Hip roof with sloping slope. He cut down the rafters of the hip roof. Installation of support posts

The roof protects the building from the penetration of adverse atmospheric phenomena into the premises. To guarantee reliability and durability roofing structures, you need to choose the right type of roof and know all its structural elements. Bears the load from the coating and snow cover rafter system. Most often, a hip roof becomes the best option. But what is she?

What is a hip

The hip roof design is a hip roof system. In the center of which there is a ridge or simply a connection point between the slopes. The roof slope is an inclined surface,

This type is best suited for covering buildings that are close to square in plan, that is, having a large width. During construction there are no gables, the walls around the entire perimeter are the same height. The optimal value of the inclination angle in degrees will be from 20 to 45.

Its main parts are:

Structural elements of a hip roof

The design of the hip roof rafter system requires the presence of the following elements:

1. Rafter legs (rafters)– the main load-bearing structures (available only for rectangular hips) are inclined beams resting on the mauerlat at one end and on the ridge crossbar at the other.
2. Narozhniki– rafter legs resting with their upper and lower ends on the slanted legs. The Mauerlat often acts as a lower support. These elements are the main structural parts of a square hip roof. With a rectangular building plan, they are used together with conventional rafters, the pitch and cross-section are the same.
3. Sloping legs– diagonal rafters forming end slopes. At the lowest point they rest on the corner of the building. They usually have a larger cross-section than ordinary rafter legs. The narcissists lean on them.
4. Ridge transom– a horizontal beam located in the central part of the building (absent if the building is square). The design of a hip roof requires the presence of racks along it (with a gable roof, the support occurs on the gables). It is the upper support for inclined beams.
5. Mauerlat– a beam installed along the edge of the wall from the inside. Provides lower support for rafters, evenly distributes the vertical component of the load along the walls and absorbs the horizontal component (thrust). In a timber or log house, the upper crown of the wall structure serves as the mauerlat.
6. Struts– inclined posts supporting rafters, sloping legs or crossbars. Intermediate supports make it possible to reduce the cross-section of load-bearing elements. The hip roof rafter system involves installing struts at an angle of 60 or 45 degrees relative to the horizontal plane.
7. Racks– vertical intermediate supports.
8. Sprengels– horizontal beams laid diagonally in the corner of the building. They provide support under the post installed to support the mowing leg. This design transfers the load to perpendicular walls and is used when it is not possible to install a rack on the floor. For example, it is impossible to install a support post in the middle of a reinforced concrete slab, since the slab can withstand a certain load, the main component of which is the mass of furniture, equipment and people.
9. Fight– a horizontal element that tightens the rafters, preventing them from moving apart, can be located at the level of the mauerlat or higher.
10. Lathing- boards or bars of small cross-section, laid perpendicular to the rafters on top of them. Serve as a basis for roofing material. A do-it-yourself hip roof is often erected with the installation of sparse sheathing (through one board), but you need to remember that in especially critical places (valleys, eaves) the sheathing is continuous.
11. Counter-lattice– bars or boards of small cross-section. They are not always used in roof construction. They are installed on top of the rafter legs, parallel to them under the sheathing. They are needed to raise the sheathing above the insulation between the rafters, thereby providing the necessary ventilation gap.
12. fillies- boards attached to the lower end of the rafters, providing the necessary overhang of the cornice.

Some of these elements are missing in the design of a simple roof; the required structures for a hip are:

• connoisseurs;
• slanted legs;
• Mauerlat;
• sheathing.

Preparatory work

Before making a hip roof, you need to make several design decisions, namely:

• rafter pitch;
• cross-section of rafters and slanted legs;
• roof slope angle.

The pitch of the rafters depends on the purpose of the roof space and the width of the building. The larger the span of the rafter leg, the smaller the step you will have to take. If the space under the roof will be used as an attic floor or a heated attic, additional insulation will be required.

Insulation is carried out using three types of materials, depending on which the step is selected:

• rigid mineral wool slabs - rafter pitch 58 or 118 cm;
• expanded polystyrene (foam or extruded) – rafter pitch – 60 cm;
• polyurethane foam (foam) – any step.

These values ​​are due to the convenience of workers. If we take a load-bearing structure pitch of 58 cm when using mineral wool, then convenient installation of standard 60 cm wide slabs will be ensured.

The manufacturer recommends that the thermal insulation material be several centimeters wider than the clean distance between the rafter elements, this will ensure the tightest possible fit and prevent the appearance of cracks and cold bridges. The purpose of the 118 cm size involves laying the slabs in two stripes in width.

When using expanded polystyrene with a standard width of 60 cm, installation with a spacer is not required. The material is held between the supporting structures by glue, special nails and the bottom sheathing. The gaps between wooden elements and filled with slabs of thermal insulation material polyurethane foam or sealant.

Polyurethane foam in the form of foam eliminates the requirements for rafter spacing. The material can take any form given to it, which provides freedom of action in this matter.

If installed skylights, their sizes also need to be taken into account. The clear distance between the inclined beams is 4-6 cm greater than the width of the window. If roof insulation is not provided, choose a convenient rafter spacing, usually 1 meter.

The cross-section of the rafters is taken by calculation, but in general the following values ​​can be specified:

• 5x15 cm for spans up to 3 m;
• 5x20 cm for spans up to 4 m;
• 7.5x17.5 for spans up to 5 m;
• 7.5x200 for spans up to 6 m.

The values ​​are given for a rafter pitch of 0.9. As the distance increases, the cross section must also be increased. The cross-section of the oblique legs is also taken a little larger.

Installation

A do-it-yourself hip roof is a feasible task, but you need to know the main components connecting the structures.

The connection of the rafter legs at the top point depends on the type of rafters. They can be:

• layered;
• hanging.

Layered ones rest on the crossbar on top. To do this, a notch is made in the horizontal beam. Fastening is done with nails.

Hanging rafter legs provide for the absence of a crossbar. They are most often used when it is necessary to organize a free layout and there is no central wall. In this case, there is no support under the joint. The inclined beams are fastened together with nails. Additionally, at the junction, wooden overlays 22-25 cm thick are provided on both sides of the rafter legs. These linings are tightened using studs or bolts.

To secure the rafters at the lowest point, a notch is made in the Mauerlat. Inclined elements are installed and secured using nails or metal corners. The splices are connected to the mowing elements end-to-end, at the same level.

To resist the roof against wind loads that try to tear it off, wire twists are provided that connect the lower end of the rafters to the wall. The twist is fixed into the wall using a ruff (fastening device).

When constructing walls from wooden materials Instead of twists, staples can be used. Twists or staples are installed on each rafter leg or every other one.
If you build the rafter system correctly with the correct selection of the cross-section and pitch of the rafters, the roof will last a long time.

We already talked about the hip roof in one of the previous articles on the site. There the roof structure was described with the rafters resting on the mauerlat. After publishing the article, I received many requests to show how to make a hip roof with rafters supported on floor beams, and also to answer the question whether it is possible to make a hip roof with different slope angles.

Thus, I wanted to “kill two birds with one stone” with one example. Now we will look at the design of a hip roof with the rafters supported on the floor beams and with different slope angles.

So, let’s say we have a house box made of thermal blocks (polyblocks) 8.4x10.8 meters.

STEP 1: Install the Mauerlat (see Fig. 1):

Picture 1

STEP 2: We install long floor beams with a section of 100x200 cm in increments of 0.6 meters (see Fig. 2). I will not dwell on the calculation of beams any further.

Figure 2

The very first to install are the beams that run strictly in the middle of the house. We will be guided by them when installing the ridge beam. Then we put the rest with a certain step. For example, we have a step of 0.6 meters, but we see that there are 0.9 meters left to the wall, and another beam could fit, but it doesn’t. We leave this span specifically for “removals”. Its width should not be less than 80-100 cm.

STEP 3: We install the stem. Their pitch is determined when calculating the rafters, about which a little later (see Fig. 3):

Figure 3

For now we are installing only the stems corresponding to the length of the ridge, which will be equal to 5 meters. Our ridge length is greater than the difference between the length and width of the house, which is 2.4 meters. What does this lead to? This leads to the fact that the corner rafter will not be located at an angle of 45° in plan (in the top view), and the angle of inclination of the slopes and hips will be different. The slopes will have a gentler slope.

It is enough to secure the stem on the Mauerlat with nails. We attach them to a long floor beam, for example, like this (Fig. 4):

Figure 4

There is no need to make any cuts in this node. Any cut will weaken the floor beam. Here we use two LK type metal rafter fasteners on the sides and one large nail (250 mm) driven through the beam into the end of the extension. We hammer in the nail very last, when the stem is already fastened to the Mauerlat.

STEP 4: Install the ridge beam (see Fig. 5):

Figure 5

All elements of this structure except the struts are made of 100x150 mm timber. Struts made of boards 50x150 mm. The angle between them and the ceiling is at least 45°. We see that under the outer posts there are beams resting directly on five floor beams. We do this to distribute the load. Also, to reduce the load on the floor beams and transfer part of it to the load-bearing partition, struts were installed.

We determine the installation height of the ridge beam and its length for our home ourselves, making a preliminary sketch on paper.

STEP 5: We manufacture and install rafters.

First of all, we make a template for the rafters. To do this, take a board of the required cross-section that is suitable in length, apply it as shown in Figure 6 and make markings using a small level (blue line):

Figure 6

The height of the block that we placed on the stem to mark the lower cut is equal to the depth of the upper cut. We made it 5 cm.

Using the resulting template, we make all the rafters of the slopes, resting on the ridge beam, and secure them (see Fig. 7):

Figure 7

In such structures, where the rafters are supported not by long floor beams, but by short extensions, we always place small supports under the rafters above the mauerlat, forming a kind of small triangle and relieving the attachment point of the extension to the beam (see Fig. 8):

Figure 8

There is no need to bring these supports further inside the roof, much less place them at the junction of the extension with the beam. Most of the load from the roof is transmitted through them (this can be seen in the calculation program) and the floor beam may simply not withstand it.

