the lower connections should be looser in order to allow displacement when the pressure is exceeded. And vice versa: if the lower mount is practically motionless, then at the top the rafter must be provided with some kind of reserve for movement and rotation.

Details about the knots of a pitched roof

After getting acquainted with the theoretical side of the issue of fixing the rafters of a shed roof, you can proceed to practical research on the demanded nodal schemes. Note that most projects of systems with a single slope are designed for the installation of rafters that form overhangs due to their own length. However, when covering large spans, it happens that there are not enough standard sizes of lumber. In these cases, fillies are sewn to the rafters, creating an overhang. They are installed on the side of the installed leg and do not affect the principle of knot formation at all.

The second reason for using fillies in the formation of overhangs is the too heavy rafter, which is very difficult to lift and install. The third prerequisite lies in the features of nodal fastenings: if the lower heel is installed on a slider with a trimmed edge.

No. 1: Support at the top and articulated bottom

A scheme with a rigidly fixed top and a relatively movable bottom is used in the construction of roofs over extensions, in the construction of objects with a steep roof and a significant difference between the height of the supporting walls.

Simply put, where the upper edge of the rafter rests against a wooden beam, a run or wall of the main building and no space is left for it to move. The lower node in such situations is calculated on the slider, which allows it to move slightly.

Algorithm classic version with the top resting on the run:

We install the supports of the running frame. On the strapping of the frame building on opposite sides, we install supports sewn from three pieces of board 25 × 100. The middle segment should be 75mm shorter than the extreme ones in order to form a kind of notch.
We build a running frame. We put a board 25 × 150 of the required length in the recess.
We apply a board 25 × 100 of arbitrary length to the end of the future roof, but more diagonal, drawn from the top of the running frame to the strapping, by about 30 cm. We mark the vertical line of the upper gash, outlining the adjacent edge of the run. We mark the line of the lower gash and the vertical for trimming the edge of the rafter.
We cut out the rafter according to the marks, try it on in fact, if necessary, correct the cuts.
According to the made template, we cut out and mount the rafter legs.

We select the type of fastener based on the expected load. It is more convenient to fix the top with corners, the bottom - with corners, by screwing no more than three self-tapping screws into them, or with sliding supports. If necessary, the lower knot can be stabilized - sew a support bar to the bottom of the rafter leg.

The connection node with the run can be designed a little differently: the rafter is laid on the beam using a notch. Here the groove is selected strictly according to the size of the material. But if it is necessary to increase the degree of freedom, the horizontal wall of the cut is beveled at a slight angle, and the lower unit is equipped with a sew-on bar.

No. 2: Top and bottom are hinged-fixed

The scheme is applicable when arranging boxes whose walls have already undergone intensive shrinkage. Suitable for isolated objects. The upper node is made in the form of a triangular cut, the lower one is in the form of a gash with a tooth resting on the Mauerlat.

The process of building a shed truss system:

We install the blank board with an edge on the Mauerlat bars anywhere on the roof.
Lay a well-trimmed piece of board flat on the lower Mauerlat. We put it so that the extreme edge coincides with the inner edge of the Mauerlat. Having outlined the cut, we obtain the outline of the lower attachment point.
We transfer the cut to the area of \u200b\u200bthe upper cut and outline it, because the lower heel of the rafter will drop by this amount.
The blank with the knots drawn and then sawn out will serve as a template. Using it, we make the number of legs specified by the project.
We install rafters. We fix at the bottom with staples or hairpins, at the top with corners.

If you need to increase the degree of freedom, by analogy with the previous method, the vertical edge of the upper notch will need to be slightly beveled. The cutting angle will then not be 90º, but 95 - 97º. Experienced carpenters make simple cuts directly on the object, turning the workpiece upside down. Novice performers should not imitate in the early stages.

The rafter template is used in roof construction only when there is no doubt about the geometric characteristics of the box. In reverse situations, the rafters are tried on and made individually. First, the extreme elements of the system are installed, then ordinary legs are stretched between them.

One of the variations on the theme of two hinged-fixed nodes involves the device of a vertical gash at the top and a cut with a tooth at the bottom. Work on their device is carried out as follows:

We install the blank board on the Mauerlat so that its lower corner is directly above the outer edge of the beam.
At the top, using a piece of board, mark the vertical line washed down (x) and measure its length.
We transfer the length of the upper gash to the region of the lower node. Set aside the length of the gash (x) up vertically from the inner upper edge of the Mauerlat.
From the resulting point, draw a horizontal line. The result is a cut with a tooth.
We cut out the nodes according to the marks, set them in place, fasten them with corners, duplicate the lower nodes with brackets.

With an increase in the size (x), the slope of the roof will increase, with a decrease it will decrease.

No. 3: Free top and hinged bottom

An ideal scheme for the construction of a shed roof with rafters, the edges of which are released beyond the walls. After some adjustment, it can be used in the arrangement of outbuildings.

We install the workpiece with an edge on the upper and lower Mauerlat beam with the removal of the edges beyond the walls. Here you need an assistant to hold the board to the canopy.
We apply a template - a trimmed board cut sequentially to the lower and upper Mauerlat so that the outer edge of the template coincides with the outer edge of the bars. We mark the lines of the upcoming cuts.
We select cuts according to the outlined lines. The vertical wall of the upper cut is slightly bevelled.
We install the rafter, fix it at the top with nails or corners, at the bottom with brackets.
We manufacture and install the remaining rafters in the same way.

It is clear that mobility with its antagonist is a relative concept. However, they should not be taken lightly. It is required to take into account the degree of freedom of the node both during the design period and when choosing fasteners. The lack of mobility of the structure will lead to deformation, the excess will contribute to instability.

No. 4: Mobility of both mounts

A scheme with two movable nodes can be used if both fasteners have no more than two degrees of freedom. Those. mixing horizontally exclude restrictive devices installed at the top and bottom.

