Do-it-yourself hipped roof. Rafting system of a hipped roof: the main features of the frame Roof plan of a hipped roof

The final structural element of the building should not only reliably protect from precipitation, keep warm, but also emphasize the architectural merits. The shape is classified by: angle of inclination (flat, pitched); the presence of arches, domes; the number of outer and inner ribs; the number of planes (slopes). The more complex the system, the more likely it is that a construction crew will have to be hired to complete the work. It is necessary to choose not the easiest option, but interesting from the point of view of design. A hipped roof is the perfect solution.

Execution types:

• Hip - consists of two triangular slopes, abutting tops at the end of the ridge. The other two planes are trapeziums.
• Half-hip - differs from the first version in that part of the inclined surface is occupied by the pediment. The roof has a shortened appearance along one or two planes. It experiences less wind and snow loads. Another plus is the ability to install full-fledged windows or balconies in the gable area in the attic.
• Hip - triangular slopes converge at one point. The use of such a solution is advisable for a house with the same dimensions of the outer walls.

Features of hipped roofs:

• More even distribution of the load on the foundation, along the entire perimeter.
• Reducing the volume of the attic space - reducing heat consumption for heating, the complexity of organizing the attic space.
• Good resistance to wind and snow loads.
• Higher structural rigidity due to the increase in the number of external ribs.

The nuances of the hipped roof:

1. At the ends of the ridge beam, the central intermediate and diagonal rafters converge. The organization of the node is quite complex.
2. The corner rafters are attached to the corner.
3. It is necessary to maintain the angle of inclination of the elements to create a plane for the installation of the roof.
4. The slope of the corner rafter is always less than that of the central and intermediate ones. This is the longest element.
5. It is supported by a Mauerlat and a ridge girder.

Instructions for the selection and calculation of the rafter system

The construction of a house begins with the design of the project. Self-development of a drawing is impossible without:

• studying construction technology;
• calculation of farms.

Factors influencing the choice:

• the angle of inclination of the slopes;
• hip roof material;
• the weight of the "roofing cake";
• wind and snow loads;
• seismic hazard;
• overall dimensions of the house box, the presence of internal load-bearing partitions, columns;
• planning the organization of the attic space.

The slope of the slopes is determined not only for aesthetic reasons. It is important to find a middle ground between a positive visual perception and maintaining the reliability and functionality of the structure. The angle is closely related to almost all of the above factors:

• The use of all types of roofing materials is limited by the range of this parameter.
• The smaller the angle of inclination, the less the effect of the wind load.
• An increase up to 45-60 ° guarantees independent precipitation. The impact of snow cover is minimized.
• By reducing the angle of inclination, we obtain a reduction in the area and weight of the entire system. The consumption of thermal energy for warming up the attic space decreases.
• The organization of the attic floor is unlikely with a small slope.

Types of roof trusses

1. Slanted - the structure of the hip roof is based on:

• external walls (mauerlat);
• run (ridge);
• on internal load-bearing partitions, columns inside the house through the bed.

The distribution of the load occurs due to the installation of additional racks under the ridge beam. Lezhen shares pressure across the entire surface of the inner partition (column).

2. Hanging - applicable for structures with a maximum foundation size of 6 ~ 7 meters. The rafters are supported by the walls. Load distribution by means of struts, tightening, crossbars, struts. For hip roofs, this type is rarely used.

Instructions for calculating the rafter system

Drawing a hipped roof is impossible without performing mathematical calculations.

1. The size of the run - is determined based on the dimensions of the house. Standard solution: length minus width. The middle of the ridge bar is located clearly above the intersection of the base diagonals. The purlin line is parallel to the front walls.

2. Ridge height: H = b x tgα. b - half the length of the end walls of the house, α - slope of the slopes. The numerical value of the tangent is determined from the Bradis table.

3. The size of the central and intermediate rafters of the ramp: Lctr.slide = √ (H² + b²).

4. The length of the central rafter leg of the hip: Lctr.str. Hips = √ (H² + b²). With a non-standard choice of the size of the ridge, the value of b is determined as half the difference between the lengths of the house and the run.

5. The size of the diagonal elements: Ldgn.p. = √ (Ltr.str. Hip² + b²).

6. Calculation of the lengths of the wristbands - the property of similar triangles is used. If the angles are equal, the proportion of the lengths is fulfilled on one of the sides, then the ratio of the rest of the components of the figure will be observed: D = 3/4 C, which means: Lnap = Ltr.st. hip x 3/4.

7. The distance between the rafters depends on the choice:

• Section sizes, wood quality. The weaker the material, the smaller the step should be.
• The presence, type of heat-insulating layer - is determined by the ease of installation of insulation (60-120 cm).
• Roofing material, its weight and geometry. The greater the total mass, the smaller the step. As with thermal insulation, the dimensions of the sheet are taken into account.

The minimum step between the trusses is 60 cm, the maximum is 2 meters.

8. Formation and calculation of overhangs depend on the preferences of the tenants and the height of the house. The minimum size for a 1-storey building is 500 mm. The task is to protect the walls from precipitation.

Construction of a hip rafter system

Mauerlat - timber or upper crown, strapping of the house, to which the rafters are attached. Provides even distribution of the load on external walls. Section: 10x10 cm ~ 15 * 15 cm. Armopoyas is a reinforced concrete structure along the upper perimeter of the walls. Its task is to strengthen the base under the Mauerlat, to ensure reliable adhesion to the roof.

Mauerlat installation options:

• On a reinforced concrete belt using embedded studs, anchors.
• Anchors into the body of the wall are brick one-story houses with a slight slope of the hip roof.
• On the last crown of a wooden frame or the upper strapping of a frame structure.
• Installation on studs embedded in brickwork.
• With staples hammered into wooden inserts inside the brick wall and the body of the Mauerlat.
• Wire made of non-heated steel, laid at the time of the construction of the facade.
• On studs fixed in the wall with a chemical anchor - a two-component composition. The glue is introduced into the drilled holes in the masonry of the house, dries and holds the element securely.

Peculiarities:

• The number of studs, brackets, anchors must be greater than or equal to the number of rafter legs.
• Roofing material is laid under the timber or bituminous mastic is applied to the base.

Installation Guide:

• The marking of holes for studs, anchors is carried out by laying the rails on the fasteners, followed by a blow to the surface of the tree. Drilling is performed along the notches. The beam is put on pins, fixed with a washer and a nut.
• Wire connection - the ends are passed over the strips, twisted.
• Extension schemes for long sections:

• The floor beams are laid either on the same level with the Mauerlat, or on a bar fixed to the wall. Step - 0.6-1 meter.
• Mauerlat screed with rails, to which the racks for the girder will be fixed in the future.
• After completion, on the surface of the Mauerlat, the rafters are laid out.

Installation of purlins

The ridge bar experiences significant loads and is installed on the racks. Depends on the correctness of the work:

• Symmetry of the structure, uniformity of weight distribution.
• Reliability of a four-pitched roof at maximum wind and snow loads.

Brief installation instructions:

• The scheme (hanging, hinged) depends on the presence of internal load-bearing partitions. The racks can be fastened to screeds or ceilings.
• In large houses, the structure must be reinforced with struts to resist stress.
• The material for the ridge and supports is chosen of the same section, not less than 100x100 mm.
• Before work, carefully measure and determine the central and extreme points of fixing the racks. Their number is affected by the length of the run. Step - no more than 1 meter.

Installing rafters with your own hands

There are two work orders:

• First the central rafters, then the diagonal ones. Narodniks are installed last.
• Installation of diagonal elements, then - central ones.

The first method is considered to be simpler. The second allows at the initial stage of work to control the symmetry.

Mounting options for the Mauerlat:

• Rigid - in the rafters, a saw is performed, the depth of which is no more than 1/3 of the width of the bar. The recesses (saddle) can be cut from the template.
• Sliding - used for structures that shrink. For fixing to the Mauerlat, special fasteners are used, floating supports for the rafters. With this method, the connection of the legs above the skate is performed in a hinged manner.
• Reinforced - the end of the rafter rests on the Mauerlat. The overhangs of the hip roof are formed by extending the legs with additional slats (fillets) of a smaller section. This method saves material costs.

Decoration of the ridge knot of the central, intermediate opposite rafters:

• Butt - connection with cutting the ends of the legs at an angle. Cross-sections are conjugated. The assembly is fastened with nails. Additional fixation will be provided by a metal plate or wooden plate.
• Overlap - the rafters overlap each other with side surfaces. Fastening - hinged (bolt), nails.
• To the ridge bar - joining the rafter section with the side surface of the girder.

Features of mounting diagonal legs:

• Placement of the upper unit with an emphasis on the cut of the slant rafter in the lateral surface of the central elements of the system.
• To strengthen the diagonal legs that are experiencing the greatest load, the installation of truss trusses and racks is required.

The installation of the rafters to the diagonal rafter is carried out by sawing and docking with its lateral surface, fixing with nails.

At the end of the work, it is necessary to check the equality of the angles of inclination and the lengths of the opposite rafters, compliance with the plane of the slopes and hips.