Now a little about calculations. When choosing the section of rafters for a given roof, we calculate only one rafter - this is the slope rafter. It is the longest here and its angle of inclination is less than the angle of inclination of the hip rafters (explanation - we call a roof slope in the shape of a trapezoid a slope, a hip - a roof slope in the shape of a triangle). Calculations are made in the “Sling.3” tab. Example results in Figure 9:

Figure 9

Yes, I forgot to say. Who has already downloaded this calculation program from my website before December 1, 2013? There is no “Sling.3” tab. To download the updated version of the program, go to the article again at the link:

This article has also been slightly adjusted thanks to feedback from some readers, for which special thanks to them.

STEP 6: We add an extension and attach wind boards (see Fig. 10). We add enough stems to leave room for attaching the corner stem. For now, we simply sew the wind boards at the corners together, controlling their straightness. Check visually to see if the corners are sagging. If so, place temporary supports under them directly from the ground. After installing the corner extensions, we remove these supports.

Figure 10

STEP 7: We mark and install corner offsets.

First we need to pull the string along the top of the floor beams, as shown in Fig. 11

Figure 11

Now we take a beam of suitable length (the cross-section is the same as for all stems) and place it on top of the corner so that the lace is in the middle of it. From below on this beam we mark the cut lines with a pencil. (see Fig. 12):

Figure 12

We remove the lace and install the timber sawn along the marked lines (see Fig. 13):

Figure 13

We attach the corner extension to the Mauerlat using two roofing corners. We fasten it to the floor beam with a 135° angle and a large nail (250-300 mm). If necessary, bend the 135° corner with a hammer.

This way we install all four corner offsets.

STEP 8: We manufacture and install corner rafters.

The hip roof that I described earlier had the same angles of slope and hips. Here these angles are different and therefore the corner rafter will have its own characteristics. We also make it from two boards of the same section as the rafters. But we sew these boards together not quite usually. One will be slightly lower than the other (about 1 cm, depending on the difference in the angles of the slopes and hips).

So, first of all, we pull 3 laces on each side of the roof. Two along the corner rafters, one along the middle hip rafter (see Fig. 14):

We measure the angle between the lace and the corner stem - the bottom cut. Let's call it “α” (see Fig. 15):

Figure 15

We also mark point “B”

We calculate the angle of the upper cut β = 90°- α

In our example α = 22° and β = 68°.

Now we take a small piece of board with the cross-section of the rafters and saw one end on it at an angle β. We apply the resulting blank to the ridge, combining one edge with the lace, as shown in Fig. 16:

Figure 16

A line was drawn on the workpiece parallel to the side plane of the adjacent rafter of the slope. Using it we will make another cut and get a template for the top cut of our corner rafter.

Also, when we apply the workpiece, we need to mark point “A” on the rafters of the slope (see Fig. 17):

Figure 17

Now we make the first half of the corner rafter. To do this, take a board of suitable length. If one board is missing, we sew two boards together. You can sew it temporarily by cutting an inch about a meter long onto self-tapping screws. We make the top cut according to the template. We measure the distance between points “A” and “B”. We transfer it to the rafter and make the bottom cut at an angle “α”.

We install the resulting rafter and secure it (see Fig. 18):

Figure 18

Most likely, due to its length, the first half of the corner rafter will sag. You need to place a temporary stand under it approximately in the middle. It is not shown in my drawings.

Now we make the second half of the corner rafter. To do this, measure the size between points “C” and “D” (see Fig. 19):

Figure 19

We take a board of suitable length, make the top cut at an angle β, measure the distance “S-D”, make the bottom cut at an angle α. We install the second half of the corner rafter and sew it to the first with nails (100 mm). We drive the nails at intervals of approximately 40-50 cm. The result is shown in Fig. 20:

Figure 20

The upper end of the second half of the corner rafter needs to be sawed down again. We do this with a chainsaw right on the spot (Fig. 21):

Figure 21

In the same way, we manufacture and install the three remaining corner rafters.

STEP 9: We install racks under the corner rafters. First of all, it is imperative to install a stand resting on the junction of the corner extension with the floor beam (see Fig. 22):

Figure 22

If the length of the span covered by the corner rafter (its horizontal projection) is more than 7.5 meters, we install more racks at a distance of approximately ¼ of the span from the top point of the corner rafter. If the span is more than 9 meters, add racks in the middle of the corner rafter. In our example, this span is 5.2 meters.

STEP 10: We install two central hip rafters. At the beginning of the 8th step, we already pulled the laces to measure them.

We make the rafters in this way - we measure the angle of the lower gash “γ” with a small tool, calculate the angle of the upper gash “δ”:

We measure the distance between the points “K-L” and make a rafter along it. We file the ends at the angles we have determined. After this, the upper end needs to be filed down (sharpened) again, taking into account the angle “φ”, which we also measure using a small tool (see Fig. 23):

Figure 23

STEP 11: Add offset to the corners. We make the outermost extensions, which do not reach the mauerlat, lightweight, from a 50x200 mm board (see Fig. 24):

Figure 24

STEP 12: We install spigots. I described in detail how to make awnings in the first article about the hip roof. Here the principle is absolutely the same, so I will not repeat it (see Fig. 25):

Figure 25

We attach the corner rafters to the corner rafters using a 135° metal corner, bending it if necessary.

After installing all the frames, all we have to do is hem the cornices from below and make the sheathing. We have already talked about this many times.

Construction of X-shaped (octagonal) roofs.

Construction of a T-shaped roof of a house.

Installation of an L-shaped roof with gables of various widths.

L-shaped roof of the house with equal gables.

Do-it-yourself hip roof for a house.

Look, this way you can “slow down” your electric meter by 2 times! ...Completely LEGAL! You need to take the one closest to the meter...

Suburban plots are not large in size. Therefore, many people build small houses and increase their living space by creating additional living spaces in the attic. This is possible if the hip roof rafter system is installed correctly.

1 What is a hip roof?

This roof is made in the form of four slopes. Two of them are classic side ones in the form of a trapezoid, and two more triangular ones at the ends of the roof. Unlike a hip roof, where all four slopes converge at one point, a hip roof has two peaks connected by a ridge.

Hip roof with four slopes

It is the side triangular gables, which are made with a slope, that are called hips. A gable roof also has triangular end gables, but they are located strictly vertically; on a hip roof, these slopes are inclined, which is hallmark this type of roof.

Gable hip roof

A hip roof is called if the end slopes, starting from the ridge, reach the outer wall, that is, the eaves. But there are options when the slope is interrupted and in one place turns into a vertical plane. Then such a roof is called half-hip or Dutch.

2 Knots and elements of a hip roof

By installation method and use different material such roofs can be classified as complex structures. In general, the design of a hip roof consists of a mauerlat, ridge beams, rafters - corner, short and intermediate.

Mauerlat is a wooden beam mounted around the entire perimeter of the house at the very top of the walls. It serves for the correct transfer and distribution of loads exerted by wind, snow cover, the weight of the roof and the rafter system itself on the load-bearing walls of the building. This element is the connecting top frame for walls made of piece materials - bricks, concrete blocks.

Mauerlat hip roof

The mauerlat is not suitable for walls made of logs or timber. Its role is played by the upper crowns of the log house.

The ridge beam is the main element of the rafter system that connects all the roof slopes into a single structure. It must be the same cross-section as the rafter legs. Otherwise, in the future, distortion of the entire truss structure and the roof as a whole may occur.

Corner rafters, otherwise called slanted or diagonal rafters, are the basic strength parts that connect the corners of the building frame with the ridge beam. To make them, you will need a board equal in thickness to a ridge beam. One end of it is attached to the ridge, the other rests on the mauerlat. Depending on the roof project, a different number of such rafters is used, but not less than four.

Hip roof corner rafters

Short rafters can vary in length, but when assembling the roof structure, they are all brought out at the same angle and are located parallel to the intermediate rafters. When the necessary calculation of their quantity is made, first of all, the area of ​​the entire roof is taken into account. At one end the short rafter legs are connected to the corner rafter, and at the other they rest on outer wall building.

The central rafters are installed with the upper end on the ridge beam, and the lower end rests on the load-bearing walls of the house. As a rule, their calculation is as follows: three on one side of the roof and the same number on the other, but when designing rafter systems for large houses, an increase in their number is allowed.

Central rafters of hip roof

Intermediate rafters are elements, one side mounted on the ridge, and the other resting on the mauerlat. They are usually not used on hip slopes, since the entire area is covered by short rafters. The calculation of the cross-section and number of intermediate elements is made based on the load-bearing capacity of the rafter structure and the type of roofing material.

If the building is large, it will be necessary to install additional reinforcing elements in the form of struts and vertical posts supporting the ridge beam, and truss structures to prevent sagging of the diagonal rafters.

3 Types of hip roofs

Rafter systems in these types of roofs are made in various options. For example, if hip slope does not reach the ridge, as a result of which a vertical small pediment of a triangular shape is formed at the top, then such a roof is called Dutch.

Dutch hip roof

Hip roofs also stand out. They have all four slopes of the same shape, and there are simply no side gables in such structures. The hips in this version are triangular surfaces, the slope of which is made at the same angle as the other slopes. As a rule, such systems are used for buildings with a square-shaped area in the projection. In the group of hip roofs there are half-hip roofs mansard roofs, hipped, gable, multi-gable and gable.

Hip roof

In addition, there are broken roofs consisting of slopes of various sizes, the angle of inclination of which is different. Such structures are very complex in design, and it is also difficult to calculate them. Therefore, they are not found often, but it should be noted that they have a very attractive appearance. You can evaluate the effectiveness of roofs with a broken rafter system structure in the video, which also describes the features of their construction.

4 Calculation of hip structures - angle of inclination

The construction of hip rafter systems begins with the development of their design. A correct and competent project will allow you to assemble the roof in a short time. Optimal choice The angle of inclination of the slopes is determined depending on climatic conditions:

• In a region where windy weather prevails, the angle of inclination should be smaller, this will reduce the wind load on the roof.
• In snowier winters, on the contrary, the angle of inclination of the slopes is increased so that ice and snow do not accumulate on the roof.

Hip rafter system project

When choosing the angle of inclination of the rafters, the required amount of material is calculated accordingly. And if for lathing in almost all cases the calculation is made based on the total roof area, then the number and cross-section of corner and short rafters are calculated separately, depending on the selected type of roof.