Consider an example in which the rafters of the extension are laid at the top into niches cut in the wall. Means, horizontal offset is excluded, rotation and some vertical movement are possible. The bottom is planted with the help of cuts, but in the horizontal direction it is limited by metal corners.

The actions of the builder of the "single-roll" step by step:

We prepare the object for work. We put a mauerlat made of 100 × 150 timber on the brick wall of the extension. We lay it on the wide side closer to the inner edge of the wall. We fasten with anchors after 80 cm. In the main wall of the building at the design height, we cut out the grooves for the upper heels of the rafters. The depth of the cuts is 12 cm, the step between them is 70 cm. If you do not want to mess with gouging, you can use metal brackets screwed to the wall.
We make a template for the rafter leg. We set the blank board with the upper edge in the groove, the lower on the Mauerlat. Departing from the lower corners of the workpiece 10 cm in the horizontal direction, we draw two triangular cuts.
According to the indications of the template, we make rafters. We install them, fix the position with metal corners.

The device method is valid for overlapping spans up to 4.5 m. If you need to cover a larger span, the rafters will need a support group as part of the struts.

No. 5: Rigid attachment to the sloped harness

The method is applied in frame construction, because it is possible to lay the support element at an angle only on racks sawn at an angle. Either the racks of the frame itself, or the cantilever-running structure mounted on the box, are sawn obliquely. In principle, the latter option is quite suitable for the construction of a shed roof on concrete and brick walls.

Stages of the device of a shed roof along an inclined strapping:

We assemble the structure that creates the slope of the roof. On the gable side of the frame building, we mount short racks with an upper edge sawn at an angle.
On the sloping top of the racks, we lay the board in one row for small outbuildings, in two for more serious houses.
We equip the end sides of the roof with frames in the form right triangle, the hypotenuse of which should repeat the slope line.
We apply the rafter to the end of the roof to mark the line of the lower gash.
We make according to the template required number rafter legs. We install them on the harness, fix the position of the elements with metal corners.

Without a shadow of doubt, we will classify the latter method as the simplest one. Of all the ways of attaching rafters to the strapping and Mauerlat beams of a shed roof, this one is the most conducive to attempts at self-implementation.

Final fixing work

After installing the entire row of rafter legs, we check the design position of the elements, the distances between them. We apply an arbitrary board flat to the ramp frame, identify flaws and correct flaws. Then we fasten the rafters with brackets or bundles to the walls through one in regions with medium and low wind activity. We fix each leg in areas with high wind load.

Filly, if they are planned for installation, are made of material with dimensions half as large as the dimensions of the rafter legs. Sew them on the side to the rafter. The length of the sewn section is on average 60-80cm.

The presented methods and schemes for fastening the rafters of a pitched roof have been tested by practice. They are used most often in a "pure form". However, some adjustments according to specific specifications are not excluded.

A shed roof is simple, economical in terms of material costs, and the minimum number of nodes is used during installation. We have a shed roof at the garage and gazebos on the site. Such a roof weighs little, the choice of material for the coating device is practically inexhaustible, it tolerates wind and precipitation well, does not flood neighbors nearby (but a good drainage system is needed).

Yes, in terms of material, a single-sided design is more economical, and also less labor-intensive. I would also like to add that the dismantling of such a roof is also simple, in comparison, for example, with a gable roof. Of the minuses, I can only name that if the roof is used on a garage or a bathhouse, a shed, then with the raised side it should look towards a higher building, for example, a house. And the building will be less exposed to winds, and even after rain, if a drainage system is not provided, water will not be poured into the house.

Attaching the rafters of a shed roof: step by step instructions from the masters

Properly executed fastening of the rafters of a shed roof will ensure the stability of the structure, the reliability of the nodes guarantees a long service life without problems.

Shed roof rafters: details and installation details

A roof with a slope on one side has always been popular due to its obvious simplicity and minimal cost. The sloping rafters of a shed roof, with two ends resting on load-bearing walls of different heights, inspire much less concern in strength and stability than a complex system rafters of gable roofs.

The correct choice of the location of the roof relative to the prevailing wind direction will help to ensure its maximum service life. It is equally important to choose the right slope.

A roof structure with one slope is most readily used for:

At the same time, they always strive to orient the slope of a shed roof in such a way that its low part is located towards the prevailing winds. This greatly reduces the impact of wind and other atmospheric phenomena for the entire building. When installing a shed roof with your own hands, never forget about it.

Many are sure that the installation of a shed roof truss system is not at all difficult, and untrained people can assemble it.

It is quite possible, but when performing work on the roof, everyone needs to follow the safety rules - both professionals and amateur enthusiasts. This requires, at a minimum, strong ladders, mounting belts and strong ropes.

The shed roof scheme is really not very difficult for a person with minimum set technical knowledge, but “hatting” is absolutely inappropriate here. Thoughtlessly executed shed roofs of a garage, a utility block, and especially a residential building, can bring a lot of trouble and disappointment to the owner.

Wooden trailer with pitched roof

Roofing failure by a gust of wind, massive leaks or roof deflections from accumulated snow can spoil the mood of any person for a long time.

We hope everyone has already understood how serious it is - the installation of a pitched roof. However, subject to a few rules and the manifestation of creative thought, it is quite possible as a result of your efforts to get something quite acceptable in terms of design and functionality.

The design of pitched roofs is divided into two types:

Do-it-yourself non-ventilated version of a shed roof is mainly used in annexes-terraces. For practical use roof area (arrangement of flower beds, fountains, small pools), the slope is chosen small - from 3 to 6%. However, such a farm requires special care in anticipation of the winter season.

Ventilated shed roofs are usually arranged with slopes ranging from 5 to 20%. Under the cornices on both sides of the roof, special holes are made for ventilation. The presence of a ventilated space between the waterproofing and the insulation prolongs the life of the building. In some cases, a combined roof option is chosen, where the slope is set by a variable thickness of the heat-insulating layer.