Nuances and possible mistakes

1. When purchasing lumber, you need to make sure that:

• The moisture content of the tree does not exceed 20%. When dry, the board changes geometry, which will lead to a change in length, straightness. Violation of proportions entails leakage, a decrease in resistance to wind and snow loads. The best quality is obtained from wood harvested in winter in regions with cold climates. Before making a purchase, ask your dealer for a moisture measurement.
• In the body there are no cracks, ingrown knots, traces of the vital activity of insects.
• When purchasing glued laminated timber, make sure of the decency of the seller, manufacturer. The use of low-quality products will lead to a violation of strength.

2. Elements of the truss system can be ordered from factories specializing in construction and turnkey house manufacturing.

3. Wood is treated with antiseptics and fire retardants before starting installation work.

4. The length of the purchased rail sometimes does not correspond to the calculated size. Extension technology:

• Oblique notch with maximum fit of the mating planes. A bolt or hairpin is inserted into the through hole with an interference fit, without backlash; tighten the nut.

• An overlap of more than 100 cm is carried out with the help of nails, bolts, studs in a checkerboard pattern.

• Cross-sectional joint - sawed off at 90 °. The docking place on opposite sides is covered with overlays. Fastening - as in the previous method.

5. The nodes are additionally fixed with metal fasteners: corners, plates and others. Each of these elements has holes for hardware. It is advisable to use products with oval slots that allow slight displacement of the mating surfaces. In the process of shrinkage, exposure to loads, rupture of the rigid connection may occur.

• Lack of calculation of loads, weight. Exceeding the permissible indicators entails the destruction of the foundation, roof frame. The necessary calculations can be performed independently or by using online calculators. Engaging specialists is the best solution.
• The step is greater than the calculated value. Having saved on materials, the master will acquire many problems.
• Control of the plane of the slopes and hips with a cord is not performed. Deviations will cause the roof to sag, violate the tightness and reliability of the roof, up to its deformation.

Presentable appearance, reliability, durability - all this is a hipped roof, the drawing, calculation and installation of which, of course, is quite difficult to do on your own, but you can always turn to qualified specialists for help.

A noticeable advantage of hipped roofs is that in such buildings it is very convenient to equip attic floors. The premises are very comfortable and spacious, ideal for living in contrast to houses, for example, with gable roofs.

Currently, more and more buildings began to appear, made according to this plan. The advantage of a multi-slope roof is the possibility of using it on completely different buildings, from a bathhouse to a large private cottage.

Houses with hipped roofs look really solid and expensive, and therefore, you should not spare the time and money for its arrangement.

The main types of hipped roofs

There are no pediments (these are triangular ends of the facades of the building, bounded on the sides by two roof slopes, and at the base by a cornice) on such a roof, and the attic windows are placed in the slopes.

This roof is much more economical than the gable roof in terms of the cost of wall building materials, but the inclined ribs at the joints of the hips and frontal slopes require the installation of a very complex rafter structure and additional measurement and adjustment of the roofing material.

Slopes are often made with different levels of inclination, due to which the silhouette of a sloping roof is created.

• Half-hip (Danish) design. It differs from the previous one by the presence of a pediment, which has a small hip at the top. Protection against wind loads at such a roof is provided by a ridge (the upper horizontal edge of the roof formed due to the intersection of two slopes). Most often, such a roofing device is found in regions with frequent strong winds.

• Hip design. It looks like a pyramid: four triangular slopes, converging tops in one place. Such roofs do not have gables; they are erected on small buildings in the form of an equilateral polygon or square. Installation of a rafter system at such a roof is very difficult.

Creating a hipped roof project

Before starting work on the arrangement of the roof, it is necessary to design it, carry out calculations for the structure, and also create its drawing.

The project of a hipped roof provides that the slope of the slopes of such a roof can be in the range from 5 to 60 degrees. It depends on atmospheric loads, the purpose of the attic and the type of roofing materials used.

In areas with frequent and heavy precipitation, the slope of the slopes should be significant (from 45 to 60 degrees). In regions with strong winds and rare rainfall, the slope of the slopes is usually much less.

If the angle of inclination is approximately 5-18 degrees, the use of a roll cover is recommended; 14-60 - asbestos-cement sheets, roofing metal; 30-60 - roof tiles.

The height of the roof ridge is calculated using a trigonometric expression for right-angled triangles.

Calculation of rafters - the beginning of drawing up the entire project of the house. Their cross section is determined depending on the expected load (weight of roof structures, roof pie, external influences), and the degree of roof slope. With the help of calculations, the step between the rafters is also determined, their bearing capacity is checked.

The plan of the rafters of the hipped roof provides for which rafters it is advisable to use - layered or hanging. It also turns out if additional elements are needed: braces, tightening, etc.

If it happens that the standard parameters of lumber are not suitable for the future roof, you can modify them. For example, you can lengthen the rafters or double the beams. You can also use glued or inlaid rafter legs (they are noticeably more powerful and longer than usual).

Impact of loads on the rafter system

The rafters are subjected to constant (the mass of the roof, battens, rafters, etc.) and temporary (wind, precipitation) loads. The main calculated parameter of the snow load, adopted in Russia for the middle lane, is 180 kg / m2. A snow bag can increase this figure to 400-450 kg / m2.

If the roof slope is greater than 60 degrees, the snow load is not taken into account.

The standard design value of the wind load for central Russia is 35kg / m2.

If the roof slope is less than 30 degrees, the wind correction is not taken into account in the drawing.

The load parameters are adjusted for local climate conditions using special factors. The total mass of the roof is calculated based on the amount of materials used and the total area of ​​the structure.

The calculations include indicators of the payload on the system, if ceilings are suspended from the farms, water heating tanks, ventilation chambers, etc. are installed.

It is mandatory to calculate the strength of the rafters and the degree of possible deformation under various conditions.

Most often used as rafters: a rectangular beam with a section corresponding to the calculated loads, boards with parameters 5 × 15, 5 × 20 cm.

Most often, the choice is made on coniferous sawn timber (spruce, pine) with a moisture content in the range of 18-22%, treated with antiseptics and fire retardants.

To increase the rigidity and stability of the geometry of the rafter system of the pitched roof, steel elements are sometimes introduced.

Installation and installation of the rafter system

Before proceeding with the installation, you need to select the necessary materials and tools. In addition, it would be nice to get a drawing of the entire structure on paper. Of the materials you will definitely need: thermal insulation (mineral wool, for example), waterproofing, vapor barrier, wooden beams, roofing material, wood for the lathing. Required tools: drill, screwdriver, hammer, nails, screws, level, tape measure, measuring stick, etc.

The scheme of a four-pitched roof assumes the presence of rafters, support beams, braces, and other elements necessary to impart rigidity to the entire structure.

Rafters with a cross section of 5 × 15 cm will add reliability to the structure. When shopping for lumber for rafters, do not choose wet, twisted, or severely flawed.

The roof is always installed from the bottom up. The first step is to lay the support beams (Mauerlat), on which the rafters are subsequently installed. So you get a lower frame, which should extend beyond the walls by 40-50 cm. It is not desirable that the bulging of the rafters from the edges of the walls exceeds the limits specified above, otherwise the object will look inharmonious.

Do not forget to check the correct installation with a building level.

If the building has wooden walls, support beams are not needed, since the upper crown of the frame will act as a Mauerlat.

After that, frame rafter legs are installed from each corner of the building, they are called diagonal legs. The upper parts of the rafter legs, if necessary, can be supported by a system of braces and struts. Their main task is to unload the rafters by redistributing the load along the inner walls or support pillars, and also to give the entire structure sufficient rigidity.

You should be very careful about the nodes for attaching the rafter legs to the Mauerlat. These are the main points that are responsible for the strength of the rafter system as a whole. The overhang of the hipped roof is adjustable by the length of the diagonal rafters.

A special table of coefficients with the ratios of length and laying of rafters for different slopes of the roof slope will help in the work. In one column, the coefficients for the intermediate ones are indicated, in the other - for the corner rafter legs.In order to calculate the required rafter length, multiply the laying by the coefficient. You can easily find such a table on the Internet.

In places where there are no load-bearing walls, the heels of the rafters can be placed on the longitudinal beams (side girders). In addition, a beam is mounted in the center, it is mounted on three supports: in the middle and at both ends.

If you have a large roof area, you cannot do without arranging truss trusses, which will take on part of the load from the rafters. Truss trusses need a tightening device on which they will be supported. Sometimes they can be attached to existing transverse or longitudinal beams.

The parameters associated with the height and degree of the roof slope are determined precisely by the height of the slanting rafters and the horizontal upper beam (ridge run).

After you have installed the rafter guides, proceed with the construction of the main frame. Fasten the inclined (rafter) rafters to the support beams, as well as to the ridge girder.

They should be installed in increments of 40-50 cm, no more. If the gaps are too large, the rafter system may not withstand the loads from the snow that has fallen. The diagram of the rafter system of a hipped roof must take this fact into account.

Fasten the inclined rafters together at a distance of about a meter from the upper rafter beam using boards with a cross section of at least 4 * 12 cm.

It is not necessary to select rafters strictly in length, because they will most likely have to be cut. The main thing is to make sure that they are not too short.