In addition to the climatic features of the region, when choosing the angle of inclination, the type of roofing material is taken into account:

• If typesetting material is used, for example, slate or metal tiles, then in order not to increase the load on the rafters, it is better to make the angle at least 22°.
• When using roll coverings, the number of layers is taken into account. The more there are, the less the slope of the slopes can be made.
• The device of a larger angle of inclination of the slopes allows the use of roofing material - corrugated sheeting, but the height of the profile is taken into account. The angle of inclination can vary from 20 to 45 degrees.

Choosing a roof angle based on material

Correct calculation of the roof slope angle begins with determining the end axis of the building on the top frame. After this, it is necessary to mark the middle of the ridge beam; at this point the central rafter leg will be located. Then it is necessary to determine the location of the next intermediate rafter, for which the distance corresponding to the calculation of the distribution of intermediate rafter legs is measured. In most cases it does not exceed 70–90 cm.

The length of the rafters is determined so that their lower end protrudes 40–50 cm above the outer wall, and the upper end rests against the ridge beam.

A similar calculation is carried out on all four sides of the roof to calculate the location of the intermediate rafter legs on the ridge beam. Example of them correct location shown in the photo.

5 Assembling the rafter system

When designing hip roofs, you can use two types of rafters - hanging and layered. The hanging ones rest only on the walls of the building, transferring all the thrust loads to the mauerlat. If you plan to install an attic, then you will additionally need to install metal or wood ties, which are laid on the load-bearing walls of the building and subsequently serve as the basis for the ceiling. The photo shows how mansard hip roofs with a hanging rafter system are installed.

Mansard hip roof with hanging rafter system

Layered rafters are used if they have support in the form of columns or internal load-bearing walls. When designing the system, alternating two types of rafters is allowed. Where the internal walls act as supports, they are mounted on layers, and in other places they are hanging.

Fastening of rafters is mainly carried out by installing cuts (saddles). But their depth cannot exceed a quarter of the width of the rafter board. In order for the cut to be the same on all legs, it is necessary to make a template. In addition, the elements of the rafter system are fastened using metal corners, self-tapping screws, and nails. Fastening can also be done with brackets, bolts and studs.

Fastening elements of the hip roof rafter system

When installing the Mauerlat, do not forget to lay a layer of waterproofing along the top of the walls. If the walls are made of brick, then in the last rows of the masonry, embedded parts are installed for further fastening the mauerlat. Such fasteners can be made in the form of vertical studs or bolts, installed in increments of no more than one and a half meters.

Hip roofs are complex structures, but this in no way reduces their popularity. Despite the complexity of construction, they make it possible to arrange additional living space in the attic space, and if carried out high-quality insulation attic, then you can use it in winter.

Almost everything country houses, built in European style, are decorated with hip roofs. Such structures are distinguished by their reliability and aesthetic appearance. If you look closely, their structure is similar to the upper parts of houses that have been built in Japan and China since ancient times.

1 Simple and complex types of hip roofs

The simplest hip roof is a hip roof system, where the front slopes are in the shape of trapezoids, and the end slopes are made in the form of triangles. Triangle slopes are called “hips”; they originate at the end cornice and extend to the edges of the ridge. During the construction of such a structure, a system of layered and sloped rafters is used - techniques are borrowed from the schemes according to which gable and hipped roofs are erected.

The design of a half-hip roof is formed from two elements of a conventional gable roof and two hips. The cornices of the latter, as a rule, are located much higher than the front ones. Distinctive feature This type of structure is the absence of sharp protrusions. Such roofs have become widespread in regions with strong winds. If the house is being built in an area characterized by heavy snowfalls, then the slopes of the half-hip structure are made steeper. Gentle slopes of roofs – best option for less snowy regions.

The hipped system is an example of the simplest hip roof

A hip roof can resemble a tent or a pyramid, in which case it is called hipped or, accordingly, pyramidal. Similar roof structures are built on houses whose load-bearing walls form a square or regular rectangle. All sides of the hip roof are shaped like triangles, the tops of which meet at one point.

The most complex hip structure has a broken shape. This luxurious roof consists of slopes of different sizes and shapes, and each of them has a kink. A simple example of a broken roof is a gable roof, in which the front sides have a break in the upper part. This approach allows you to significantly increase the attic space in which an attic is usually equipped.

2 Six main parts of the rafter system

The reliability and longevity of a hip roof are ensured by certain components and elements of the truss structure. Installation of neither simple nor complex roofs hip type.

1. 1. Ribs (corner, diagonal rafters) - form the junction of the hips and trapezoid slopes. They are mounted at a smaller angle than intermediate rafters. A 50x150 mm board is used as a material for the manufacture of corner and intermediate rafters.
2. 2. Short rafters (springs) - one side rests against the corner rafters, the other rests on the mauerlat. The slope of the rafters is the same as that of the intermediate rafters.
3. 3. Ridge (upper horizontal rib of the roof) - absent in a hip hip structure. In roofs with complex configurations, the number of ridges can be increased to two or more. In cross-section, the ridge should have the same size as the rafter legs.
4. 4. Central rafters (ordinary) - three ordinary rafters are joined on both sides of the ridge beam. The lower part of each rests on the Mauerlat.
5. 5. Intermediate rafter legs - the upper part of the elements rests against the ridge beam, the lower part against the base.
6. 6. Mauerlat - fixed around the perimeter of the building, serves as a support for the rafter system.

The support for the rafter system along the entire perimeter is the Mauerlat

In order for the outer part of the rafter frame described in the paragraphs to acquire the necessary strength, other important elements are used in the design. For example, the stability of the ridge, in addition to the rafter elements, is provided by the racks. These supporting parts are mounted on a bench; they gain stability due to struts, which also prevent the rafters from deflecting. If it is planned to arrange an attic floor in the attic, then the racks can be replaced with other supporting parts.

Cornice overhangs can extend the life of a building. Elongated roof overhangs protect the walls and base of the house from getting wet, which is caused by slanting rains. In summer, the eaves ledge does not allow the sun's rays to penetrate into the house. But in order to increase it, parts called fillies are mounted to the rafter legs.

The hip roof structure becomes resistant to wind loads due to the presence of a wind beam in the rafter system. This element reliably connects the rafters of the roof slopes. The boards are fastened at an angle, from the ridge beam to the mauerlat, from inside the attic space. To relieve the load from the walls, parts such as trusses are used in the structure; they are mounted to the base at the corners of the building.

3 The procedure for erecting a hip four-slope

The construction of a hip roof begins with the installation of a mauerlat, which is mounted on load-bearing walls around the perimeter of the building, and the installation of a beam. If a house is built from wood, then the top crown of the frame usually serves as the foundation. For concrete and brick buildings, the Mauerlat can be made of reinforced concrete or wooden beams, it all depends on the budget and the load-bearing capacity of the walls of the house.

The bench and mauerlat are made from timber with a section of 100x150, 150x150 mm.

The timber is fixed using anchor pins; they are embedded in the masonry at the stage of wall construction. The bench is installed along the floor beams or on the internal load-bearing partition of the house; it is necessary for installing support posts. The correct installation of supports is controlled by a building level or plumb line. The supporting elements are temporarily fixed with the help of supports and self-tapping screws; they are fixed on the bed using metal plates and a corner. The racks are mounted in one row directly under the ridge beam with a distance from each other of no more than two meters.

If a hip roof-tent is being erected, then the supports are mounted in such a way that they can form a rectangle that follows the shape of the perimeter of the building. To do this, they are installed at the same distance from the corners of the house. As for the height of the supporting elements, it is determined by the roof design. If in standard four-slope system If one ridge is installed, then several purlins are installed in the tent structure on top of the supports, which form a rectangle.

As mentioned above, a simple hip roof is erected using layered rafters, which are used in gable structures. The process follows the following scheme:

1. 1. We make a template from the board, applying it alternately to the ridge and the mauerlat, mark the cuts on it from the bottom and top and cut them out. We check the finished template again by attaching it to the ridge at the place where the side rafters are installed, and if necessary, adjust the element in place. If the template fits, then we make it according to it. required amount rafters Then we mount it to the ridge and base (distance 0.5-1.5 m) using metal brackets or corners and self-tapping screws.
2. 2. At the next stage, we make corner rafter elements using a template, but since they will experience increased load, in order to strengthen them, we make them from two identical boards by splicing them in thickness. We make cuts in the corner elements at an angle of 45 degrees. We mount the upper part of the rib on the support post of the ridge, and fix the lower part on the corner of the mauerlat.
3. 3. In the gap between the corner rafters on the hip roof, we install flanges. We don’t particularly choose the thickness of the board for them, since these elements will not bear a significant load. We make the first half of the items according to the template with a notch in the upper part, the second half of the products are made in a mirror image. We mark the lower part of the extensions during installation; upon completion, we cut off the edges that form the overhang and align them using a stretched cord.

The basis for the mauerlat is usually the upper crown of the log house

Below, under the corner rafters, be sure to place supports (sprengels), since it is their lower part that will bear the largest load. The springs are mounted like support posts on a reinforced base. In order to strengthen the side rafters, struts are installed under them, the upper part of which should rest against the rafter leg, and the lower part against the leg.

4 How to properly splice rafters along the length

If a hip roof of complex configuration is being built, then due to the lack of boards of a suitable size, roofers have to splice the rafters along the length. Of course, on the basis of building materials, you can select the necessary timber, but experienced builders know that at the same time the thickness of the board increases with the length, while as a result of splicing rafters, it is possible to achieve the required length of building elements without violating the ratio of geometric dimensions.

So that the elongated parts can provide the required degree rigidity of the rafter system, it is necessary to determine what loads act on different areas of the structure. Joints can only be located in places with minimal bending moment. Usually this place is the area near the ridge. Experienced roofers are familiar with several methods of lengthening rafters, because it is impossible to use any one method in construction practice. The reason for this is the following factors:

• rafter installation step;
• limited supply of materials;
• those. construction site equipment.