The low pitch angle of a pitched roof is beneficial in terms of material costs and the practical use of its area, however, there is a high risk of accumulation of large masses of snow in winter. This means regular cleaning of the roof, its damage, subsequent leaks and the constant risk of falling from a height.

When building a country house, installing a shed roof will significantly save money when buying building materials and paying for installation.

Shed roof rafters

Shed roof truss system

The purpose of the truss system is to redistribute the weight of the roof to the main walls with all the loads acting on it, permanent and temporary (from snow, wind, precipitation).

The truss system of a shed roof is its original skeleton, its supporting frame.

The calculation of a shed roof during design should take into account all loads with a multiplying factor. If in recent years there has been a tendency towards an increase in the peak values of one-time precipitation or storm winds, then it would be useful to take this into account in the calculation.

At the same time, it will be fair to note that, due to their low windage, single-pitched roofs experience less wind load than their multi-pitched modifications.

If you are interested in a sloping shed roof, then you need to know that its constructive solution will be made up of:

the location of the supporting walls;
type of attic floor;
the presence of internal walls;
the size and configuration of the building;
span span.

According to the method of support and the method of fastening, the rafters are divided into:

Sliding rafters with their top rest on a ridge log, and are attached to the walls with special metal corners with a movable “sliding” plate. Sliding types of rafters are usually used in log houses, where the shrinkage of wood during the drying of the log house is very significant (up to 5% of the volume of wood).

The shrinkage stresses are so great that they would easily break the rigid fastening of the elements. The danger is not so much the shrinkage itself, but its unevenness. Therefore, the "sliding" plates fixed to the rafters have a power reserve in the lugs of the corners attached to the wall.

The external walls of the building serve as a support for inclined rafters (rafter legs). With their connected upper part, they rest on a ridge beam supported by uprights and struts. The inner walls serve as the base for the struts and struts.

The step between the truss systems is assigned in the range from 0.6 to 1.4 m.

How more sizes roofs and its mass, the rafter legs are installed with a smaller step. The cross section of the rafters is selected taking into account the weight of the roofing and snow load. Each drawing of a shed roof must contain indications of the size of the sections of all elements of the truss system. After the installation of the inclined rafters is completed, a crate is attached to them ( see video below), which is the basis for roofing.

If you carefully study the drawing of a shed roof with inclined rafters, then it becomes obvious that there is additional support for struts and racks on the inner wall. When the span is large enough, and intermediate supports there are no rafters, then hanging rafters are used - the most difficult type of rafters to perform.

They are a triangular structure assembled in one plane, including two rafter legs connected at the top point and a horizontal lower puff. She ties the lower ends of the rafter legs. It is thanks to the tightening that the rafters do not create spacer loads on the walls, transferring only vertically directed pressure from the weight of the roof to them.

Therefore, for hanging system rafters, a Mauerlat device is optional, which simplifies and reduces the cost of installation.

Still on earth "triangles" hanging rafters they are connected in pairs, fastening the legs with lathing bars, and screeds with attic floor boards. Then each volumetric truss assembled in this way is lifted up and placed in the design position on the load-bearing walls.

Details of truss structures are usually made of wood. conifers(pine, larch). For rafters usually used edged board 200x50 or 150x50 mm, and for the crate - a bar 50x50 mm.

Shed roof schemes

What properties of shed roofs make them attractive in the eyes of potential builders?

Firstly, the construction of a shed is the most budget option of the possible types of roofs. The consumption of wood for its construction is almost 3 times less than for a gable roof. This factor is of particular importance in the southern treeless regions of Russia, where timber is expensive and scarce.
Secondly, roofs with a slight slope experience less wind loads due to low windage. The absence of an attic gives the room an additional volume that can be used with great efficiency. The possibility of using non-standard approaches and original design solutions made projects of houses with a shed roof in demand.

As for all kinds of household buildings, garages, warehouses, a shed roof has been chosen for their construction for more than a century.

Photo: shed roof rafter schemes

Each roofing material has a specified minimum roof pitch:

bituminous roll materials ≥ 5 degrees;
metal tile ≥ 25 degrees;
shingles ≥ 20 degrees
slate ≥ 20 degrees;
corrugated board ≥ 20 degrees;
tiles natural or cement ≥ 35 degrees;
areas with high humidity and heavy snow cover ≥ 40 degrees.

Don't forget that the most efficient shed roof is a ventilated design.

A ventilated under-roof space with regular air exchange prolongs the life of the building, prevents the formation of condensate.

Roofing material is chosen according to your taste, focusing on the nature of the building.

If you are not sure that you can independently calculate the rafters of a shed roof and correctly fasten the rafters of a shed roof to the supports, seek the advice of professionals.

Remember that the fastening of the roof to the house must be not only strong, but also movable, “sliding”. A properly executed roof will always protect you from bad weather.

Do-it-yourself shed roof

Given the low complexity of the design, a shed roof is often taken to be done independently. You need to start with calculations of the angle of inclination, the main parameter of the roof. The large slope provides good stock rainwater and the rapid release of the roof from snow in the spring. However, the wind load on the roof structures also increases.

When choosing a small angle of inclination of the roof, the windage decreases, but the risk of snow accumulation and leaks increases. All this should be taken into account in the calculations. And more importantly, what do you prefer: spending money, shoveling snow, or spending free time for patching the roof.

The choice of roofing is also important:

For a profiled sheet, the slope should be more than 20 degrees. Otherwise, the mass of snow can push through the coating.
For metal tiles - at least 25 degrees to reduce the load on the crate and rafters. When the angle of inclination is calculated, it is possible to calculate the difference in the height of the walls, which will provide this inclination.