• in order to reduce the likelihood of errors to a minimum, use not a tape measure for measurements, but a special measuring rod;
• mark the centerline along the top trim of the end wall. After that, measure half the thickness of the ridge bar, draw a line for the placement of the first of all central intermediate rafters;
• Align the end of the rail with the line for the placement of the rafter that you marked a little earlier. On the other end of the measuring rod, copy the line of the inner contour of the side wall (thereby you will lay the intermediate rafter). Transfer the line of the outer contour of the wall and the overhang of the roof to the measured rail;
• to determine the future location of the second of the central rafters, move the measuring rail to the side of the wall, transfer the desired position of the rafter to it from the inner corner of the upper strapping;
• repeat the entire algorithm of actions in each of the corners. By adhering to this diagram, you will determine the location of the ends of the ridge bar, as well as all the center intermediate rafters.

After installing the rafter system in accordance with the plan, the crate, vapor barrier, waterproofing, counter-lattice, as well as roof insulation are made.

The final stage of the construction of a hipped roof

After the installation of the entire structure, a hipped roof (like any other) provides for the creation of a crate. For this purpose, wooden boards with a thickness of 50 or 40 mm are used. The main thing is that the material is of high quality and well dried.

Before the installation of the lathing, it is necessary to lay a film that insulates the roof from steam and moisture. This film is attached with a stapler. In addition, in no case should you lose sight of the thermal insulation, which should be equipped in the attic. Thermal insulation is necessary to maintain a normal temperature in the building. And after that, a four-pitched roof is installed.

And the last stage is the laying of the roofing. You are not limited in your choice, be guided by your own taste, material capabilities and design features of your roof. The main thing is to attach the material firmly enough, carefully so that rain cannot penetrate into the room through the joints, and the wind cannot tear off fragments of the roof.

The scheme of the rafter system of the hip roof is very complex, as mentioned above more than once, but you should not be afraid of it. The most important thing is to make all calculations and measurements correctly, and also not to be mistaken with the markup. Having thoroughly understood this once, you can easily repeat a similar construction. Of course, it will be quite difficult for one person to cope with the upcoming volume of work, so a couple of assistants will not hurt.

The roof is just as important as the foundation and walls. Its design sets the mood for the entire architectural ensemble, makes the building neat and attractive. The four-pitched roof has gained wide popularity not only because of its high reliability and external attractiveness, but also due to the opportunity to equip additional structures - dormer and dormer windows, bay windows, etc. Despite the fact that the installation of such a roof is a little more expensive and more complicated than a gable structure , it is still easy to build it with your own hands.

Advantages of gable roofs over gable structures

One of the main tasks that appears even at the stage of designing your own house is the choice of the type of roof. The presence of many options among gable and gable structures requires an answer to the question of which roof to give preference to. And although the aesthetics of the structure plays an important role, the criteria of reliability and practicality still come to the fore.

The gable roof is a classic structure, which is formed by two opposite slopes and a pair of vertical end parts, called gables. The spacious under-roof space allows you to equip the attic, living quarters or use the attic for domestic purposes.

The classic gable roof is easily recognizable by a pair of rectangular slopes that adjoin each other along the central axis of the building, and two triangular pediments at its ends.

Structures of this type, due to their simplicity and practicality, have remained the most popular in individual construction for a long time. At the same time, the dependence of the geometry of the roof on the size of the structure, as well as the complication and rise in the cost of the structure when arranging the attic, forced to search for other, more practical and functional options. And they were found in the form of a variety of hipped roofs, which basically have a pair of triangular and two trapezoidal slopes. The latter are often called hips, and the roof itself is called hip. When erecting a structure of this type, the need for pediments disappears and it becomes possible to make the building more modern and original.

There are several advantages of hip roofs over traditional gable structures:

• the possibility of arranging attic windows directly on the slopes;
• increased strength, reliability and stability of the rafter system;
• increased resistance to weather factors;
• the possibility of increasing the area of ​​the attic by simply reducing the width of the hip base;
• more even distribution of the weight of the roof;
• improved temperature regime when arranging an attic room.

Don't be fooled by the many advantages of a more stylish hipped roof - it also has disadvantages. These include a more complex design, a slight reduction in the size of the attic space and an uneconomical waste of roofing material. As for costs, the budget that will be required for the construction of both roofs does not differ significantly.

Hip roof classification

Differences in the shape of buildings, as well as the requirements for functionality and practicality of traditional hip roofing, have contributed to many variations. If you do not consider the most exotic of them, then there are several main types of hipped roofs.

1. Traditional hip roof, the side slopes of which reach the level of the cornice. For the construction of its main surfaces, straight rafters are used, and the ribs of the hips form bars extending from the ends of the ridge. The well-developed design and distribution of the weight of the roof over an increased area allows not only placing the overhangs on one line, but also increasing their overhang. Thanks to this, the facade of the building is reliably protected from rain, even with strong gusts of wind.

   
   Glazing elements are often built into the slopes of a classic hip roof

2. The hipped roof can be installed on a house that is square in plan. A feature of this design is the slopes of the same configuration. Their edges converge at one point, and their hips are in the form of isosceles triangles.

   
   Hip roofs are widely used in modern individual construction

3. Half-hip roofs got their name from the shortened hips. In contrast to the traditional roof, their length decreases 1.5–3 times in comparison with the dimensions of the main slopes.

   
   Side slopes of half-hip roofs have a shortened length, so they don't reach the cornice line

4. The Danish half-hip roof has a small gable under the ridge and a short hip on the eaves side. This design allows the installation of ventilation and lighting elements directly into the vertical end of the roof, thereby eliminating the need to install roof windows.

   
   The Danish project is good because it allows you to easily equip attic spaces

5. The semi-hip Dutch roof has a vertical pediment that divides the hip into two short ramps. The rafter system "Dutch", although it has increased complexity, but it allows you to make the attic more spacious and practical. In addition, this design is excellent for the installation of vertical glazing in the attic.

   
   The roof, built according to the Dutch project, is still rare in our area.

6. The sloping hipped roof has several slopes of different sizes on one slope. Thanks to their different slopes, it is possible to increase the volume of the roof space. Although the broken structure cannot be called simple, houses with such a roof are very common. The reason for the popularity is the ability to equip additional living rooms on the upper tier. For this reason, a roof with broken slopes is often called an attic.

   
   The sloping roof makes the architecture of the building somewhat heavier, but it allows you to equip several living quarters in the attic space

There are also more complex structures of many hips, as well as those in which a hipped roof is combined with other types of roofing systems. The design and installation of such a roof requires many years of experience and knowledge, therefore it is better to entrust the construction of a tricky roof to specialists.

Design of hipped roofs

When developing a hip roof, all types of loads that will act on it are taken into account. To do this, first of all, several important issues should be resolved:

• the purpose of the attic space;
• roofing material;
• the degree of atmospheric impact in the construction region.

Based on these factors, the degree of slope of the slopes and the area of ​​the roof are determined, the loads are calculated and a decision is made on the design and parameters of the rafter system.

Geometric parameters of the slopes

The angle of inclination of the slopes depends on the snow and wind load, therefore it varies over a very wide range - from 5 to 60 degrees. In areas with rainy weather and high snow cover, roofs are erected with a slope of 45 to 60 degrees. If the region is characterized by strong winds and minimal rainfall, then the slope can be reduced to the very minimum.

When determining the angular parameters of the roof, it is imperative to take into account what material it will be covered with:

• slate sheets, ondulin, roofing metal and roll materials are laid on slopes with a slope of 14 to 60 degrees;
• the tiles are mounted on a surface with a slope from 30 to 60 degrees;
• roll coating is used on sloping slopes - from 5 to 18 degrees.

Having decided on the angle of inclination of the roof, it is not at all difficult to calculate at what height the ridge will be. To do this, use simple trigonometric formulas for a right-angled triangle.

Roof area

Even the most complex hip roof consists of individual slopes that repeat the contours of the simplest geometric shapes, so most often for calculations it is enough to know the linear dimensions of the base and the angles of inclination of the hips.

The total roof area is calculated by summing the quadrature of the individual hips. Slopes of complex configuration are divided into several simple surfaces, after which separate calculations are carried out for each of them.

Calculation of loads

Loads acting on a hipped roof are divided into two types:

• permanent,
• periodic.

The first includes the weight of roofing materials, rafters, battens and other frame parts. The second is the effort that precipitation and wind force exert. In addition, the calculation should take into account the payload in the form of a variety of engineering systems and communications attached to the elements of the rafter system.

Focusing on SNiP, when designing a roof, it is necessary to take a snow load of 180 kg / sq. m. If there is a danger of snow accumulation on the roof, this parameter rises to 400-450 kg / sq. m. If the roof has a slope angle of more than 60 degrees, then the snow load can be ignored - on surfaces with such steep slopes, precipitation does not linger.

The force of wind loads is much less - up to 35 kg / sq. m. If the slope of the roof is from 5 to 30 degrees, then the effect of the wind can be neglected.

The above parameters of atmospheric effects are averaged values ​​adopted for the middle lane. When performing calculations, correction factors should be used depending on the region of construction.

Calculation of the rafter system

When calculating the rafter system, the pitch of the rafters and the maximum load that they can carry are determined. Based on these data, a decision is made on the installation of braces, which contribute to the redistribution of the load, and puffs, which protect the frame from loosening.