The most common method of extending a rafter leg is called butt extension. We cut the elements to be spliced ​​at an angle of 900. The cut must be precise, which will prevent the formation of deflection at the joint. We fix the rafters using wood or metal overlays and nails, which we drive in in a checkerboard pattern to avoid cracking of the wood.

“Oblique cut” - we perform this method of joining elements by cutting the edges of the rafters at the joint at an angle of 450. As fasteners we use bolts with a diameter of 12 to 14 mm, which we mount in the center of the joint. If there is no time to trim the material, then we connect the rafter elements simply and quickly using the “overlapping” method, and the overlap can be up to 1000 mm. We drive nails into the beams along the entire length of the overlap in a checkerboard pattern; bolts can also be used to splice them; we screw them into pre-drilled holes. The latter method is called more reliable.

The hipped hip roof provides the house with a presentable appearance. By including mansard and dormer windows manages to revive and diversify designs. The main thing is that the calculation of the rafter system is carried out accurately, then the house will last for many decades.

The most important structure of a house, influencing the entire structure as a whole, is its roof. The main design features of the roof depend on many factors, such as the maximum permissible load on the walls, the type of construction, the type of roofing material, etc. The hip roof, the rafter system of which is not entirely simple, is nevertheless a fairly popular construction design. Its main advantage is considered to be excellent self-cleaning ability, as well as good resistance to heavy snow and wind loads.

Hip roof - design features

The hip roof has found wide application in construction due to its strong design features, durability and sufficient original design, having a beautiful appearance. The roof design allows for a spacious residential attic floor with magnificent recessed windows, and the streamlined shape reduces aerodynamic loads from strong winds.

The hip roof rafter system consists of four slopes: two of which are lateral(having the shape of a trapezoid), and two more - hip(in the form of triangles). Thus, the structure has two peaks, united by a ridge girder.

The main components of a hip roof

• Ridge run- the main load-bearing axis at the top of the roof, which is the junction of all four slopes. Executed from edged boards 50x200 mm.
• Diagonal (sloping rafters)- an important load-bearing element of the frame, connecting the corners of the house with the ridge girder. It is made from the same board as the ridge run.
• Side roof rafters- made from boards 50x200 mm. Attached to the ridge girder and side walls of the building or to the Mauerlat. Their main task is to evenly distribute the lateral load on load-bearing walls.
• Shortened rafters (springs)- a board sawn at a certain angle, which is attached to the diagonal rafters and the hip part of the wall of the house or mauerlat. Thus, there is no connection between the runners and the horse run.

Hip roof diagram

It is important to follow the basic rules for connecting structural units; the reliability and strength of the entire structure will depend on the quality of their fastening. To do this, use only high-quality lumber and rough nails.

Hip roof rafter system - connection diagram of the main components of the structure

Types of hip roofs

There are quite a lot of options for the design of hip roofs; in addition to the standard one, there are also: (half-hipped Dutch and Danish, hipped, as well as sloping roofs).

• If, for example, the length of the hip roof slope is less than the side ones, this design is called half-hip (Dutch). This design withstands strong abrasion loads with dignity, and thanks to the sharp slopes, snow almost never lingers on it for long. This type is more similar to the classic gable roof, but its characteristics are significantly superior to it.

Half hip roof (Dutch)

• The Danish half-hip roof is a little more complex in design. The difference in the design is that the hip part is no longer located at the bottom, but at the top is a vertical pediment, which can be replaced with a beautiful frame with glass.

Danish half hip roof

• Ideally suited for buildings with walls of equal length (square) hip roof. Unlike the hip roof, which has a ridge girder, the hip roof does not have one. The design looks like this: four absolutely identical roof slopes converge at one upper point. thereby forming a pyramidal geometric figure.

Example of a house with a hip roof

• Broken roofs are very rare due to the complexity of their design. However, their appearance is so mesmerizing that you cannot take your eyes off her for a long time. It is a set of many slopes arranged at different angles relative to the walls. It is very problematic to make such a roof with your own hands, without sufficient experience behind you, so it is better to entrust this matter to professional roofers.

DIY hip roof rafter system

Correct calculations are the key to the reliability and durability of any roof. Having drawn the design diagram correctly, you can easily assemble it yourself, while having 2-3 partners as an apprentice. There will be no need to resort to the help of a team of builders; it is enough to do everything according to the plan and adhere to the given calculations.

Hip roof angle

When designing any roof, its angle of inclination is chosen based on climatic conditions, which in Russia differ greatly, depending on the region. If the structure is being built in a region with heavy snow precipitation prevailing in winter, then it is advisable to make the angle of inclination large, so the snow will not be able to linger on the roof and will constantly slide off it under its own weight.

In the southern regions, where precipitation is quite rare, and only in the form of rain, but strong gusts of wind are not uncommon, roofs are erected with a slight slope. The main task of which is to resist these wind loads.

Map of wind loads of Russian regions

Another important factor when calculating the slope is the type roofing. The fact is that some of them have a recommended limit on the height of the corner, which should not be neglected. And so as not to make mistakes, read each of them:

• Slate - recommended slope angle 15º - 65°. Failure to comply with these parameters may result in moisture getting between the sheet joints;
• Ceramic tiles - the best slope angle for slopes 35° - 65°. Neglecting the slope recommended by the manufacturer will lead to the possibility of condensation;

• Metal tiles - minimum slope for this material is 13°, the maximum is not set by manufacturers;
• Soft tiles - optimal size the slope is considered no less 15º. The roof can be installed at any other angle value above the minimum;
• Ondulin - any slope angle no less 5°, the pitch of the sheathing will directly depend on the size of the angle.
• Metal seam roofing - should be used when slopes slope above 25° degrees.

Correct calculation of hip roof area

In order to correctly calculate the total surface area of ​​a hip roof, we first need to calculate the area of ​​each slope separately, then add the resulting numbers together. As we remember, the slopes of a hip roof are the geometric shapes of two trapezoids and triangles. Remembering the school curriculum, it is easy to calculate their total area.

Calculation of hip roof area

If you are still afraid of making a mistake, the specialists from whom you will purchase roofing material can make the correct calculation, or you can use any of the online calculators that are convenient for you, of which there are plenty on the Internet.

By accurately indicating all the parameters of the future roof, they will help you calculate everything with an accuracy of up to a square meter.

Calculation of the hip roof truss system

To accurately calculate the rafter system, you must use the table below for the relationship between the length and their placement.

Based on the above table, the length of the rafter leg is equal to the product of its coefficient and projection. Using the table will help you make all the necessary calculations as accurately as possible.

The calculation itself is carried out in the following sequence:

• Using a regular lath, find the position (horizontal projection) of the intermediate rafter leg. Find your slope coefficient in the table and multiply by the coefficient presented;
• From the ridge purlin to the place where the lower part of the footing leg is attached, measure the length of the rafters;
• In the same way, multiplying the correction factor by the position (horizontal projection), we find the length of the overhang of the rafters. Or you can use the Pythagorean theorem (see Fig. 1).

• Now let's find the length of the corner rafters. It will be easier to do this visually by using the figure below.

Hip roof rafter system

Installation of hip roof rafters

• The process begins with the installation of vertical supports on which the ridge girder is laid and firmly secured. After installing them, measure the resulting horizontal line; if the result is positive, proceed to the next stage.
• Installation of diagonal (sloping rafters). The lower part of the rafter legs, at the point where the support part is cut, is connected to the strapping beam in the corner of the building. The upper ones are attached to each other and the ridge beam. Their ends must have special angular cuts, made in such a way that the connection between them is as tight as possible.
• The exposed beams are reinforced with additional vertical supports. The upper end of the support is sawn at an angle equal to the angle of inclination of the rafters. Metal plates are used to fasten supports and rafters.
• The next step is to install the side roof rafters, installation step 600 mm., this step is preferable, since most standard insulation has this width. We proceed in a similar way here. The lower part with a recess is attached to the strapping beam; metal brackets or corners can be used for fixation. The upper ends are connected above the ridge purlin using plates. To ensure that the rafter fits as tightly as possible to the ridge girder, make a small notch on it at a right angle.
• The final stage is the installation of shortened rafters (springs). The installation step is the same 600 mm. One side rests on the strapping beam, the second is connected to the diagonal (sloping rafter). Pay attention to the installation of the central sprig, which is located in the middle of the hip slope. The fact is that it will immediately adjacent to both legs of the corner rafters, so the end of its upper part should have a double bevel.

Installation of shortened rafters (springs)

Frame reinforcement

In order to give the structure greater rigidity, it must be strengthened with additional corner braces and vertical posts. The required number is calculated based on the maximum load of the rafter system. The value includes weight: roofing pie and coverings, as well as the mass of snow and wind loads.

After the hip roof rafter system has been strengthened, you can safely begin installing the sheathing. Its pitch and design depend on the type of roofing material you choose. For example, under soft tiles it should have a continuous carpet.

The hip roof type is most often used for private houses or cottages. The complex is designed in the form of a hipped roof with two trapezoidal slopes. It is based on complex elements consisting of rafters and beams. In this article we will tell you how to install a hip roof, and also analyze the structure of the rafter complex.

Elements of the rafter system can be layered or hanging. The layered rafter system is considered the most profitable. This complex is used for supporting structures or structures with a middle load-bearing wall. The hanging system is used on walls with external openings. The disadvantage of the Viyasky complex is its complexity of installation.

For information! Due to the presence of an additional supporting structure, the span area can be significantly increased. Most often, such a device is used in a hipped roof with an inclination angle of 35 degrees.

The hip roof has the following rafter system:

• racks, struts;
• trapezoidal elements of the slope;
• connoisseurs;
• trusses;
• crossbars;
• sloping elements fastened diagonally or in the direction of the corners of the opening.

The diagonal sloping element is fixed with its edge into the lower support of the entire rafter system or into the beam. This design has large linear dimensions and can withstand high power loads. Spreaders are rafter elements that are short in length. They are attached to the mowing system at one support point, and the second is fixed at the lower support point. To reduce the linear size, racks and struts are used. This connection allows the installation of a hip roof without additional spacers. It is worth noting that in the ridge element of a hip roof it is possible to use spacers to support the entire structure. Installing a horizontal level, which is used together with the lower support, will help prevent the formation of thrust:

• fixation onto a beam, which is cut into an additional beam and placed on the lower support;
• fixation on the lower beam with mandatory tying of the top crowns.