The frequency of the rafters and the step of the crate depend on the material you choose and its weight. The frame of the rafters must be made only from sanded wood of air-dry moisture. In addition, all wood parts must be impregnated antiseptics and flame retardants.

All parts are treated with fire-fighting and bioprotective compounds in advance, before installation, and only then the rafters are assembled. Often, additional processing of joints and tie-ins on the roof is carried out at the place of work.

Having completed the complete assembly of the rafters and lathing, proceed to the roofing device:

waterproofing layer. Provides maintenance in a dry condition of wood and prolongs service life of rafters;
The laying of the roof covering begins with the eaves of the rafters, moving towards the ridge. Each subsequent row of material is laid “overlapped” on the previous one, strictly maintaining the required overlap;
In the process of work, it is necessary to constantly check the tightness of the elements to each other and their tightness.

Now you probably know everything about rafters and how to make a roof with your own hands.

Shed roof rafters (photo): accurate calculation, device diagram, angle of inclination of the rafters

The article “Shed roof rafters” will tell you about the basics of calculating the structure and the angle of inclination of the roof truss system, as well as explain the rafter scheme.

Shed roof truss system: device rules and analysis of typical options

Shed roofs are quite reasonably classified as the most simple and economical structures. It attracts with minimal material consumption and a simple construction process. The construction of a single-pitched variant can be the first confident step towards an independent roofer. However, without observing the technological requirements, there will be no positive outcome even in an elementary matter. In order for the result to please with reliability, you need to know what the shed roof truss system is and what requirements must be taken into account during its construction.

One slope in low-rise construction

Despite belonging to the pitched category, shed roofs still cannot be unconditionally called attic: the space under the roof is too small to organize the room. And since it does not make sense to use the attic, then it is not always advisable to separate it from the building with an overlap. Therefore, in practice, the builders of shed roofs often install spacers and rafter legs instead of overlapping.

Among the options for supporting the rafter legs of shed roofs are:

Two bearing brick, concrete, wooden walls of different heights. In this case, the rafters of a shed roof rest on the walls through a mauerlat laid in two unconnected strips. Support can be made through a reinforced concrete belt, pre-designed and arranged during the construction of the walls, as well as through the upper rows of timber or log boxes.
One load-bearing wall made of concrete, wood, brick and supports located opposite. It is clear that extensions and sheds are built in this way. The upper edges of the rafters in such cases are supported by steel brackets screwed to the load-bearing wall or to sockets selected in it. The lower heels rest on a harness connecting the support posts.
Two rows of concrete, brick, wooden supports. Both heels of the rafters rest on the harness. Moreover, the supports can simultaneously serve as elements for fastening the skin and forming frame walls.

A well-designed project takes into account the need to have a lone slope on the windward side so that the roof is not torn off and carried away by gusty winds.

The average size of the components

For the manufacture of layered rafters, wood and lumber of the 2nd grade are used. Skinned logs will do, plates - the same logs, but hewn on both sides. Timber and pairwise sewn boards are used.

Logs and plates hewn from them Ø 180-200mm, timber 100 × 150mm (150 × 150mm) are used for the construction of a truss frame covering a span of 4.5 m or more.
Logs and plates Ø 120-180mm, timber 100 × 100mm are used if it is necessary to cover a span of up to 4.5m.

In both cases, it is permissible to replace the beam with a pair of sewn boards, the dimensions of which will ultimately allow obtaining a beam of the required section.

If the scheme of the truss system of a shed roof predetermines the run device, it is installed parallel to the slopes. It is needed to increase the rigidity of the structure as an additional support system. To fix the run, the supports and the bed are mounted in the same way as the technology for constructing gable roofs dictates. Only the goal is not to form a ridge fracture, but to maintain the plane of a large slope. The purlins of large-span structures are made from a bar 180 × 180mm or from a log Ø 200-260mm. For the manufacture of racks for runs, they take a beam with a side of 120mm or a log 130-200mm in diameter.

Single pitch truss system

The installation step of the rafter legs is determined in accordance with the geometric data of the equipped box. The slopes on which the rafters are to be supported are divided into equal sections so that the distance between the rafters is the same. The breakdown of the slopes for their installation is carried out, taking into account the size and type of materials used:

For rafter legs made of timber, log plates, installation step from 1.5m to 2m.
If the rafters are made of a paired board, the installation step is from 1m to 1.75m.
For rafters from a single board, the installation step is from 0.6m to 1.2m.

The choice of the installation step of the rafter legs of the insulated roof structure is influenced by the size of the insulation. It is very convenient if the thermal insulation boards are installed rigidly between the rafters, with slight squeezing. This is a very economical solution, because they do not need to be laid in two layers, and heat losses are excluded due to the elimination of the causes of the formation of cold bridges.

As is customary in the construction of pitched roofs, the rafters are attached to crutches driven into a wooden wall or corks with anchors embedded in brickwork. Fixation is made through one rafter leg with twists of annealed wire. The attachment points of the rafter legs to the walls are located 20-30 cm below the Mauerlat. Wire strands can be laid during bricklaying. It is allowed to fasten with brackets to walls made of timber or logs.

Variants of single-pitched truss frames

Construction # 1 - single-pitched garage truss frame

Let's disassemble the device of the truss frame of a shed roof over the garage, the walls of which are made of foam concrete blocks. The reinforced belt recommended by the standards was not filled in, which is why the Mauerlat laying procedure is ahead. In shed roof structures, it is constructed in the form of two beams laid on walls of different heights.