The presence of hips on hipped roofs, in addition to the usual rafters, also requires the installation of diagonal (in another way, oblique) - those that are attached to the ridge and directed to the corners of the building. Their length is greater than the transverse nodal elements of the roof. In addition, shortened elements are attached to the diagonal ribs. Compared to conventional rafters, the slant legs experience a 1.5–2 times greater load, so their cross-section is doubled, and to ensure multi-span, they are propped up with one or two racks.

Often, hip roofs have a complicated rafter system, which, in contrast to a simple four-slope structure, exerts an additional load in the places where vertical supports are installed. This feature must be taken into account when calculating the strength of the wooden roof frame.

The distance of laying the rafters is called a step and is determined based on the length of the rafter leg and the section of the lumber used. It is most convenient to determine this parameter using special tables, one of which is given below.

Table: dependence of the section and pitch of the rafters on their length

Manual calculations are quite time consuming. To reduce design time, you can use one of the online hip roof calculators. With its help, you can determine not only geometric parameters, but also a lot of other equally important factors:

• the amount of moisture and thermal insulation, taking into account overlaps;
• the amount of roofing material, including waste generated during cutting;
• the amount of lumber required to equip the rafter system;
• length of overhangs, etc.

Video: using a construction calculator to calculate the roof

What materials will be needed to assemble the rafter system

For the construction of a hip roof, a bar and a board made of larch, pine and other coniferous wood are best suited. When choosing a material for construction, it is necessary to carefully reject defective boards. Fungus damage, knots and cracks reduce the strength of the boards and affect the durability of the roof. When the moisture content of the wood is more than 22%, lumber is stacked in the open air and dried. It should be understood that unfinished boards can warp, and this, in turn, will lead to a violation of the geometry of the roof with possible damage to the finish coating.

To assemble a wooden frame, a rectangular bar with a section from 80x80 mm to 150x150 mm is used - the exact parameters are determined by calculation or using the table above. Alternatively, you can use a board with a section of 50x100 mm or 50x200 mm. If there is a need to strengthen the rafter leg, then use paired boards.

For reliable fastening, as well as increasing the rigidity of the wooden frame, steel brackets and other metal elements are used. Often, not wooden, but steel supports are installed under especially loaded ridge girders. Combined frames have increased strength and reliability.

Features of the rafter system

In order to properly design and install a hipped roof, it is necessary to understand in detail its structure, as well as the features of the arrangement of hip roofs of the most common types.

The device of the rafter system in detail

The hip roof frame consists of most of the same parts as the gable, but a more complex rafter system requires the installation of additional elements. Upon closer examination, you can find the following components:

All of these elements can be found in any type of hipped roof. The only exception is the hipped roof, which does not have side rafters and ridge beams.

In wooden and frame houses, the rafter system is mounted without a Mauerlat. In the first case, its functions are taken over by the extreme crowns, and in the second - by the upper strapping.

Varieties of rafter systems for hip roofs

Since the basis of the rafter system of the hip roof is made up of nipple rafters, the following rules must be adhered to when installing the roof frame:

1. In structures where the slant legs experience an increased load, a beam of double thickness is used for their manufacture.
2. The splicing of individual parts of the diagonal rafters is performed in places with a maximum load (most often in their upper part) and strengthened with struts and vertical racks installed at an angle of 90 ° to the rafter legs.
3. In the manufacture of overhead rafters, a margin should be provided for on-site trimming, therefore, the estimated length of the timber is increased by 5-10%.
4. The critical junctions of the rafter legs must be reinforced with metal fasteners - brackets, twists or perforated construction strips.

When choosing a rafter system, it is imperative to take into account the size of the building and the presence of internal supports or capital walls. Based on the specific conditions, choose a scheme with hanging or layered rafters.

Hanging rafter system

The roof structure with hanging rafters does not have support along the centerline, so the bulk of the weight falls on the walls of the outer perimeter. This feature manifests itself in the redistribution of internal forces - the rafter system is subjected to compressive and bending loads. As for the walls, significant bursting forces are transferred to them. To eliminate this factor, each pair of rafters is interconnected by so-called puffs - jumpers made of wooden beams or rolled metal.

The tightening can be located both at the base of the rafter legs, and above. In the first case, the lintel will also play the role of a transverse beam, which is a good option for the construction of an attic roof. If the tightening is installed in the midline area or higher, then it will only serve as a fixing link. It should be noted that the cost of the rafter system depends on such a seemingly insignificant moment as the installation height of the puffs. The higher the transverse jumpers are located, the larger the cross-section of all the components of the wooden frame should be.

Construction with layered rafters

A hip roof with layered rafters is only suitable for those houses whose interior space is divided into two equal parts by a main wall or supporting pillars installed to support the ceiling. In this case, the lower edge of the rafter legs rests on the Mauerlat, and the middle part on the supporting wall. The presence of additional support points allows you to unload the elements of the rafter system, removing from them, as well as from the walls of the building, alternating horizontal forces. Like roof beams, rafters begin to work only for bending. The frame with layered rafters becomes more rigid and durable compared to the structure in which the rafters of the unsupported type are used. And this despite the fact that in the first case, you can use a bar of a smaller section. And this helps to reduce the weight of the wooden structure and reduces the cost of purchasing lumber.

Installation of a hipped roof

The assembly of the rafter system must be performed in a strictly defined order. This is necessary in order to correctly install and fix all structural elements of the roof.

1. To redistribute the load that the roofing structure, wind and precipitation exert on the walls, a Mauerlat is laid on the outer walls. In individual construction, a bar with a cross section of at least 100x150 mm is used for these purposes. Anchor pins are used to fasten the longitudinal beams of the structure. They must be laid in the upper rows of masonry even at the stage of wall construction. Mauerlat waterproofing is performed using two layers of roofing material, which is laid on top of the load-bearing walls.

   
   Mauerlat is attached to the load-bearing wall with bolts or anchors

2. If it is necessary to install vertical supports, planks are laid on the supporting walls. For horizontal alignment of the elements of the rafter system, wooden linings are used. In the future, this will greatly simplify the installation of racks and purlins. If the capital partitions are not provided for by the building plan, then the vertical supports are mounted on the floor beams. To do this, they are reinforced by splicing two boards of 50x200 mm or using one beam of 100x200 mm.

   
   Support of vertical racks on beams is allowed only if the structure rests on a main wall

3. Expose the support posts. To align them, use a plumb line or a laser level, after which temporary supports are installed. Metal corners and plates are used to attach the vertical support to a bed or a horizontal beam.
4. Girders are laid on top of the racks. Traditional hip roofing requires the installation of one run, which, in fact, forms the ridge. Hip structures require the installation of four girders. As with the installation of racks, fastening is performed using metal corners and self-tapping screws.

   
   The ridge girder can be attached either directly to the rafter leg or by means of wooden pads

5. Preparing the rafters. The side rafter legs of simple gable roofs are mounted in the same way as the layered legs on a gable roof. First you need to make a template. To do this, from the side of the extreme support, a board is applied to the ridge of the same width as the rafters. Its thickness should not exceed 25 mm - the template should be light. On this board, a cut is noted, which is necessary for reliable support and an accurate fit of the rafter leg to the ridge bar, as well as a cutout corresponding to the place where it joins with the Mauerlat. The marked places are cut out and then used to quickly prepare the rafter legs.

   
   Making a template can reduce the time it takes to prepare the rafters for installation

6. When applying the manufactured sample to the purlin, it is necessary to check whether an exact fit of the rafter is necessary. If there are gaps, the cuts in the rafters are performed taking into account the amendments. After all the supporting legs are ready, they are set in 50–150 cm increments and attached to the Mauerlat and the ridge. Brackets are best suited for installation, but you can also take powerful metal corners.
7. As already mentioned, diagonal rafters are made from spliced ​​boards or a bar of an increased section. For their installation, you will also need a template, which is prepared in full accordance with the method described above. Since the rafters with one side adjoin the corner of the Mauerlat, and the other rest on the racks, the cut is performed at an angle of 45 ° to the plane.

   
   The layout of the rafters and rafters on the hip roof is performed according to the template

8. In the intervals between the rafters, the beads are attached. Their step corresponds to the distance between the rafters, and the diagonal legs and the Mauerlat are the support points. The load experienced by the rafters cannot be compared with the weight that falls on the rafters, so the first ones can be built from boards with a thickness of 30-50 mm. To speed up the installation, you will need a template with cuts on the side of the diagonal rafters and Mauerlat, but the cutouts on the half of the rafters must be made in mirror image.

   
   The use of metal fasteners makes the rafter system more rigid and stable

9. If necessary, filly are fastened to the rafters and the beggars. The ends of the rafter elements are cut along the cord.

   
   Attaching the rafters to the Mauerlat can be done in several ways

10. Strengthen the side rafters and side rafters. In the first case, vertical sprengels are used, and in the second, struts installed at an angle of 45 °. They are supported on benches or beams.
11. After the rafter system is assembled, a roofing pie is installed on top of it.

    
    The rafter system is prepared for the installation of roofing materials

Lathing and insulation

Before proceeding with the installation of the lathing, a vapor barrier is laid on top of the rafters, and, if necessary, rolled thermal insulation. On top, the layer of insulation is covered with a waterproofing film, which is mounted with an overlap of 10–20 mm wide and attached to the timber with a construction stapler. After that, counter-lattice slats are nailed to the rafters. If the roofing cake is mounted without insulation, then vapor barrier is not required - a layer of moisture-resistant material will be enough. Of course, additional slats are not needed in this case, since the boards supporting the roof will be attached directly to the rafters and rafter legs.