Experts do not recommend performing fixation in the lower support, because such an action significantly reduces the strength and reliability of the structure. Regardless of the chosen roof structure and rafter system, due attention should be paid to waterproofing. For example, when laying a sheet on a brick layer, the section of the roll waterproofing should be 100x150 mm, but when laying a sheet on wall openings or ceilings, its height can be 10 cm less.

For information! The rafters of a hip roof may have no ribs only if there are no struts on the roof.

Purlins serve as additional reinforcement of the entire structure. They are placed as a support at a distance of 4.5 m. The installation of the trusses is carried out taking into account the linear size of the spans, and its manufacture is made from timber or logs. Sloping rafters increase the load and turn into a truss.

The installation process of the rafter complex

The design of a rafter system for a hip roof consists of the following steps:

• Construction of a mauerlat along the entire perimeter of the walls. It is fixed using threaded rods, which are installed in the masonry and tightened firmly with nuts. At the junction points of the Mauerlat, a landing plane is found and half of the beam is cut;
• The next stage requires strict adherence to the house design drawings. If the width of the house is up to 7.5 meters, the hanging rafters are connected with a crossbar at the top. If the width of the house is less than 6 meters, the bottom tightening is performed;
• After laying the Mauerlat, the central axis is marked on the end wall, the two outer posts are fixed and placed on the floor beams, secured with temporary struts;

For information! If the roof structure is covered with panels, a central beam should be installed on top, with the lower ends of the outer posts secured. If the structure is covered with beams, the racks are mounted on them and secured with self-tapping screws.

• The ridge beam is laid on the racks, the rafter legs are marked on the Mauerlat itself and their installation is carried out. The rafters are fastened to the mauerlat using the cutting method. To do this, a special cutout is made on the rafter leg, due to which the supporting elements become dense and provide high strength;
• Sloping and diagonal hip rafters are fixed to the Mauerlat, and the other end to the joining point of the ridge beam. The photo clearly shows the element of supported rafters on a hip roof.

Methods of fastening the sprig

Narozhniki are made from solid material. To ensure rigid fastening, the upper edge of this element is filed in the same area as the slanted rafters. The installation of the rafters is further reinforced with metal parts. The frames are mounted on the roof's load-bearing frame, due to which the rafters are supported, which significantly increases the reliability and safety of the roof. To increase the load-bearing capacity of the rafter system, the following method is used:

• All sides of the lower plane of the rafter element are reinforced with bars with a cross-section of 50x50 mm. The rafters should be installed from well-dried wood, pre-treated with special antiseptics.
• If the rafters are installed on the mauerlat, they are lengthened by additional elements - fillies, which serve as a canopy over the wall.

Strengthening the rafter system

When constructing rafter elements, you should take the docking joints seriously. The load-bearing capacity of the hip can be increased by installing a special rack, the task of which is to connect the slings and the floors. Another important point is the installation of the sheathing, which is made of boards or timber. Any sheathing step can be used, however, when using soft tiles experts recommend installing a continuous sheathing, and in other types the step is 20-50 cm. Comfortable stay will provide in the house competent device vapor barriers, waterproofing, ventilation and sound insulation. All building materials are laid in the form of a roofing pie.

For information! The installation of a roofing pie will ensure normal ventilation of the room and will also preserve the elements of the rafter system.

Installation of a hip rafter system is a rather complex and lengthy process that requires strict adherence to rules and regulations. Each action in its design affects not only the appearance of the roof, but is also responsible for the technical and operational characteristics. Proper calculation of all indicators and the correct structure of the roof will create comfortable living conditions in the house.

Designs with hanging rafters are in demand when constructing a roof supported only by the outer walls of the house. This construction principle is applicable to both gable and hip roofs.

Design features of a hip roof

The calculation and construction of a hip roof is much more complicated than the construction of single-pitched and double-pitched structures. A hip roof has two trapezoidal slopes and two triangular slopes (hip). This configuration allows you to withstand high wind loads and reliably protect building structures from external influences. In addition, the resulting spacious attic room can be used as a residential building (windows for natural lighting are mounted on the roof slopes).

A hip roof with a ridge girder can be erected in two ways: with layered or hanging rafters. The use of layered roofs makes the roof lighter and simplifies calculations and installation. But in this case, it is required that the building have a load-bearing middle wall. Hanging rafters during the construction of a hip roof can be used when the building is small and there is no interior walls. The operational load is transferred to the external walls of the building.

The angle of inclination of the slopes of a hipped roof with hanging rafters should be more than 40°.

The hanging rafters of a hip-type roof rest either on floor beams or on a mauerlat. Designing a rafter system requires accurate calculations and drawing up detailed drawings indicating the principles of installation of fastening units. For small buildings of the correct geometric shape, calculations can be performed independently; in other cases, it is recommended to turn to professionals, since design errors will cause a significant decrease in the reliability of the roof during operation.

At the first stage of calculations, it is necessary to select the angle of inclination of the hip roof, which directly affects its height. For a system with hanging rafters optimal angle tilt is 40 – 60°. The higher the ridge is located, the more material will be required to build the roof. Wherein high roof – the best option for regions characterized by high rainfall. A flatter roof has less windage and better withstands wind loads.

When choosing the angle of inclination of a hip roof, it is recommended to adhere to the “golden mean” rule and proceed from aesthetic considerations. You can select the angle of inclination of the slopes, and based on this, calculate the height of the ridge. Or vice versa, determine the desired height of the roof, and then calculate its angle of inclination.

When calculating a hip roof, it is necessary to ensure the correct positioning of the ridge girder. It should be located strictly parallel to the load-bearing side walls, exactly along the central axis of the building and equidistant from the end walls. Otherwise, the center of gravity of the roof will be shifted, which will lead to uneven distribution of the load on the truss structure and load-bearing walls, which can lead to deformation and destruction of the roof.

Drawings prepared as part of the project development must contain information about the location, cross-section, shape and dimensions of all elements of the rafter system. Their appearance and design features, fastening features, span width, ridge length, roof height are taken into account.

Rafter system of a hipped roof

The main elements of the hip roof truss system include::

• Mauerlat/floor beams (support for rafter legs);
• ridge girder (an element that, together with slanted rafters, determines the configuration of the roof);
• ordinary side rafters (connecting the ridge and load-bearing walls);
• diagonal (corner, slant) rafters (directed from the corners of the walls to the ridge);
• central rafter hip;
• sprigs (short rafter legs connecting the slanted rafters to the mauerlat);
• struts and racks (used as additional supports);
• crossbars (provide a rigid connection between the rafter legs in pairs);
• sprengel (serves as an additional support for the diagonal rafters).

When constructing a hip roof using hanging rafters, a ridge girder is not installed. Instead, central trusses are installed - rafter legs connected by crossbars for rigidity. The rafter system in the central part of the future hip roof is performed in exactly the same way as during the construction of a gable roof. It is recommended to make roof trusses on the ground according to a pre-prepared template in order to accurately comply with all dimensions. When installing trusses, it is necessary to check the verticality of each structure. It is important that the outermost trusses are at the same distance from the corresponding end walls of the building: this will ensure the correct geometry and symmetry of the hips.

After installing a row of trusses, bars or boards are installed in the ridge part of the resulting system (on both slopes) connecting the trusses to each other. Then, slanted rafters are attached to the outer trusses, resting on the corners of the building. At the next stage, the central hip rafter (on each triangular slope) and the flanges are installed.

Rafter trusses can rest on the mauerlat or floor beams. When developing a project, it should be taken into account that in the second case, the spacing of the beams must correspond to the spacing of the rafters. If the rafter system provides for the installation of trusses on the Mauerlat, then the tie rods located at the bottom of the trusses will not only ensure the rigidity of the structure, but can also serve as floor beams.

Bottom tightening can be used if the span does not exceed 6 meters. If hanging rafters are installed in a span of 6 to 7.5 meters, it is necessary to use crossbars in the upper part. With a span length of 7.5 - 9 meters, the upper part of the rafters should be tied to the tie using a headstock (stand). If the span length is from 9 to 10 meters, the previous type of structure should be reinforced with struts.

Before proceeding with the installation of the rafter system, it is necessary to check the geometry of the walls of the building. Top part walls (mauerlat, floor beams) must be positioned strictly horizontally.

Principles of manufacturing and installation of slanted rafters

Installing diagonal rafters is a key stage in the construction of a hip roof. It is important to ensure the correct geometry of the structure so that the rafter system evenly distributes the operational loads of the roof.

Diagonal rafters are longer than the side ones; they rest on the corners of the building frame, and in the upper part they are connected to the ridge element of the roof. The rafter half-legs (shortened) - the trusses, in turn, rest on the mowing ones. Increased strength requirements are imposed on slanted rafters, since they carry an increased load, acting as supporting elements of the system. The total load on diagonal rafters is twice as much as on conventional rafter legs. The lower part of the slanted rafters rests on the mauerlat or on a beam laid at the corner of the wall, or rests on them, depending on the design principle - spacer or non-spacer.

Sloping rafters can be made from durable laminated timber of the required length. But, most often, double boards are used, spliced ​​in compliance with certain requirements. Splicing the diagonal rafter leg allows:

• increase the resistance of the element to loads due to the doubled cross-section;
• make a continuous beam of the required length;
• unify the dimensions of the hip roof parts.

Unification allows you to use the same material for the manufacture of diagonal elements as for standard rafter legs - the use of boards of the same standard size simplifies Constructive decisions when designing and installing rafter system components.

One or two supports are installed under the diagonal rafter. The boards are spliced ​​along their length so that the joints are located at a distance of 0.15L from the center of the support. Accordingly, the length of the boards for making slanted rafters is selected depending on the length of the span and the number of supports required. In particular, if a hip roof requires a 10 meter long diagonal rafter, it is recommended to use 7 and 3 meter long boards to position the post 1/4 of the span from the top end of the rafter. In this case, the structure will be able to withstand the design loads - it is not recommended to place supports under the middle part of the rafters.