The process of building a truss system in stages:

Flush with the inner planes of the high and low walls, we lay a beam 100 × 150mm. This is a shed roof Mauerlat. Because the beam will have to be in contact with foam concrete, it is laid on a roofing felt or similar waterproofing gasket. We fasten the beam after about 80 cm with roofing corners 90 × 90, reinforced with a cast jumper. We screw the corners with dowels Ø 14mm.
From a board with a section of 50 × 200 mm, we will make a rafter template. Install it on the Mauerlat so that there is a margin of about 55-60cm on both sides. The stock should be slightly larger than the planned width of the cornice overhangs. Usually it is 40-50cm. We cut off the excess after installing all the rafters.
We mark the points of future cuts on the installed workpiece, not forgetting that the depth of the cut should be no more than 1/3 of the width of the board.
We mark the walls so that the extreme rafters on both sides do not touch the concrete wall. It is desirable that there is a distance of 4-5 cm between wood and concrete.
According to the template, we make rafter legs, install them and fasten them to the Mauerlat with brackets or corners.
From trimming the board we make a filly template, taking into account the width of the overhang. We make all cornice elements according to the template. Then we mount, not forgetting the waterproofing pads between the wooden parts and the concrete wall.
We cut off the excess rafters and nail a wind board with a section of 25 × 100 mm along the perimeter.

The elementary truss structure for the garage is ready. It remains to fill the crate under the shed roof covering the installed rafters. It can be continuous or sparse. The installation step of sparse gratings depends on the type of roofing material.

Structure #2 - shed roof over extension

The truss system is being built at an angle of 20º, because a metal tile will be installed on top of it. The rafters will rest on the main and opposite brick wall of the extension. In our proposed example of a single-slope structure, it is necessary to cover a span of 4.75 m, which is more than 3.5 m. So, to ensure rigidity, the installation of struts will be required. The design and installation of struts are carried out with the condition that their inclination angle is not desirable to exceed 45º.

Algorithm for the construction of a single-pitched truss frame:

We install a beam 100 × 150mm flush with the inner plane of the extension wall, not forgetting to pre-lay waterproofing. We fix the beam with bolts through 80-100mm.
In the main wall at the planned height, we hollow out the grooves for the installation of the upper heels of the rafters. The depth of the grooves is 12 cm, the width is slightly greater than the thickness of the board, the step is 70 cm. Instead of slotted grooves, you can use metal brackets that are simply screwed to the wall. In shape, they resemble an inverted letter "P", in which the upper edge of the rafters is located.
Let's make a template for rafter legs. We put the board 50 × 200mm to the place intended for it and mark the cuts from both edges. The depth of the upper cut required to install the rafter into the groove is 10 cm. You don’t need to do it deeper, otherwise the rafter will rest against the wall, and this is undesirable. The dimensions of the upper gash are transferred to the bottom. At the same time, we mark the vertical saw cut line along the width of the cornice.
Using the template, we make all the rafter legs and install them in their proper places. For fastening at the top, we use metal corners, one side of which is screwed to the wall, the other to the rafters. At the bottom we fix with corners or staples.
We try on a piece of board to the main wall and one of the rafter legs to determine the point of cutting the groove under the strut. Do not forget that the angle between the wall and the strut should not exceed 45º, and the lower heel of the strut should rest against the wall 20-30 cm below the opposite wall.
Stepping back from the imaginary vertical line drawn through the upper groove, 5-6 cm in any direction, we hollow out the bottom row of grooves. We place them every 70cm.
We cut the lower corner from the strut blank so that the cut line is 10 cm.
We try on the workpiece by setting the edge with a gash in the lower groove. Along the line of intersection of the rafter leg and the workpiece, we draw the upper washed down.
According to the verified scheme, we make and install all the struts. We fasten them to the rafters with metal gear plates.
We form cornices by installing fillies on the inclined walls of the extension. Do not forget about the mandatory waterproofing between the brick or concrete wall and the roof elements made of wood.
We sheathe the perimeter with a wind board and mount the crate.

The technology given as an example is valid not only for shed roofs over capital outbuildings. Covered verandas with terraces, utility blocks are equipped in a similar way.

Structure #3 - Shed Structure for Shed

Consider the construction of a shed roof over a small shed for storing country equipment. Its walls are built according to the frame-hothouse principle by installing vertical posts connected at the bottom along the perimeter with a strapping. The front and rear walls of the barn differ in height, so they are connected not by a single strapping, but by separate transverse strips.

Shed roof truss system: device, diagram, instructions

device rules, typical schemes and technological principles, according to which the shed roof truss system is built, guarantee an excellent result

Shed roofs are successfully used in the construction of household buildings: garages, sheds, sheds, terraces and gazebos. It's practical and economical way protect the building from precipitation, wind and cold. However, a shed roof device is also suitable for private houses.

With this building solution, architects create bold design projects with several slopes of varying heights. A huge plus of roofs consisting of a single slope is its accessibility to the general population of homeowners due to the low price of the materials used and the ease of installation.

This article will tell you what the structure looks like, how to calculate the slope of the slope and build it yourself.

shed roof

Shed roof composition

Most often, the term "single" means a roof that has one slope. The slope, the slope of which is set by a simple truss system, rests on the load-bearing walls of the building and internal partitions, if any.

Used as roofing material soft tiles, ondulin, corrugated board, metal tile or euroslate. There are two types of pitched roofs:

Ventilated. The design of the ventilated roof is suitable for equipping terraces and open-type gazebos used in the summer. The slope of the slope of such a roof varies between 3-6 degrees. The device of a shed roof of a ventilated type does not imply insulation, and sometimes even sheathing of the pediment.
Non-ventilated. The slope of a roof with one slope of a non-ventilated type is 2-25 degrees, depending on the type of roofing material used. This option is used to cover premises operated all-season, residential buildings, heated garages. Non-ventilated roofs are carefully insulated and sealed to reduce heat loss.

The peculiarity of shed types of roofs is that one gentle slope does not provide an independent descent of snow masses in winter, especially if roofing material with a rough structure was used in construction. Therefore, it is possible that in especially snowy winters, the homeowner will have to take up a shovel.