Depending on the type of roofing material, one of two types of lathing is used on hip roofs:

• solid;
• sparse.

The first is most often equipped with a soft roof and only in some cases - for arranging an attic space. Sheathing of this type is made of boards with a width of 100 to 200 mm and a thickness of at least 20-25 mm. Installation is carried out without gaps. In addition, the use of plywood sheets and OSB boards is allowed. Their advantage is an extremely flat surface, which allows you to lay the roofing material with minimal time and effort.

For a sparse lathing, the same boards are used as in the first case, but they are mounted with a gap. Since this type of base is used for laying slate, corrugated board, metal tiles and roofing iron, the distance between the individual boards must take into account the characteristics of the roofing material.

The lathing is fastened with nails, the length of which is equal to three times the thickness of the boards. If self-tapping screws are used for fixing, then a shorter threaded fastener with a length corresponding to double the thickness of the lumber can be used.

The wooden base of the roofing cake is mounted from the bottom up, with the first board of each slope being set parallel to the Mauerlat. First, the crate is stuffed on the hips, after which the protruding edges are cut off with a hacksaw flush with the diagonal ribs. Next, they proceed to fastening the lumber on the main slopes, releasing the edges of the boards for the nesting rafters. After that, the ends of the boards are sawn down in the same way as in the first case.

Video: we build a hip roof with our own hands

Typical hip roof project

When building a simple hip roof, you can use a typical project that was developed by specialists. Design documentation includes:

• technological map;
• roof plan;
• rafter system diagrams;
• drawings of sections and corner abutments;
• statement and specification with a complete list of materials used.

As an example, below is the documentation for a typical project of a hip roof for a 155 sq. m.

Gallery: drawings and diagrams of a hipped roof

The drawing indicates the exact dimensions of all roof elements At the base of the truss there are triangles. The rafters of the trapezoidal slopes rest on the long load-bearing walls of the structure. rafter fastenings wooden and metal products are used Fasteners allow transferring the load from one element of the system to another

Despite the seeming complexity of a gable roof, it is not much more difficult to build it with your own hands than a gable structure. It is only important to carefully understand the purpose of individual elements and the principles of building a rafter system. For the rest, the reliability and durability of the roof will still depend on the observance of the technology and the accuracy of the installation. As for the additional complications and costs, they will pay off with complete satisfaction from the work, which will make the building brighter and more attractive.

The construction of a four-slope roof frame is a complex process with characteristic technological features. During the construction, their own structural components are used, the sequence of work is different. But the result will amaze with its spectacular shape and resistance to repel atmospheric attacks. And the home craftsman can be proud of his personal achievements as a roofer. However, before deciding on a device of such a design, it is worth familiarizing yourself with the algorithm according to which the rafter system of a hipped roof is being built and with the specifics of its device.

The class of hipped roofs combines two types of structures that resemble a square and rectangular envelope in plan. The first variety is called hip, the second is hip. Against the background of pitched counterparts, they are distinguished by the absence of pediments, called tongs in roofing. In the construction of both variants of gable structures, layered and hanging rafters are used, the installation of which is carried out in accordance with standard technologies for the construction of pitched rafter systems.

Characteristic differences within the four-slope class:

• At the hipped roof, all four slopes are in the form of isosceles triangles, the tops of which converge at one highest point. There is no ridge as such in the tent structure; its function is performed by a central support in layered systems or the top of a hanging truss.
• At the hip roof, a pair of main slopes have a trapezoidal configuration, and the second pair is triangular. The hip construction differs from the hip counterpart in the obligatory presence of a ridge, to which the trapeziums are adjacent to the upper bases. Triangular slopes, they are also hips, adjoin the ridge with their apex, and their sides are docked with the inclined sides of the trapezoids.

Based on the configuration of the roofs in the plan, it is clear that tent structures are usually erected over square buildings, and hip structures over rectangular houses. Both soft and hard roofing materials are suitable as coverings. The characteristic square or rectangular shape is repeated by the drawings of the rafter system of a hipped roof with a clearly marked arrangement of elements in the plan and vertical projections of the slopes.

Often, hip and hip-roof systems are used together in the construction of one object or effectively complement gable, shed, broken and other roofs.

Structures with four slopes can be supported directly on the upper crown of a wooden house or on a Mauerlat, which serves as the upper strapping of brick or concrete walls. If you can find upper and lower supports for each rafter, the roof frame is constructed using layered technology.

Installation of layered rafter legs is easier and more accessible for an inexperienced home roofer who needs to take into account that:

• When the upper and lower heels of the rafters are rigidly fastened with metal corners or with the help of a supporting wooden lining, a reinforced fastening of the Mauerlat will be required, because the spacer will be transmitted to it.
• With a rigid fixation of the upper heel and a hinged fastening of the bottom of the rafters, it is not necessary to strengthen the fastening of the Mauerlat, because if the load on the roof is exceeded, the hinge mount, for example, on sliders, will allow the rafter to move slightly without creating pressure on the Mauerlat.
• When the top of the rafters is hinged and the bottom is rigidly fixed, the spacer and pressure on the Mauerlat are also excluded.

The issues of fixing the Mauerlat and the closely related method of installing the rafter legs according to the rules are decided at the design stage of the house. If the building does not have an internal load-bearing wall or it is not possible to build reliable supports for the central part of the roof, nothing will work except for the hanging rafter system assembly diagram. True, in most cases, the layered construction method is used, for the implementation of which it is necessary to provide a bearing support inside the building in advance.

In the device of rafter systems for hip and hip hip roofs, specific structural elements are used, these are:

• Diagonal rafter legs that form the backbone joints of the slopes. In hip structures, diagonals, they are also nipple rafters, connect the ridge girder consoles to the corners of the roof. In tent systems, the slant legs connect the apex to the corners.
• Narozhniki, or rafter half-legs, installed perpendicular to the cornices. They rest on diagonal rafters, are located parallel to each other, therefore they differ in lengths of different sizes. Narodniks form the planes of the hip and hip slopes.

Diagonal rafters and rafters are also used for the construction of valleys, only then concave roof corners are arranged, and not convex like hip corners.

The whole difficulty of constructing frames for roofs with four slopes lies in the installation of diagonal rafters, which determine the result of the formation of the structure. In addition, the slopes are required to firmly hold the load one and a half times greater than the ordinary rafter legs of pitched roofs. Because they work part-time as a skate, i.e. support for the upper heel of the wives.

If you briefly describe the procedure for building a layered frame for a hipped roof, then you can keep within several stages:

• Mauerlat device on brick or concrete walls. The process of installing the Mauerlat on the walls of a log or bar can be canceled, because it can be successfully replaced by the upper crown.
• Installation of a central support for a hipped roof structure or support frame for the main part of the hip roof.
• Installation of conventional layered rafters: pairs for a hipped roof and a series defined by a design solution for a hip structure.
• Installation of diagonal rafter legs connecting the corners of the systems to the top of the support or the extreme points of the ridge.
• Manufacturing to size and fastening of handcuffs.

In the case of using a hanging frame scheme, the start of the construction of a tent frame will be the installation of a triangular truss truss in the center. The installation of a series of roof trusses will be the beginning of the installation of the four-slope hip rafter system.

Construction of a hip rafter system

Let's analyze one of the common examples of a hip roof device with layered rafter legs. They will have to rely on the floor beams laid on top of the Mauerlat. Rigid fastening with a cut will be used only to fix the top of the rafter legs on the ridge run, so there is no need to reinforce the Mauerlat fasteners. The dimensions of the box shown in the example of the house are 8.4 × 10.8 m. The actual dimensions of the roof in the plan will increase on each side by the size of the eaves overhang, by 40-50 cm.

Mauerlat base device

Mauerlat is a purely individual element, the method of its installation depends on the material of the walls and the architectural features of the building. The method of laying the Mauerlat is planned according to the rules during the design period, because for reliable fixation of the Mauerlat it is recommended:

• To equip lightweight foam concrete, gas silicate and similar walls with a reinforced concrete belt, poured along the perimeter, with anchors installed during the pouring period for fastening the Mauerlat.
• Fold brick walls with one or two bricks along the outer edge so that a ledge is formed along the inner edge for laying a wooden frame. During masonry, wooden plugs are laid between the bricks to fasten the Mauerlat with brackets to the wall.

The Mauerlat is made from a bar with a size of 150 × 150 or 100 × 150 mm. If the operation of the under-roof space is expected, it is advisable to take the bars thicker. In a single frame, the timber is connected by oblique cuts. Then the connection sections are reinforced with self-tapping screws, ordinary nails or wood grouses, and the corners are reinforced with staples.

Overhead beams are laid on top of the Mauerlat, aligned to the horizon, constructed in the optimal way for a particular building. A bar with a section of 100 × 200mm is used. First of all, a beam is laid, passing exactly along the central axis of the building. In the example, the length of the timber for the construction of solid beams is not enough, therefore they are assembled from two beams. The docking point should be located above a reliable support. In the example, the support is an internal load-bearing wall.