A strut or stand made of timber or paired boards acts as a support for the diagonal rafter. The installation angle is not of fundamental importance if the strut rests against a solid reinforced concrete floor(with laying a waterproofing layer). If the stand rests on the bench, the installation angle is usually 35 - 45° to the horizontal plane.

Additional supports are installed according to the following principle. Span lengths up to 7.5 meters require the use of one strut. If the span is 7.5-9 meters, a support is installed at the bottom of the rafters, or a truss truss is installed. As the span length increases, additional support is installed. If the ceiling is not strong enough, it is necessary to lay an additional intermediate beam to support the racks.

Sprengel is a beam that intersects the angle formed by two walls adjacent to each other. A truss truss is a structure in which the slanted rafters are supported by supports that rest on the trusses. The entire system is strengthened by two struts. To make a truss truss, timber of 100×150 mm for beams, 100×100 for racks and 50×100 for struts is used.

Installation of the upper part of the diagonal rafters

The upper end of the hanging rafters is attached to the ridge part of the outer truss when installing a system with hanging rafters. This may require the use of a sprengel or a hammer (a short board with a thickness of 50 mm), to which the ends of the diagonal rafters, sawn at the required angle, are attached. If the ridge is positioned with an indentation from the ridge, you get a Danish half-hip hipped roof. The following types of fasteners can be used to secure sloping rafters at the top::

The frames are attached to the slanted rafters using the cutting method or with the installation of cranial bars (the second option makes it possible to obtain a more rigid structure). The cross-section of the bars, which are sewn onto the rafters on both sides, is 50x50 mm. The frames should be supported on the rafters with a shift so that joints of the bars do not form at one point.

Hip roof with hanging rafters, hip roof rafter system

Hip roof rafter system: specifics of the device and description of the installation process

Hip roofs offer an impressive list of compelling benefits. These include an impressive shape, uniform heating and reliable protection houses from precipitation. Due to the absence of gables, hip structures are not subject to significant wind loads. Compared with gable options there is much less reason to fear deformation. The list of advantages can be continued, but their flow is slowed down by a very compelling circumstance: the rafter system of the hip roof is not pleased with the simplicity of the device. However, complexity will not stop an independent builder if he is familiar with the nuances of constructing a hipped frame.

Characteristic features of hip roofs

Hip roofs differ from their gable counterparts in that there are no vertical gable walls in their design. The place of the pediments was taken by triangular slopes located at the ends, significantly reducing the real and visual volume of the roof. The economic effect of reducing volume is a controversial issue. When cutting large-sheet material into hip slopes, costs, on the contrary, increase. For example, laying corrugated sheets or installing metal tiles will force you to fork out for the purchase of a coating one and a half times more than for the installation of a standard pitched structure. Purchasing piece materials will allow you to reduce the construction budget, because you won’t have to spend money on cladding the ends of the roof.

By analogy with any building structure, a hip roof can be divided into simple geometric shapes. In the simplest version, without mates and valleys, it has two pairs of symmetrical slopes: two triangles and two trapezoids. On this basis, the hip roof received the parallel name “hippable”.

Viewed from the front, its cut resembles an ordinary triangular gable roof. In profile, the structure has a trapezoidal configuration, which can also be divided into a rectangle with two mirror-image triangles on the sides. The shape of the trapezoid depends on the architectural preferences of the owner. It is determined by the ratio of the length of the eaves overhang to the length of the ridge. The part of the structure, limited by a rectangle, is constructed in accordance with hanging or layered roofing technology standards.

The hips that replaced the gables are installed at a certain angle to the horizon, because they must adjoin the inclined sides of the trapezoid. It is in their design that the main problem with the hip rafter system lies, because it will not be possible to install it using the usual pitched method. After all, the ridge run does not completely cover the slope. Therefore, the rafter legs of the hips and the triangular parts of the large slopes associated with them literally have nothing to rest their upper heels on.

The support for them will be special slanted rafter legs connecting the ridge girder with the corners of the structure. If you look at the hip rafter structure from above, the slanted rafters will look like diagonals. The installation direction was the reason for receiving the second technological name - “diagonal”. Naturally, rafter legs of different lengths will rest on the diagonals, because They are installed perpendicular to the roof overhangs. They have their own name - narozhniki.

Summarizing the information, we get that the construction of a rafter frame for a hip roof will involve:

• Ordinary rafter legs, resting with the lower part on the mauerlat or on the floor beams. Depending on the type of support, they can be hanging or layered.
• Diagonal rafters connecting the corners of the roof and the edges of the ridge girder. Note that they are used not only in the construction of convex corners of hip roofs, but also in the construction of concave corners of valleys.
• Narozhniki, forming the planes of the hips and parts of large slopes adjacent to the slanted rafters.

Installation of hanging and layered rafter legs is carried out according to the rules according to which the rafter system is constructed gable roof. We will deal with their diagonal brothers and with the rafter half-legs.

Diagonal rafter legs

Taking into account the diagonal arrangement, it is easy to guess that the length of the slopes is longer than the length of ordinary rafter legs. In addition, they serve as supports for narodniks. As a result, sloped rafters are loaded one and a half times more than ordinary analogues. Therefore, it is customary to make them paired from two boards with a cross-section equal to the same size of material for ordinary rafter legs.

Pairing sloping rafters simultaneously solves three technical problems:

• Allows you to increase the load without risk due to the double cross-section of the load-bearing element.
• Provides the opportunity to obtain a diagonal structural element of any length without areas weakened by extension.
• Eliminates the need for targeted purchase of timber for sloped rafters.

Due to their length, diagonal rafters require additional supports, the number of which depends on the length of the rafter leg.

Supports for diagonal rafters

Regardless of the scale of construction, any scheme for a hip roof rafter system includes supports to strengthen the diagonal rafter legs. If the design size of the slope is more than 9 m, i.e. it covers a span of equal meters, its stability is ensured by two additional supports. For smaller spans, one support located in the upper span zone is sufficient.

The following can be used to support a diagonal rafter:

• Rack, installed vertically directly on the ceiling. A piece of waterproofing is laid between it and the ceiling if the rack is to rest against a reinforced concrete slab.
• Strut. It is installed, as befits braced rafters, at an angle, the size of which can vary from 45º to 53º. The magnitude of the slope is not particularly important. It is important that the strut itself supports the rafters in the most loaded area. The lower heel of the strut is rested on the bed.
• Sprengel. It is a T-shaped short beam made of timber, turned upside down. Used in the construction of large spans that require two or more reinforcing supports. The sprengel is installed so that its base is perpendicular to the rafter. It is located at the bottom of a large span closer to the corner of the roof. Instead of a truss, a regular short stand can be used.

Additional supports are made, again from a double board or block, and installed at the most loaded points.

The video review will introduce you to the nuances of installing supports for a hip roof frame:

The nuances of supporting rafters

The upper heel of the diagonal rafter rests on the ridge purlin different ways. The choice of method depends on design features rafter system:

• In rafter structures with one purlin along the central axis of the roof, the diagonal rafter legs rest directly on the purlin consoles.
• In rafter systems with two purlins and plank rafter legs, the diagonal rafters rest on a truss, which in turn rests on both purlins.
• In rafter frames with two purlins and rafters made of timber, in addition to the sprengel, a sprengel is used - a short piece of board that sews together ordinary rafter legs in the ridge area. The thickness of the reinforcing short is 5 cm or more.

The heel of the diagonal rafters for landing on one of the listed upper stops is trimmed in fact. Fastening is done with nails. If necessary, you can strengthen the fixation with wire twists or metal clamps.

The lower heels of the slopes can be rested against the corner of the mauerlat or a specially installed corner beam. You can simply lean on them. The diagonal rafter legs are fastened with metal brackets, nails on top of a wooden overlay, or corners.

Narozhniki and methods of their construction

Narozhniki form the hips and triangular parts of large slopes. The top of the half-leg rests on a slanted rafter, the lower heel on a mauerlat, a mortise beam or a wooden floor beam.

Installation of spigots can be carried out:

• By cutting. In slopes, nests are chosen so that the half-legs of adjacent slopes are not located opposite each other. It is recommended that the distance between cuts be at least 20cm. Therefore, during the installation step, the setters are allowed to move so as not to cut out the nests at one point.
• By installing cranial bars, serving as supports for the half-legs. 50x50mm bars are built up along the lower edges on both sides of the diagonal rafter. Their presence makes it possible to avoid cuts that significantly weaken the load-bearing element.

The second option is easier to work with and is preferable due to the increased rigidity of the structure. In addition, it absolutely does not oblige you to change the installation pitch of the half-rafters: they can be located opposite each other. The frames are attached to the mauerlat or beams using the same method as was used to install ordinary rafters.

Elementary hip rafter system

The easiest way to crown a country property hipped design consists of purchasing and installing ready-made roof trusses. However, it is much more interesting, useful, and cheaper to construct a hip roof and a rafter system that matches it with your own hands. Moreover, if it is planned to be erected over a small outbuilding, gazebo or summer kitchen. On simple designs It is very worth practicing before applying efforts to more important objects.

Note that in the example below there is no ceiling, the attic is not enclosed and there is no insulation. Snow practically does not linger on the slopes, i.e. the slanted rafter legs are subject to a minimum load by their standard standards. The principle of dispersal between drug addicts has not been preserved. All nodal connections are made with nails and metal corners. The performer will need a 5x25cm board for making rafter legs and purlins, as well as moisture resistant plywood for the construction of a continuous sheathing, because the building is planned to be covered with bitumen shingles.

Stage 1: Modeling and Design

Regardless of the architectural complexity of a building structure, it needs a design. It will help you decide on the optimal shape and save you from buying unnecessary materials. A simple hip roof with a standard rafter system will not require super complex drawings, but it is necessary to make at least a simple sketch.