Strengths of a shed roof

Increasingly, designers and developers are abandoning complex projects in favor of buildings with a pitched roof. This is easily explained by its advantages:

Low cost. Thanks to the savings in building materials, the installation of a shed roof is 2-2.5 times cheaper than a gable roof of this size.
Simplicity. The design with one slope is quite simple for self-assembly. Even with little experience in construction, a novice craftsman alone will cope with the work, having a drawing and the necessary tools.
High resistance to gusty winds. A shed roof is the safest option if the construction site is located in an area with a constant wind rose, the main thing is to correctly determine the windward side and orient the slope along it.
Reducing heating costs. Since between the slope and ceiling at a distance less than that of other types, heated rooms are not cooled, which means that heat loss during heating of the house becomes less.
Availability of projects. Even if you are not able to make a drawing yourself, there are a huge number of ready-made, calculated projects with detailed diagrams truss system and nodes.
Ease of maintenance. The design of a shed roof allows you to assess the condition of the truss system at any time, replace damaged parts, strengthen the roofing material on your own, without the involvement of hired roofers, whose services are not cheap.

Types of truss system

The system of roof truss elements is a frame that bears and distributes the weight of the roof along the perimeter of the load-bearing walls, giving stability to the structure. Depending on the placement of the supports, two types of rafters are distinguished:

The basis for the construction of a hanging or layered truss system - detailed drawing, reflecting the exact dimensions and relative position of the elements and the method of attaching the main nodes.

The composition of the truss system

The shed roof scheme for a structure with a width of up to 4.5 m of a layered type includes a limited number of elements. The basis for the rafter system is a Mauerlat, made of a durable timber 150x150 mm.

It is fixed to the upper trim of the building along the walls on which the slopes are mounted. To form a roof slope, the walls are erected at different heights. The roof also requires rafter legs, which are made from boards measuring 50x150 mm.

From both ends of the board, cuts are made for Mauerlat. The legs are installed on a Mauerlat bar, inserting it into the cuts, fixing it with metal corners.

In order to evenly distribute the weight of the roofing material on all rafter legs, the installation of the crate is required. For soft types of roofs that are not able to keep their shape on their own, a solid type of crate made of moisture-resistant plywood sheets is used.

If corrugated board or tiles are used, it is enough to pin 25x50 mm slats across the rafters in increments of 20-13 cm. A puff, struts, a rack and a headstock are included in the complicated truss system of a shed roof.

All elements are made of first grade wood, dried to an optimum moisture content of 15-18%, sanded and processed antiseptic impregnation deep penetration.

It is important to strike a balance between the complexity of the truss system and the cross section of its elements - by complicating the design, you increase its weight. The recommended size of the rafters is calculated based on the temporary and permanent loads acting on the roof or determined from tables of ready-made values, taking into account the length and step between the legs, the type of wood.

Calculation of slope angle

The shed roof is good because, if it is correctly oriented according to the wind rose and the optimal slope is chosen, it will withstand a strong squally wind that would destroy the gable roof. To choose the angle of inclination of the slopes, you need to take into account 2 parameters:

A mounting roof is a great option if you want to quickly and inexpensively cover outbuildings or add a shed to your home. In addition, this is an excellent opportunity to hone your building skills without risking ruining the roof due to poor quality work.

Video instruction

If in the process of building a house you are thinking about how to properly and interestingly make a roof, then you have two common options - this is a shed and gable roof. Although gable roof is very popular, it is quite complex and it will take a lot of time to build it. Shed roofing is becoming more and more popular due to unusual look and ease of installation.

Therefore, in this article we will consider the construction of a shed roof, how to choose the right materials for the roof, how to insulate this part, and how to do the work yourself. And in order for the shed roof to turn out right with our own hands, we will provide drawings and photos.

Choosing the right angle of inclination of the roof

Shed roofs are quite simple, they are easy to build, but, most importantly, think through everything in advance. The angle of inclination of the roof can be determined depending on the snow, wind load and climatic conditions your area. In addition, it is important to consider that each material for sheathing a shed roof has its own minimum recommended angle of inclination. Let's consider some of them:

Slate and ondulin - at least 6 degrees.
Ceramic or cement-sand tiles- at least 10 degrees.
Bituminous tiles - at least 12 degrees.
Metal tile - at least 6 degrees.
Asbestos-cement slabs - at least 27 degrees.
Copper, galvanized or zinc-titanium sheets - minimum 17 degrees.
Decking - at least 6 degrees.

In the event that the minimum angle of the roof is more than the recommended one, there will be no problems; if it is less, it is necessary to redo it in order to obtain the recommended values. When you do not adhere to the technology of installing the roof and roofing material, it can not only start to flow at the joints, but also simply deform when a large amount of snow falls. Most optimal angle roof slope - about 20 °. But before starting work, it is better to calculate the angle that will suit your area. Also, please check when purchasing. this information consultants, as manufacturers sometimes indicate other figures for the slope of the roof. It happens that manufacturers can indicate a slope of 14 °, although GOST according to the minimum angle of inclination of this material is about 6 °.

Advice! If the roof slope is less than 12°, all joints of the roofing material should be greased. special composition, which will not allow the flow of a pitched roof. To do this, you can use bituminous mastic or roofing sealant.

It is very important to draw up drawings, thanks to which it will be possible to choose the angle of inclination of the roof and make correct calculations. If you are building new house or an agricultural building on which you plan to install a pitched roof, then one of the walls must be raised higher. For the correct calculation, you can use the right-angled triangle formulas. Please note that the calculation does not take into account the length of the roof overhangs. They are needed to protect the walls of the building from snow and rain. Minimum size the overhang should be at least 20 cm. In any case, it should not stand out against the general background and look harmonious with the roof.

Advice! There are many design programs with which you can see your idea in 3D. These programs will help you decide which overhang roofing suitable better and clearly show your house on the monitor.