The step between the floor beams is 60 cm. If the box being equipped does not differ in ideal parameters, as is the case in most situations, the distance between the beams can be slightly changed. Such an adjustment allows you to slightly "smooth out" the flaws in the construction. Between the extreme beams on both sides and the walls of the house, there should be a 90 cm gap, which is necessary for installing the outriggers.

Because floor beams on their own will be able to form only two eaves overhangs, short floor beams are attached to their ends - the outrigger. They are first installed only in the area of ​​the main part of the hip roof, exactly where the rafter legs are to be mounted. The stem is nailed to the Mauerlat, fastened to the beam with screws, large-caliber nails, pins, and the fasteners are reinforced with corners.

Construction of the ridge part

The central part of the hip roof is an ordinary gable structure. The rafter system for her is arranged according to the rules dictated by the technology for the construction of pitched roofs. In the example, there are some deviations from the classical interpretation of the sloping principle: the bed is not used, on which supports for the ridge run are traditionally installed. The work of the bed will have to be performed by the central floor beam.

In order to build the ridge part of the hip roof rafter system, you need to:

• Build a support frame for the rafter legs, the top of which will rest on the ridge girder. The run will be supported by three supports, the central of which is installed directly on the central floor beam. To install the two extreme supports, two transverse bars are first laid, overlapping at least five floor beams. Stability is increased by means of two struts. For the manufacture of horizontal and vertical parts of the supporting frame, a block with a section of 100 × 150 mm was used, the struts were made of a board of 50 × 150 mm.
• Make rafter legs, for which you first need to make a template. A board of suitable dimensions is applied to the installation site, lines of future cuts are drawn on it. It will be the template for the continuous production of rafters.
• Install the rafter legs, resting them with the cut on the ridge girder, and with the lower heel on the stem opposite.

If the floor beams were laid across the box, then the rafters of the main part of the roof would rest on the floor beams, which is much more reliable. However, in the example, they rely on the stem, therefore, additional mini-supports must be arranged under them. These supports should be positioned so that the load from them and the rafters located above is transmitted to the walls.

Then three rows of stems are mounted on each of the four sides. For the convenience of the implementation of further actions, the roof contour is drawn up with a cornice board. It must be nailed to the floor beams and outriggers strictly horizontally.

Installation of corner stems

In the space limited by the cornice board, there were corner sections that were not filled with the details of the rafter system. Here you will need angular stems, for the installation of which is carried out as follows:

• In order to indicate the direction of installation, we pull the lace. We stretch from the point of the conditional intersection of the extreme support of the frame with the floor beam to the corner.
• On top of the lace we put a bar in its place. Holding the bar, draw the cuts from below at the intersection of the floor beam and the corner joint of the cornice boards.
• We attach the finished stem with the sawn-off excess to the Mauerlat and to the floor beam with corners.

The remaining three corner stems are manufactured and mounted in the same way.

Installation of diagonal rafters

Diagonal, they are also slant, rafter legs are made of two boards sewn together with a section equal to the size of ordinary rafters. In the example, one of the boards will be positioned slightly higher than the second due to the difference in the angles of the hips and trapezoidal slopes.

The sequence of work on the manufacture and installation of mats:

• From the highest point of the ridge, pull the lace to the corners and to the center point of the slope. These are auxiliary lines along which we will mark the upcoming cuts.
• Carpenter's goniometer - small measure the angle between the lace and the upper side of the corner stem. This is how the angle of the bottom cut is determined. Suppose it is equal to α. The angle of the upper cut is calculated by the formula β = 90º - α.
• At an angle β, we cut off one edge of an arbitrary cut of the board. We apply it to the place of the upper attachment, aligning the edge of this blank with the lace. We outline the excess that interferes with a dense installation. You need to saw again along the marked lines.
• At an angle α, we saw off the lower heel on another cut of the board.
• We make the first half of the diagonal rafter using the templates for the upper and lower support. If the solid board is not long enough, two pieces can be spliced. They can be spliced ​​with a meter-long piece of inch planted on self-tapping screws, it should be placed on the outside of the constructed nipple leg. We install the finished first part.
• We do the second part of the rafters in the same way, but we take into account that it should be slightly lower than its first half. The section of joining the boards into one element should not coincide with the section of joining the boards of the first half of the slant.
• We sew two boards with nails at a distance with a step of 40-50 cm.
• Along the lace stretched to the center of the ramp, we draw a line along which it will be necessary to adjust the gash to dock it with the adjacent rafters.

Following the described algorithm, it is necessary to install three more diagonal legs. Supports should be installed under each of them at the point where the corner extensions are attached to the beams. If the span is more than 7.5 m, another support is installed diagonally closer to the ridge.

Manufacturing and installation of hip rafters

The lace between the top of the ridge and the center of the ramp is already stretched. It served as an axis for outlining the cuts, and now it is necessary to measure the angle γ along it and calculate the angle δ = 90º - γ. Without deviating from the proven path, we prepare templates for the upper and lower support. We apply the upper trim to the place intended for it and mark the cut lines on it for a tight fit between the diagonal rafters. Using the blanks, we make the central leg of the hip and fix it where it should be.

In the space between the corner extensions and the cornice board, we install short extensions to give rigidity to the structure and to ensure strong fixation of the extreme, shortest arms. Next, you should start making templates for the women themselves:

• We cut the board off at an angle δ and attach it to the attachment point to the diagonal rafter.
• We outline in fact the surplus that needs to be cut down again. The resulting template is used in the manufacture of all handcuffs, for example, the right side of the hip. For the left side, the top template will be filed from the opposite side.
• As a template for the lower heel, we use a piece of board sawn off at an angle γ. If all the previous steps were performed correctly, then this template is used to make the lower attachment points for all other women.

In accordance with the actual length and the "indications" of the templates, the knobs are made, which are necessary to form the planes of the hips and the parts of the main slopes that are not filled with ordinary rafter legs. They are installed so that the upper attachment points of the rafters to the diagonal rafters are spaced apart, i.e. the upper connecting nodes of adjacent slopes should not converge in one place. The hangers are attached to the rafter leg with corners, to the floor beams and outriggers as it is more reasonable and convenient: corners or metal toothed plates.

The hip roof technology is based on the already familiar hip principles. True, there is no ridge part of the rafter system in their design. The construction begins with the installation of a central support, to which the nesting rafters are attached, and then the bearers. If hanging technology is used in the construction of the roof with an envelope, then the finished truss is installed first.

We invite you to use our free online calculator for calculating building materials when installing a hip roof - go here and follow the instructions.

Helpful video instructions

Briefly, the video will introduce the sequence and rules for installing the rafter system of the hipped roof of the hip and hip categories:

Having familiarized yourself with the specifics of the device and having mastered the intricacies of installing roofs with four slopes, you can safely proceed to the implementation of plans for its construction.

The rafter system is a combination of all the supporting elements that form the frame on which the roofing cake lies. The strength and reliability of this foundation determines the ability of the roof to withstand wind and snow loads, to protect the interior from water and cold. In order not to resort to the expensive services of companies that perform roofing work professionally, we will tell you what the rafter system of a hipped roof consists of, what materials are required for its manufacture and how to assemble it.

Types of hipped roofs

The name "four-slope" unites several types of roofs, consisting of four planes, slopes:

Despite the external differences, the rafter systems of the hipped roof are made up of the same elements, guided by the same rules.

Types of truss systems

The rafter system of the four-pitched roof takes on a different look, depending on the initial conditions: the area of ​​the house to be covered and the internal layout. There are three types:

Which type of rafter system is suitable for a particular house is determined during the design period, making calculations and drawing up drawings.

Calculation of the slope of the slopes and the height of the ridge

Drawing up a project of a rafter system of a hipped roof begins with calculations that determine the geometry of the future structure:

To facilitate the design process of the rafter system of a hipped roof can be special computer calculator programs that only require entering the initial data: the size of the house, the number of slopes.

Calculation of loads

The next stage of design is to determine the composition of the elements of the rafter system and their section. For this, the calculation of the loads to which the four-slope structure is subjected is performed. They are divided into three types:

Summing up the values ​​of all loads, the total is determined, which, depending on the used roofing material, can reach 180-250 kg per square meter. Based on this figure, the number of elements of the rafter system and their cross section are determined, referring to the reference table. It is more convenient to calculate more complex systems in special programs, the result of which is a ready-made scheme of a four-pitched roof rafter system.

Main elements

The rafter system of a hipped roof consists of many components, mandatory and auxiliary:

1. Mauerlat. A beam with a section of 100x100 mm or 150x150 mm, evenly distributing the load along the perimeter of the bearing walls. The difference between a hipped roof is that its installation requires four Mauerlats, and not two, as for a gable.
2. Sill. A beam that serves as a support for the racks, which is used in a layered rafter system. He, like the Mauerlat, distributes the weight of the roof, but is located on the inner load-bearing wall.
3. Rafter legs. Elements from boards with a section of 50x150 mm or 100x150 mm, which carry the roofing pie and set the geometry of the slopes. In the construction of hipped roofs, ordinary, layered and rafters are used. Privates are arranged in pairs along the ridge girder, forming trapezoidal slopes. The oblique ones, diverging from the ridge to the two corners of the house, form end triangular slopes. And the rafters are supported by the upper part on the layered ones and have different lengths.
4. Ridge run. A beam supported by vertical posts, to which the rafters are attached. This is the highest point of the roof.
5. Racks. Vertical props that are installed on a bed. They support the ridge girder or the middle of the rafter leg.
6. Braces. Bars that are installed at an angle to the rafter legs to prevent them from bending.
7. Tightening and deadbolt. Horizontal lintels made of wood or metal, connecting pairs of rafter legs, reducing the bursting load on the walls. The crossbar is installed at the top of the rafters, in tightness at the bottom, often using floor beams.
8. Truss trusses. Sprengel is a vertical riser for nesting rafters. If there is nothing to rest against it, a tightening is installed between two adjacent sides of the house and a truss is attached with the help of metal corners.
9. Lathing. Base for decking roofing material. If the boards are nailed without gaps, the sheathing design is called solid. And if the boards alternate with a small gap - lattice. The lathing scheme depends on the type of roofing material.
10. Eaves. The part of the rafters that protrudes 40-50 cm beyond the perimeter of the house, protecting it from moisture.