Instructions for simplified design:

• We measure the width/height/length of the building. According to the data, we draw the profile and full face of the building on a sheet of paper on a scale, for example 1:50. This means that all sizes will need to be divided by 50. That is. a wall of a house with dimensions of 5x2.5m will be depicted in a homemade drawing as a rectangle with sides 10x5cm. If it looks too small, you can choose a larger scale - 1:40, 1:25, etc. It is advisable to duplicate the finished sketch a couple of times as a reserve.
• We choose the optimal roof height and the angle of its steepness. To do this, on one of the duplicates of the sketch, we draw several options for the outline of the roof. We determine the most successful one and measure the angle of inclination of future slopes with a protractor.
• We mark the installation points of the layered rafters on the double sketch; this is a step. We need to divide both walls into equal sections. It is not necessary that the installation pitch under the hip and pentagonal slopes be the same. In the example, the distance between the rafter legs on both walls of the building is 20 inches, which is 50.8 cm. In fact, the installation step can vary from 0.4 to 2.1 m. However, we note that too often installed rafters will increase the consumption of material many times over, and too rarely will force the structure to be reinforced with an additional counter-lattice.
• Let's decide on the length of the skate. Let's draw it on a duplicate of the template, taking into account that the ridge beam must connect a whole number of pairs of rafters. Let's set equal distances from both edges of the long walls.
• We transfer all the results to the main sheet and calculate how much material is needed. We calculate the length of the rafters on the outer sides, taking into account the length of the eaves overhangs of 40-50 cm. We calculate plywood consumption by the number of solid panels per plane of a hipped roof.

Based on the number of rafters, we calculate the amount of fasteners. We will need nails in literally all nodal fastenings. There should be a pair of corners for each rafter leg. Don’t forget to buy a board with a small margin in case of mistakes own work. To install a hip roof on brick and foam concrete walls, you will need a block for constructing a mauerlat. It is not needed if the rafter system is installed on wooden walls.

Stage 2: Construction of the main part of the hip roof

First of all, we will build auxiliary scaffolding on the basis that between the plane homemade stand type of high bench and ridge girder should fit House master in full height.

The start of the installation of the rafter system for the future hip roof is the installation of the ridge part of the structure:

• We nail an auxiliary board to the walls of the building adjacent to the hips, one edge of which should coincide with the central axis. We stretch a string between the boards, repeating the central axis.
• We try on a pair of rafters at the end of the building. They should intersect directly under the lace. We outline the cut lines of the upper heels according to the fact, not forgetting that there will be a 5cm thick purlin between the rafter legs.
• Using the templates obtained, we prepare layered rafters.
• We install the rafter legs in pairs according to the marks of the main part of the system. Temporarily fasten with one nail.
• We install the ridge run between the upper heels, which previously rested freely on each other.
• We nail the rafters to the purlin.
• We attach the bottom of the rafters to the mauerlat or upper crown of the house with metal corners.

We dismantle the auxiliary boards; we will no longer need them.

Stage 3: Construction of hip slopes

We fasten the hip part of the rafter system in the same way: the lower heels are attached with corners to the mauerlat or to the upper crown, the upper heels are secured with nails. We carry out the work in the following sequence:

• We try on the first rafter to the slope, marking the actual cutting line. The bottom of the rafter must pass exactly through the corner marking point.
• We saw off the marked excess. We nail the diagonal leg to the ridge console, fixing the bottom with corners.
• We do the same with the other three braids.
• We fill the hip slope with spigots, having first tried on each part in its proper place and sawed off the excess.
• We install the pentagonal ramps.

At the end of the work, the rafters are screwed one by one with wire twists to the wooden plugs embedded in the walls or to the second crown, so that the structure is not torn off by a strong gust of wind. There is a way to lay strands of annealed wire into the masonry during the construction process for subsequent fixation of the rafter system. There should be three more rows on top of the twisted wire brickwork or two rows of foam blocks.

The sheathing is laid over the finished rafter system. In case of use soft roof, as in the above case, the sheathing is made of solid sheet metal, plywood or similar boards as a covering. A gap of 3 mm is left between the slabs or boards. For hard materials, the sheathing is constructed from a bar with the step recommended in the instructions.

Construction of complex hip roofs

The principle of constructing hip roof frames with more complex architecture is not much different from the example given. The sequence of work is exactly the same. True, it is still wiser and more reliable to fix layered rafter legs with the help of notches. It is highly desirable to use supports for diagonal rafters. And before installing the ridge part, support frames are installed with a beam at the bottom and a ridge purlin at the top. Another change in the angle of inclination of the slopes when supported by a notch should be taken into account at the design stage.

Hip roof rafter systems - installation instructions

What is a hip roof?

This roofing option has four slopes. Its two long inclined surfaces have a trapezoidal shape, and the other two, smaller ones, have the shape of a triangle - they are called hips. They are located along the gables of the building and connect the ridge to the cornice. Trapezoidal planes have a large area and a slope, also located from the upper horizontal edge to the cornice.

The hip roof has several different designs:

1. Traditional with two trapezoidal slopes and two hips, it is called a “Dutch” roof.
2. Tent - has triangular-shaped slopes of the same size. Ideal for square-shaped buildings.
3. Half-hip - the hips cover only the upper part of the end no more than to the middle. Suitable for the construction of houses with an attic; it is called “Scandinavian” roofing.
4. Semi-hip - the hips are not triangular in shape, but are in the shape of small trapezoids. Such a roof provides a large attic space; it is also called a “Danish” roof.

Like any other type, the hip roof type has a frame and rafter system - the entire structure rests on them.

Construction of the rafter system

The rafter system is the main component of the entire roof structure.

Unlike a gable roof, the structure of the supporting structure of a hip roof is more complex.

Regardless of whether the building is rectangular or square, the shape of the slopes will not change.

Considering the structure of the hip roof rafter system, we can determine that it consists of several elements:

1. Mauerlat is the base for the rafters, the connecting link between the load-bearing walls and the rafter system.
2. Oblique or diagonal supports - have the greatest length and carry the greatest load.
3. Central rafters - serve to connect the ridge with the Mauerlat on the sides of the slopes, converge at the corners of the ridge on 3 sides.
4. Intermediate rafters - connect the ridge and cornice.
5. Struts - create not only rigidity, but also provide confrontation to wind loads from the gables of the building, located at different angles to the rafters.
6. Narozhniki are the shortest rafters.
7. Sprengels or truss trusses - enhance the load-bearing capacity of the roof structure. They are a beam made of timber located at the corner of connecting external walls.
8. Racks – give the legs of the supports additional stability; they are installed at the junction of two rafters and a ridge beam.
9. Corner rafter (rib) - located at a smaller angle than the intermediate elements of the system.
10. Short rafter legs - fixed to a corner support board.
11. Horse.
12. Tightening - performs the function of a floor beam.
13. Wind beam - attached with a slope on the windy side of the roof.
14. Purlins - the distance between the connection of supports to the ridge.

Rafter system diagram

Installation of rafters

Once the type of roof has been determined and all the necessary building materials have been purchased, you can proceed directly to the construction of the frame.

Before starting the construction of a supporting structure, it is necessary to draw up its design and drawing.

So, the design of the support system consists of several stages:

1. Before starting construction, a wooden beam should be laid around the perimeter of the outer wall - a mauerlat. To lay it, it is necessary to equip a reinforced belt of reinforced concrete structure, which enhances the load-bearing capacity of the walls. You should pay attention to ensure that the Mauerlat is securely fastened, preventing the slightest movement.
2. If the walls are made of stone or brick, formwork is erected on top of them, into which a reinforced frame is mounted using galvanized threaded rods with a caliber of at least 10 mm. The upper part of the studs should protrude 4-5 cm from the base for the supports (mauerlat).
3. After installing the frame, fill it with cement mortar.
4. Then, as the concrete hardens, its surface is covered with bitumen and covered with a layer of roofing felt or other waterproofing materials.
5. Beams with drilled holes are placed on the protruding part of the studs. Secure the structure with nuts.
6. The Mauerlat is made from 10*15 or 15*15 cm pine needles, dried and impregnated with anti-corrosion and fire-retardant agents. The humidity of the wood should not exceed 20%.
7. The next step is to install the central beam on the mauerlat, which is located parallel to the ridge. Stands are attached to it. These posts serve as support for a specific part of the support system.

Types of hip roof rafters

Hip roof supports are divided into two types:

1. Hanging - beams are located on the beam of the ceiling of two external walls without additional support.
2. Layered - along the upper edge of the internal walls there is a horizontal beam, to which vertical supports are attached. The basis for the end part of the beam is the external walls.

The layered type of supports is suitable for buildings with an intermediate supporting wall or columns.

This supporting structure has more base points, so it can be made much easier.

If the building has two load-bearing walls, a screed is installed to support the rafter legs and distribute the load across all vertical supports.

For a hip roof type, a layered system is considered the most suitable, giving greater strength and facilitating the roof structure.

This modification is used when constructing an attic or mansard roof.

How to calculate the rafter system of a hip roof

Calculation of the supporting structure is the main stage of roof design. The slightest miscalculation can cause deformation or destruction of the roof.

After studying the roof structure, it is necessary to calculate the angle of inclination of the rafter system. The higher it is, the more the roof is exposed to winds, but it clears itself of snow and ice on its own.

The angle of inclination of the slopes can be 5-60 degrees, it depends on the load of wind and snow.

After determining the angle of inclination, calculations should begin to determine the main loads to which the roof is exposed. These include the weight of the roof itself and natural phenomena - wind and precipitation.

The total weight of the supporting structure, sheathing, covering and insulation is divided by the area of ​​all inclined planes.

The resulting value shows the load per 1 m2 of roofing. For a residential building, it must withstand a load of 45-50 kg/m2. This figure is the same for any area.

Sediment loads vary depending on the area and range from 80-150 kg/m2. This value can be found using the “Building Codes and Regulations”.

1. The load value must be multiplied by the correction factor:
2. At 1.0, when the angle of inclination does not exceed 25 degrees;

By 0.7 if the angle is 25-60 degrees.

If the roof is subject to regular heavy snowfalls, it is recommended to install double supports or continuous sheathing.

The load indicator (wind and snow) is multiplied by an index equal to the rafter pitch value. The pitch of the rafters is determined in meters.

The final stage is the calculation of the quantity and criteria of materials.