Do-it-yourself shed roof step by step

Installation of the truss system

The shed roof device begins with the assembly of the truss system. This is the main frame of the roof, on which the roofing material will be installed. For work you will need:

timber 100 × 100 mm or 150 × 150 mm;
nails;
laying boards, at least 50 mm thick;
heat-insulating and waterproofing materials;
tape measure, stapler, building level;
chisel, ax, roofing hammer;
saw, knife, screwdriver.

The choice of rafter system for the roof depends entirely on the size of the building and the roofing material. Also, consider what the walls are made of. Mauerlat always serves as supports for rafters.

Roofing Mauerlat

Mauerlat is a beam laid on top around the entire perimeter of the wall. It plays the role of the lower support for the rafters. If a metal rafter frame is used for your building, then the Mauerlat is made from a channel or other metal material. This element connects the roof to the walls and distributes the load over their entire area. When installing a roofing mauerlat, it is imperative to lay a waterproof material (waterproofing) under the bottom. Often roofing material is used for this, which is laid in several layers. If this is not done, the wood will begin to rot, and the metal will rust over time. It is important to connect each link with two neighboring ones, which, together with the rafters, will turn into a fairly reliable structure.

In order to understand how to make a shed roof, it is important to take into account what kind of building you are covering. For example, if it is a shed, a utility block or a garage, then such a building does not require too large beams. If the width of the building reaches up to 6 meters, use pitched roof profitable. The thing is that the design is quite simple and does not require the use of supports or runs. This way you can save your energy, time and money. If the building is up to 5.5 m, beams from 50 to 150 mm can be used. If up to 4 meters - from 50 to 100 mm. But in any case, consider the weather conditions in your particular area. In addition, if the angle of inclination of the roof is small, it is not worth saving on beams. Indeed, otherwise, due to snow, the roof can simply bend and deform.

For the construction of a shed roof up to 4.5 m, the frame between the walls is quite simple. It consists of two Mauerlat logs, which are fixed on the walls, and rafter beams, based on the Mauerlat.

For the construction of a shed roof up to 6 m, between the walls you additionally need a bed and a rafter leg resting against the beam in the middle.

For the construction of a shed roof from 6 m, it would be good if there was another load-bearing wall inside, on which the racks could be supported.

For a shed roof structure larger than 12 m, the truss structure will be much more difficult due to the presence of additional rafter legs. If it is required to grow beams on the sides, for this you need to use wood of the same section. For reliability, it is important to fix two wooden plates on the sides, the length of which is at least 60 cm.

In order to attach the rafter beam to the Mauerlat, it is necessary to make a cutout in the rafter, with which it rests against the Mauerlat. If you do not want to bother with each rafter, create a template by which you will make the necessary cut in all the bars.

Advice! If you are making a roof frame on a wooden house, then the rafters cannot be rigidly attached to the Mauerlat. This is due to the fact that most of these buildings are sagging. Subsequently, the structure may warp. Therefore, for such buildings, fasteners are used, which are popularly called "slippery". They are corners that are attached to the Mauerlat and movably connected metal strips attached to the rafters. "Sliders" are fixed two per rafter leg.

Rafter installation

The installation of the rafters is as follows: we fasten the rafter beams to the Mauerlat. The intermediate distance should be determined depending on the selected roofing material. Usually it is from 50 to 80 cm. For fastening, you will need anchors or large nails. You need to lay the rafter end up or, in other words, “on the edge”.

It is important to carefully monitor the angle of inclination of each rafter board. If you let it out of attention, it will be difficult to put it out later. flat surface for laying roofing material. To simplify your work, install the first and last beam and pull the fishing line. This will serve as a guide and greatly simplify your work.

Advice! If all the walls of the building are even, and you do not want to cock one of the walls higher, then there is a way out. roof trusses save you both money and energy. Farms can be bought ready-made or do it yourself. For a garage or barn, wood is suitable as a material. For living quarters it is better to use metal.

The choice of roofing material

When choosing a roofing material, it is important to consider the type of building. For example, if this is a barn-type building, then you can choose not too expensive roofing material. If this is a residential building, then you need to choose a durable, aesthetically beautiful roofing material that will have good sound insulation. Below are the most common roofing materials:

All that is required of you is to weigh the pros and cons, decide on a budget and choose the right material for yourself. After that, you can start the device of a pitched roof.

Lathing installation

It is very important to level the base under the roofing material as best as possible. Otherwise, the roof will be uneven and even drips are possible. In addition, when installing roofing, it is important to adhere to the technology recommended by the manufacturer.

Roof insulation

For residential premises, the roof is better to be insulated. The warming process is carried out in the following order:

We fix the waterproofing with a stapler.
We install a heater.
We fill the counter-lattice.
Installing a vapor barrier.

The most common insulation material is mineral wool or polystyrene. Usually, 10 cm of a layer is enough for a roof, but information should be clarified for each region. Below is a diagram of the correct insulation.

Conclusion

As we have seen from this article, a shed roof shape is perfect for a garage or barn, as well as for the roof of private houses. Do not forget to inspect the already made surface for damage. In addition, timely repairs are important, and with the right material and technology, an excellent result is guaranteed to you!

In Russia, where there is a strong attachment to the traditional triangular-roofed tower, a shed roof is considered unrepresentative and unsuitable for a residential building. But for the construction of outbuildings and outbuildings, there is no easier and more economical option. Therefore, if you are planning to build a garage, a bathhouse, a barn, a shed, be sure to study the structure of the shed roof truss system in order to mount it yourself, without the involvement of hired workers.

Design features

The roof truss system of a single-pitched type is a simplified half of a double-pitched roof. Its advantages:

Light weight. The low weight of the structure allows you to build from scratch or reconstruct the roof without making changes to the foundation, without reinforcing it. This is a big plus, since the cost of building a foundation, even with your own hands, is about a third of the cost of the entire building as a whole.
Availability of materials. Since the truss system consists mainly of wood, inexpensive material, which is harvested and sold everywhere in central Russia, so the distance from the store to the construction site is minimal. The price of construction is acceptable for any budget.
Ease of installation. Typically, the salary of professional roofers is 50% of the cost of building a roof. Therefore, such a design with an elementary truss system makes it possible to minimize costs by refusing to hire third-party workers, and to fix the rafters of a shed roof with your own hands.