Assembling the rafter system

Having in hand a drawing of the rafter system, you can begin assembly work. Since mainly natural wood is used as a material, it will not be superfluous to treat it with a deep penetration antiseptic to protect it from moisture and bacteria. Roofing masters pay attention to a number of features that should be taken into account when installing the rafter system of a hipped roof:

A well-designed and well-assembled rafter system is the basis for the long-term operation of a hipped roof, which will become a reliable weather protection, whether it is hip or hip!

Video instruction

Pitched roofs are quite popular in private suburban construction, and therefore the rafter system of a hipped roof, which has some design features, is of great interest to many.

It is this type of roof that is the preferred option for both a country cottage and a gazebo erected on the adjacent territory.

It should be noted that the hipped roof gives the structure a rather attractive appearance, and also allows you to get an additional attic room of a large area.

The rafter system of a hipped roof has a complex structure and its installation should be carried out only according to a preliminary calculation, the result of which should be a diagram.

The calculation of such a roof, both for a house and for a gazebo, can be done with your own hands if you use a special program developed specifically for these purposes.

Its rafter system allows several different options. The four-pitched roofs include the half-hipped roof, as well as the hipped roof, and each of them has its own specific characteristics and differences.

Some types of these types of rafter systems, the installation of which can be done by hand, are shown in the photo below.

Features and types of hipped roof type

The device and design of the rafter system for a four-pitched roof type primarily depends on the configuration.

Currently, the most common are the hip, hip, and half-hip structures of the rafter system, which can be used both for a private house and for a gazebo.

Each of them has both advantages and disadvantages.

In any case, the rafter system of a hipped roof involves a calculation that is made depending on the type selected.

The hip type of rafter system is quite popular in private construction. Its design is quite resistant to various external influences and involves the device and installation of trapezoidal slopes.

As a rule, its installation is carried out using several separate rafters that run from the two upper points. This type of rafter system can also be used to build a gazebo.

Hip roof options can be seen in the photo below.

Also quite often there is a half-hip roof, the design of which vaguely resembles a gable roof.

The advantage of this type of rafter system is the ability to equip a vertical window in the upper attic area.

Its design assumes the absence of a sharp protrusion, which allows it to perfectly withstand sufficiently strong wind loads.

In addition, in some cases, the half-hip rafter system makes it possible to equip full glazing of the upper space.

The hipped roof also belongs to the hipped roof, but for its arrangement it is necessary that the structure is made in the form of a square near the walls of the building.

The device of this type of roof implies, due to a certain design of the slopes, the formation of a triangle with equal sides. Very often, a hipped roof is installed on gazebos.

Any of the types of this type of rafter system implies an accurate calculation, on the basis of which the installation is carried out by hand.

Design features

A four-pitched roof, regardless of its type, necessarily has a frame, the design of which assumes the presence of a sufficiently large number of various elements.

Each of them has a specific purpose and must meet its functional requirements.

In order for such a roof to withstand all possible loads during its operation, it is necessary to accurately calculate the capabilities of each of its constituent elements.

Such a calculation is a rather complex calculation that is not always possible to do it yourself.

It is best to entrust the calculation of a hipped roof to qualified professionals who have professional training.

The calculation can be done independently, but for this you will have to use a special program.

The easiest way to make such a calculation is for a gazebo, since its design has a simpler shape and involves the use of fewer elements.

When calculating the roof frame, it is important to avoid critical errors, as this can lead to serious consequences during its subsequent operation.

In the event that mistakes are made, their correction can lead to serious financial investments and an increase in the cost of the entire construction.

First of all, when calculating the roof frame, it is important to determine the angle of inclination of its slopes. Calculations show that the higher the angle of inclination, the more building materials will be required.

Also, when calculating the roof, it is imperative to take into account the fact that the lower the angle of its inclination, the more powerful the structure of the frame itself should be.

A correctly calculated calculation will make the rafter system better and more powerful.

A semi-hip, hip or hipped roof of a four-slope type are presented in the photo posted above.

Types and features of rafter systems

The device of any type of four-pitched roof frame can differ not only by the bay window, but also by the presence of certain constituent elements.

So, its installation involves the arrangement of a Mauerlat, a run, as well as a support board. In addition, the roof frame should include puffs, cuffs, and directly, the rafters themselves.

The installation of a hipped roof requires the arrangement of the lathing, as well as some other required elements.

The roof frame at the gazebo is a little simpler and this is due, first of all, to its design features. The installation of a hipped roof is shown in the video below.

In any case, in order to install the roof frame of a house or gazebo, it is necessary to develop a plan for the rafter system and this should be done as accurately as possible.

Both the half-hip and any other four-pitched roof consists directly of the frame and the rafter system itself, on which the roofing pie will subsequently rest.

An important point when arranging this type of roof with your own hands is the uniform distribution of the expected load over the entire surface of its structure and then onto the walls and directly onto the foundation of the structure.

This can be achieved not only by the correct design of the roof frame, but also by its installation. For this, rafter systems of various types can be used.

Their choice mainly depends on the size of the house under construction, in addition, the presence of internal walls of the load-bearing type or additional supports is taken into account.

In any case, the installation of the roof can be carried out using hanging or layered rafters, as described in detail in the video below.

Structures of truss systems

Hanging type rafter systems are often used. This type of construction involves the arrangement of two independent supports, which do not imply any intermediate support.

Such rafter systems work in both bending and compression. Also, the hanging type of structure of the rafter system creates a horizontal force, which is accordingly transmitted to all load-bearing walls.

This type of load can be reduced by using special ties, which are jumpers made of wood or metal, connecting all wooden legs.

When erecting an attic or attic roof, such puffs are installed at the base of the legs. If such a tightening is attached above the base of the rafters, then its main function is only securing.

It should be noted that the higher such a tightening is set, the more durable all the constituent elements of the rafter structure should be.

In those buildings in which a load-bearing middle wall is provided, or special supports are additionally installed, as a rule, a rafter system is equipped, which provides for the arrangement of layered rafters.

Such layered rafters with their lower parts rest directly on the Mauerlat, which must be laid over the entire surface of the outer walls of the house. In addition, in such a rafter system, the middle part is additionally strengthened in the middle part of the house.

The design of the layered rafter system works in bending and has less weight than hanging rafters, which means that less building materials are used for its device.

In addition, the rafter system, which is made using layered rafters, has a higher strength, and, accordingly, rigidity.

Some installation features

Any hipped roof, even if the device is designed for a gazebo, requires a complex structure, while they can be equipped with a bay window of various shapes.

At the base of these types of roofs is a triangle, which determines their high rigidity and stability.

The main elements of such a roof, which bear the main load on themselves, are the rafter legs, the design and installation of which should be given special attention.

When assembling such a roof with your own hands, it is recommended to follow the rules and construction technology with maximum accuracy.

In addition, you should use only high-quality building materials that have the required strength and reliability.

When erecting a four-pitched roof, special attention should be paid to all its corner elements that experience the maximum number of loads.

If it is necessary to perform splices of some frame elements, they should be additionally reinforced with appropriate struts and struts, making it possible to reduce the overall load.

In general, a four-pitched roof is a structurally complex element of a house, which must be made in accordance with all requirements.

A roof of four slopes - what is it good for? The numerous operational advantages of this type certainly outweigh the disadvantages. Is the hipped roof truss system as simple as many newcomers to the construction business think? You will definitely find out soon! We will describe important nuances and features of the stages of erection of a hip roof in this article.

What you need to know about hipped roof truss systems?

There are two options for hipped roofs: hip roof and hip roof. The first type has the shape of a rectangular envelope, consisting of two main trapezoidal slopes and a ridge, and two pediment (side) slopes - triangles:

A hipped roof is four identical isosceles triangles connected at one upper point (resembles a tent):

Both options provide for the installation of both layered and suspended rafters, which are installed using standard technologies.

How to choose the type of rafter system for a 4-pitched roof?

In the absence of a central roof support, the choice is made in favor of a hanging rafter system. If you can find upper and lower supports for each rafter, then a layered structure should be chosen. This option is easier and more accessible for non-professional craftsmen. You just need to remember two main conditions: with a rigid fastening of the bottom and top, you need a reinforced Mauerlat, since the thrust is transferred to it; with a hinged mount or semi-rigid connection (for example, the top is articulated, and the bottom is rigid or vice versa), the Mauerlat does not need to be reinforced:

The choice of one of the types of hipped roof should be determined by the shape of the house itself. Hip rafters are erected for square houses, hip rafters for rectangular ones. Also, you can find complex multi-slope roofs of a combined type, which contain both hip and hip elements.

Both hip and hip structures retain the basic functions of a gable roof (for example, the possibility of arranging an attic) and look very aesthetically pleasing:

Why is a hipped roof more popular than a gable?

"Why then the extra headache and difficulties?" - you ask: "After all, you can build a simple gable roof much faster and cheaper." Here, the masters emphasize some important points in favor of choosing exactly four slopes for the roof:

1. High wind resistance. The four-pitched roof has no gables, all of its planes are inclined towards the ridge. Such a structure minimizes the impact of strong winds and reduces possible destructive consequences to "0".
2. The most successful load distribution. The multi-slope roof withstands the maximum amount of precipitation, since the gentle slopes take part of the main load. Therefore, sagging, deformation and destruction of the rafter system, in this case, have a minimal likelihood.
3. The availability of a choice of any method of roof insulation. Straight gables require a special approach when choosing the type of roof insulation, as they are located vertically and are subject to blowing by the wind. The gentle slopes of the hip and tent systems allow you to uniformly insulate the roof with any available material.

In addition to the listed "pluses", a roof with four slopes perfectly conserves heat, can be clad with any roofing material and always has a neat appearance.

The device of the four-slope rafter system

The four-slope rafter structure consists of the following elements: Mauerlat, ridge beam, central and hip rafters, slant legs, as well as benches, racks, crossbars, struts and other reinforcing details. Let's take a look at the most basic elements.

I. Mauerlat

Mauerlat is the most important design detail, since the entire rafter system is supported on it. It is a powerful wooden beam 100x200, 100x250, 100x100, 150x250, 200x200 cm. The Mauerlat is made of solid quality wood, mainly conifers. The rafter system of a hip roof, like any multi-pitched roof, requires a solid fastening of the base bar. The order of installation of the Mauerlat in this case: the formation of a monolithic foundation at the end of the load-bearing walls with the installation of spiers; laying waterproofing; processing and installation of Mauerlat around the perimeter of the entire house; reinforced with anchors and other fasteners for maximum reliability of the base.

Mauerlat can be laid on the edge of the wall, or in the pocket provided for brick laying on the inside of the load-bearing walls.

II. Slant legs

Slant legs are the four corner rafters that rest on the edges of the ridge and the corners of the Mauerlat. They are the longest among all the rafter legs of the system, therefore they must have a section of at least 100x150 mm for maximum rigidity.

III. Ridge bar

A ridge girder is a horizontal beam that connects all the rafters, the top of the rafter system. The beam must be strengthened with uprights and struts. The ridge should be located strictly parallel to the plane of the attic floor and perpendicular to the uprights.

IV. Rafters

Rafters for a hipped roof are divided into: central (mounted on the Mauerlat and the ridge); main hip (attached to the ridge axis and Mauerlat); intermediate and shortened (installed on slant legs and Mauerlat, connect the corners of the slopes).

V. Reinforcing elements

Additional reinforcing elements include ridge posts, crossbars or floor beams, rafter leg struts, wind beams, etc.

Diy rafter system for a hipped roof

Consider the step-by-step process of erecting a truss structure. For clarity, we have chosen the most popular option - a hip roof. The rafter system hip roof, a diagram of which, step by step, is presented to your attention below:

Step I: Create the project

To depict your version of the hip roof in the drawing, it is necessary to calculate the height, length, slopes of the slopes and the area of ​​the roof. This is necessary for a clear and high-quality implementation of the project and the selection of the required amount of consumables:

Calculations should start with the choice of the angle of the roof slopes. The optimal slope is considered to be an angle of 20-450. The slope must correspond to the climatic features of the region. So, in especially windy areas, the slope should be minimal, and for areas where precipitation is frequent and abundant, the steepest slope angle is required. In addition to the weather environment, you need to take into account the roofing material that you plan to use. For a soft roof, the degree of inclination should be less, for a hard roof, more.

And one more small but important nuance on this issue - it is better to make the slope angle the same for all four slopes. So the load will be evenly distributed, and the structure will be as stable as possible, and the aesthetic appeal will remain “at its best”.

Now, knowing the angle of inclination and width of the house, we can use simple mathematics to calculate the height of the ridge, the length of the rafter legs, racks and other details of the rafter system. When calculating the length of the rafters, do not forget to take into account the eaves overhang (as a rule, its length is 40-50 cm).

The roof area for the purchase of the required amount of roofing material is calculated as the sum of the areas of all the slopes of the structure.

How to draw up a roof drawing correctly?

• Select the scale of the drawing and transfer the dimensions of the house to scale on a sheet of paper;
• Next, we transfer the selected dimensions of our roof to the diagram: the height of the ridge, its length, the number and size of rafter legs, struts, racks and all the details, in accordance with the calculations made earlier;
• Now you can calculate all the necessary materials and start looking for them.

Step II: Getting Started

To erect a roof frame, you will need standard tools and equipment: drills, screwdriver, jigsaws, hammers, chisels, etc. We already know the required amount of materials for the rafter system, so we can make a purchase. The lumber for the frame should be solid, not have cracks, wormholes, have a light shade, without gray or yellow bloom, smell like fresh wood. Damp wood should not be laid on the roof immediately, it must be dried, treated with an antiseptic solution and dried again. The moisture content of the tree should not exceed 20%.

Step III: Mounting the Mauerlat

Mauerlat is the basic part of the entire rafter system. It transfers the spacer loads to the load-bearing walls of the house. Installing a Mauerlat for a hipped roof is no different from similar structures with two or one slope. This process is described in maximum detail in our previous articles.

The base beam, the parameters of which are described above, are placed on the armpole and high-quality waterproofing. If it is necessary to connect the Mauerlat, then the bars are cut in half of the section and overlapped using strong fasteners.

Step IV: Laying the slats or floor beams

If there are load-bearing walls inside the house, then on their ends it is necessary to install rods - the basis for the support racks of the roofing system. If there are no more load-bearing floors in the house, then the attic floor is covered with reinforced beams, on which the supports for the roof are subsequently installed, and then the attic floor pie is laid.

The beams must have a cross section of at least 100x200 mm. The step between them is 60 cm. You can slightly adjust this figure, depending on the characteristics of your home. The distance between the extreme beams and the Mauerlat should not be less than 90 cm. This distance is used for the installation of the semi-beams of the eaves overhang (extension). The stems are attached to the two outer beams using strong anchors and reinforced metal corners.

Step V: Installing Support Posts, Purlins and Ridge

The uprights are an important part for supporting the structure, they redistribute the weight of the rafter system onto the beds or floor beams. The racks are installed strictly perpendicular to the plane of the bed. In hipped roof systems, the supports are installed under the ridge beam (hip roof) or under the corner rafters (hip roof):

The uprights must be securely attached to the base using metal plates and reinforced corners. The purlins are installed as an additional support for the racks. In a hipped roof, the girders are rectangular, and for hips, these are ordinary ridge girders.

After we have made sure of the correctness of the installed supports (using a meter and a level), you can fasten the upper ridge beam. It is mounted on vertical posts and reinforced with reliable metal fasteners (plates, corners, anchors and self-tapping screws). Now we take on the corner stems:

Step VI: Installing the rafters

The first is to install the side rafters, which rest on the ridge beam and the Mauerlat (or are fixed with an extension). To do this, you need to make a template rafter with appropriate cuts. We attach the rafter leg to the ridge, mark the place where the rafters were washed down with a pencil, then mark the place where the rafters were washed down for docking with the Mauerlat and make the saws. Re-attach the rafter to the supports to make sure that the docking is correct and to correct any deficiencies. This pattern can now be used to make all side rafters. The installation of the rafter legs of the main slopes is carried out according to the general rules described in the device of the gable rafter system (see article and video).

Diagonal (corner) rafters are mounted next. Their upper edge is installed on the rack and joins the edge of the ridge bar. Before this, measurements are made and the corresponding saws of the rafter legs. The lower end of the diagonals is fixed at the corners of the Mauerlat:

Since the diagonal rafters are longer than all other legs, they require additional support. This function is performed by trusses - support beams that are installed under each diagonal leg, in its lower quarter (this is where the greatest load occurs). Sprengel, like the ridge posts, are installed on supporting corner beams located in the plane of the floor beams.

Between the corner ribs, the space is filled with auxiliary rafter legs - wedges. The lower part of them rests on the Mauerlat, and the upper part on the diagonal rafter leg. The step between the rafters should be equal to the step between the side rafters (50-150 cm).

Step VII: lathing

It remains to complete the final stage of the formation of the roof skeleton - the installation of the lathing. These are boards or bars of 50x50 mm, which are attached to the rafters parallel to the ridge girder and the Mauerlat. The pitch of the sheathing boards is 50-60 cm. This is quite enough for laying the roofing cake. When a soft roof is provided, the lathing is placed in 2 layers (counter lathing and lathing).

Finally, a few videos:

So, we have described the installation of the four-pitched roof truss system, its basic principles, and even went a little deeper into some of the nuances. Hip and hip designs - although not the easiest, but quite feasible option for every novice craftsman. Especially if he has good helpers. We wish you success in your work!