1. After calculating all the loads per 1 m2 and the area of ​​the entire roof, determine the cross-section of the supports (smallest values):
2. Mauerlat – 10*10 cm.
3. Tightenings and purlins – 5*15 cm.

Fillers, struts, crossbars – 10*10, 15*15 cm.

When carrying out calculations for large-scale projects, it is recommended to use special computer programs for design.

All obtained indicators must be plotted on the drawing.

Precisely calculated nodes make it possible to achieve strength and attractive appearance roofs.

The connection of roofing structural elements is carried out in accordance with certain requirements.

Main components of the supporting structure:

• ridge unit - a pair of supports are fastened with nails or bolts, and reinforced with bolted beams;
• the support unit for the beams on the mauerlat is reinforced with metal corners, construction staples, nails or bolts;
• rafter connection unit with a tightening, which is located in the middle of the rafter - carried out using nails or bolts;
• the combination of the strut, rack and support is done using a die cut and reinforced with construction staples.

Rafter system

The quality of the roof directly depends on the frame and base for the roof deck. The supporting structure of the roof serves as the basis and determines its service life.

Rafter system for mansard hip roof

This support system is resistant to strong wind loads due to the absence of a roof façade wall.

A roof of this form makes it possible to build large plumbs that protect the walls and foundation of the house from rain, snow and ice.

Components of the attic roof rafter system:

1. Mauerlat.
2. Ridge and side girders.
3. Support beams.
4. Layered and hanging rafters.
5. Struts.
6. Support posts.
7. Diagonal rafters.

A distinctive feature of the mansard hip roof is the use of layered and hanging rafters in its design. The upper slope is made from hanging rafters supported on racks or a side girder.

To avoid bending, they are equipped with drawstrings. When installing the lower slope, layered rafters with a base on the Mauerlat are used, and a horizontal beam connecting the rafter system in its middle part.

The lower sloping surfaces have an inclination angle of about 60 degrees, and the upper ones - at least 30 degrees.

Strengthening the rafter system

To ensure the strength and durability of a hip roof, it is not enough to manufacture a rafter system; it must also be strengthened.

The most common methods of strengthening are:

1. Installation of trusses on the corners of the roof with a stand supporting the diagonal support. If the truss is located far from the corner, it is best to attach a truss truss to it.
2. Installation of racks connected from above by a beam on the ceiling (reinforced concrete) or tightening. They act as supports and ensure even distribution of the load on the house.
3. The use of double beams instead of one beam if the diagonal rafters are too long.
4. Using wooden boards 40*40 or 50*50 mm to construct the sheathing.

Hip roof rafter systems - calculation, diagram and how it works

The hip roof rafter system is a type of hip roof.

General scheme The hip roof rafter system consists of four slopes, two of them have the shape of a triangle, the remaining two are made in the form of trapezoids.

In this case, the trapezoidal shapes are connected to each other by straight upper edges, and the resulting side openings are equipped with triangular slopes.

The advantages of using a hipped roof are aesthetic appearance and savings in consumables.

In addition, the hip roof rafter system is great solution for home improvement attic floors and a bay window.

But unlike the construction of other types of roof systems, the construction of a hip roof rafter system requires much more labor.

Types of rafters and main components of a hip roof

To design a hip roof structure, a diagonal or intermediate rafter arrangement can be used.

Also, the elements of the hip rafter system are divided according to the technology of the device into layered and hanging.

The first type of rafter structure is considered an economical and proven option. Most often, such systems are used for buildings with a support-type frame or with a load-bearing central wall.

The second rafter system is difficult to install; it is usually installed on external wall openings.

Hanging rafters are attached only to the mauerlats and to the ridge girder; they are used if the distance of opposite walls does not exceed 6.5 m.

The rafter parts are made from dry timber 150x50 mm, pre-treated with an antiseptic.

Here is a photo of the design of the hip roof rafter system.

The rafter diagram for a hip roof contains:

• slopes (placed diagonally or directed to the corners of the walls);
• trapezoid elements;
• short bars - trusses;
• slopes, support posts.

The slanting parts are attached diagonally: with one side to the lower support of the structure or to the beam extending it, and the second side is fixed to the other pair of rafter elements.

Unlike conventional systems, these roof rafter parts, given their size, are much larger.

They can take on more weight and act as a support for external rafter parts that do not reach the ridge beam.

The main parts of the hip roof system are load-bearing beams and a ridge. In turn, beams are divided into two types.

The first type of beam is made from the material used for rafters. It is located transversely and serves as a support for the posts supporting the ridge span.

Mauerlat is the second type of beam; 100x150 mm beams are used for its production. The beam is placed around the perimeter of the object.

If the building is made of wood, the upper crown will act as a mauerlat.

Calculation of rafters for a hip roof

When designing a hip roof yourself, you need to pay attention to the choice of material, as well as take into account the amount of precipitation and wind strength.

Oddly enough, but based on these facts, it is possible to correctly calculate the slope and height of the roof.

The slope angle of trapezoidal slopes can be from 50 to 60°; an example can be seen in the photo. Which figure is optimal will depend on the strength of the wind and snow load.

In case of heavy snowfalls, the angle of the slope is made large; in case of strong wind loads, the angle is made small.

Here it is necessary to clarify that the design of hip roofs becomes more complicated as the slope angle increases, and material consumption increases.

Having found out the height readings and slope angle, we will calculate the rafters using the example of a hipped roof structure with two identical shapes of trapezoids and triangles.

The calculation may have the following order:

• When the slope angle is marked as main indicator, then the height of the ridge beam is calculated as follows: (tangent of the angle) x (by the step size between the edges of the slopes) / 2. Based on the roof height indicator, the calculation is made in the opposite direction. Determine the tangent of the angle: (roof height) x 2 / (for the gap between the edges of the slopes);
• The length of the roof slope is calculated using the so-called Pythagoras. The sum of the legs of the triangle is determined and the square is calculated. Using the same principle, the dimensions of the slopes are calculated by dividing the trapezoidal roof slope into two triangles and one rectangle.

Having determined the values ​​and drawn up a drawing, a general calculation of the roof area is carried out. The total area is calculated by determining the areas of the hip and trapezoidal sides of the roof.

The area of ​​a trapezoid is equal to the sum of the values ​​of its bases divided by two and multiplied by the height.

The area of ​​a triangle is calculated as half the product of the length of the base and the height divided by two.

The roof area can be found by combining the values ​​and multiplying them by 2.

Having made such a calculation, you can determine the quantity building material for the construction of a sheathing frame and a hip roof.

Also, using this value indicator, it is possible to calculate the required number of hydro- and heat-insulating products and the number of fasteners.

Hip roof rafter installation

The construction of the rafter system begins with the installation of beams. First of all, the installation of the Mauerlat is carried out, then the transverse beam.

The ridge support posts of the rafter system are mounted vertically and fixed with self-tapping screws; to strengthen the support posts, jibs are used. The skate should be exactly in the center of the object.

The material for the ridge and rafters is the same, with parameters of 150x50 mm.

Next, four sloping elements of equal length are mounted; special attention is paid to the work process, since it is at this stage that all the planes of the slopes of the structure are laid, which must have ideal evenness.

Diagonal rafters have the longest length, which is why you have to connect several rafter boards into one.

Each of them should be attached to the ridge beam and protrude 0.5 or 1 m beyond the wall of the house.

Thus, a cornice is installed as in the photo, which subsequently protects the walls from precipitation.

As for the cross-section of the rafter material, it is selected depending on the slope of the roof, taking into account the loads of the space between the main walls and between the rafters.

Installation instructions for intermediate rafters

When arranging a rafter system for a hip roof, the following instructions must be followed:

• The intermediate and central rafters are attached to the top of the ridge beam, their second edge should protrude beyond the load-bearing walls. The required number of parts is determined taking into account the length of the house;
• When corner elements are mounted, their upper edge is arranged on slopes. As they approach the corners of the walls, their length decreases.

A correctly drawn up drawing of the future structure, where the fastening points of the central parts are precisely marked, will allow you to eliminate the occurrence of inaccuracies when arranging the rafter system of a hip roof.

The classic method involves the initial installation of central rafters - 3 parts on each side. The fastening points are located along the edges of the ridge beam.

In order to install the first rafter on the hip, mark one point in the center of the wall on the mauerlat and the center point of the thickness of the ridge beam.

Then the central part for the trapezoidal slopes is installed, and all the intermediate rafters are installed parallel to them.

Double bevel cuts are made on central and diagonal elements that will intersect during installation. It is recommended to strengthen the connections with ties.

Features of installation of spigots

Corner rafters are mounted parallel to the main ones. A cut is made on the shortened parts, then each of them is laid and secured on slopes.

Fixation is carried out using self-tapping screws or nails. They can also be connected using a timber support fixed to a diagonal element or by cutting.

It is not recommended to connect the corner elements (springs) of a hip roof, triangular and trapezoidal slopes, in one place, with diagonal elements.

If the area of ​​the house is large, then it is necessary to carry out a calculation, noting the degree of sagging of the intermediate and diagonal rafters.

The central element of the hip structure system is attached to the ridge beam using two wooden ridges.

In order to make the corners of the hip rafter system more durable, trusses (additional beams) are installed.

Their use makes it possible to support the diagonal elements of the rafters and thereby impart strength to the structure.

Lathing and insulation for a hip roof

The frame of the sheathing of the hip roof truss system is carried out in accordance with the instructions for the installation of the selected roofing material.

Installation of the sheathing can be carried out using wooden beams or boards. The cross-section of the beams should be 50x50 mm, the thickness of the boards should be at least 20 cm.

Sheathing structures can be continuous or with gaps; the spacing of their location will depend on the type and size of the roofing product.

When insulating a hip roof, three methods can be used:

• thermal insulation material is mounted between the beams of the rafter system;
• the insulation is laid directly on the rafters;
• the insulating layer is placed under the rafters.

At the moment, the most common technology is the first option. Mineral wool, liquid polystyrene foam or polyurethane foam can be used as thermal insulation.

When insulating a hip roof, it is important not to block the ventilation gap.

Depending on the chosen type of roof structure, select waterproofing material, which is mounted on the insulating layer or under it on the rafters.