Despite the obvious advantages, it is impossible not to mention the disadvantages of this type of roof:

Low level of energy efficiency. Due to the fact that the air gap of a shed roof, which serves as a natural thermal insulating layer, is less than the same distance for a gable roof, it is not enough to prevent heat from escaping. The roof is made of materials with high thermal conductivity, so in summer it heats up a lot, in winter it cools down, transferring heat or cold to the under-roof rooms. To eliminate this shortcoming with your own hands, you have to organize more thorough insulation and ventilation of the premises.
The inability to equip the attic. For some homeowners, an attic is necessary, but it is problematic to equip it under a pitched roof. But on the surface of a slope with a slight slope it is convenient to place solar panels, water heating tanks and even a small area for relaxing and sunbathing.
Formation of drifts and snow drifts. This problem is relevant for outbuildings adjacent to the main residential building. Snow slides off the steeper slopes of the roof of the house and lingers on the more gentle garage. However, if you make the calculations correctly, choose the right material, this drawback will not bother the owners.

Construction of the truss system

The rafter system of a shed roof is nothing complicated, especially for those who are familiar with the device of a gable roof. It consists of the same basic support elements that the diagram shows:

Mauerlat. Strong, massive base, made of timber with a section of 150x150 mm. Mauerlat is attached to the top of the walls so that it takes on the weight of the roof and redirects it to the foundation. It is not installed only in houses made of logs and timber, in which Mauerlat performs the tasks upper crowns log house. In structures made of brick or gas silicate, formwork is established along the upper edge of the wall and a concrete screed is poured.
Rafter legs. The rafters are smooth, durable bars made of wood with a section of 50x150 mm or 100x150 mm. They rest on the walls, forming the geometry of the slopes. The step between the two rafter legs is chosen between 60-120 cm. It should be borne in mind that both too rare and too frequent a step is undesirable: if there are unreasonably many rafters, the structure will turn out to be too heavy, if not enough, it will not withstand the weight of the roofing material. The distance between rafters determine the engineering calculation.
Strut. Also called a rafter leg, an element of additional support. It departs the racks at an angle, supporting the middle part of the rafters, preventing its deflection. Struts are also made of wood, boards with a section of 50x150 mm.
Rack. A vertical support, which stands on one side of the load-bearing partition, and on the other supports the rafter leg, transferring its weight to the foundation of the building. The step between the uprights should be 1.2-1.5 m, a larger distance does not provide proper support.
Sill. They are made from the same material as the Mauerlat, it performs the same functions, with the only difference being that it is installed on the internal supporting walls.
Fight. A horizontally located board that pulls together two racks, preventing them from bursting.
Filly. They are used if the length of the rafter legs is not enough for the construction of a roof overhang. These are boards of a smaller section, with the help of which the rafters are lengthened. The distance from the stand to the end of the filly must be at least 40 cm.

Types of truss systems

Depending on the layout of the structure, for the installation of a pitched roof, different kinds truss system that best meets the specified conditions:

Design Options

To understand what elements the truss system of your shed roof should have, what should be the step between them, you need to measure the length and width of the building, determine the distance between bearing walls. If the structure's length is:

4.5 meters or less. If the distance between the partitions is small, you can choose the simplest option, consisting of a firmly fixed Mauerlat and rafter legs. Installation does not cause significant difficulties, can be done by hand. This method is used for outbuildings of a small area: garages, sheds, outdoor toilets.
4.5-6 m. If the distance exceeds the recommended values, six-meter rafters that are not supported by internal partition will sag under their own weight. Therefore, the rafter system must be reinforced with struts resting on a bed mounted on a floor beam.
Up to 12 m. If the length of the roof exceeds 12 meters, at least one rack is mounted on which the struts are supported. The step between the rafters and the uprights should not exceed 1.2-1.5 m.
Up to 16 m. For structures, the distance between the walls of which exceeds 16 m, it is required to install at least two racks fastened with a scrum, multidirectional struts. Such a truss system is used extremely rarely, it is suitable for arranging large sheds for keeping livestock or warehouses.

You need to understand that the larger the building, the more complex the truss system it requires, the smaller the step between the rafters. Because standard length lumber is 6 meters, then structures whose width exceeds 4.5 require the manufacture of composite rafter legs, consisting of one or two boards connected with an overlap of 50 cm.

Drafting a project

So a shed roof has the shape of a triangle, some of the side lengths of which we know, you can calculate the rest using trigonometric formulas known to everyone from school. Let's assume that the hypotenuse is a rafter leg, let's denote it Lc. Then the segment Lbc is the leg, the height of the wall from the floor beams to the ridge. This means that Lcd is the width of the house, A is the angle of inclination of the slope (selected or calculated). Now it all depends on which sides we know:

If the width of the house and the height of the wall from the ceiling to the ridge are given, then we calculate the angle of inclination using the calculator: tgA=Lbc/Lcd;
If the slope angle and the width of the structure are known, then we calculate the height of the wall: Lbc=tgA*Lcd;
When the width of the building and the angle of inclination of the slopes are determined, the length of the rafter leg can be calculated: Lc = Lcd / cosA.

After the calculations are completed, a diagram is drawn on which the resulting dimensions are applied. The simplified drawing also reflects the step between the rafter legs.

Assembling the truss system

Since the sequence of work depends on the type of truss system, we will analyze how to build a shed roof for a garage with a width of 4.5 m with our own hands. Since the dimensions of the building allow, you can get by with the construction of the simple type shed roof truss system: