What are side and hip rafters? Hip roof rafter system: design and installation

It is difficult to name a more important part of the building than the roof. It is chosen taking into account weather conditions and materials, which should ensure its durability and reliability. It goes without saying that attractiveness appearance roofing also plays an important role. With all the variety of today's choices, the unusualness of hip roofs deservedly places them in one of the first places in adding attractiveness to any private home.

What it is?

The hip roof consists of two inclined surfaces that are shaped like trapezoids, plus a pair of shorter slopes that are shaped like an inclined triangle.

The main difficulties in arranging traditional hip roofs occur at the stage of erecting rafter structures, which consist of slanted, row and outer rafters.

Hip roofs have excellent resistance to wind loads and generally have high performance characteristics.

At the design stage it is necessary to comply with:

choice optimal material for arranging the roof structure;
determining the intensity of precipitation characteristic of the construction site;
setting average and maximum wind resistance values.

Taking into account the above indicators, you can calculate the optimal value of the angle of inclination of the slopes and the heights of the roof structure.

To perform calculations and draw up a project, you can use the services of a specialist or select projects in open source. Having the proper skills, the mentioned activities are carried out independently.

Peculiarities

The roof in question is designed in a unique way. A larger slope is used on any roof, but a short one makes this design worthy of attention.

Design roofing system such that the slopes do not compensate for the vertical projection of the building in length, and the remaining free area is filled with two short hips.

If you try to draw up a diagram of a hip roof structure yourself, you need to use a marking strip and Pythagorean tables.

The support for the hip roof rafters is the so-called “mauerlat” and ridge beams.

The composition of the roofing “skeleton” is as follows:

Support base (mauerlat). It is made of timber 100x150 mm or 150x150 mm. It depends on the structural features of the house. The horizontal fastening of the Mauerlat is provided by four jibs, which give rigidity to the entire structure. The Mauerlat is made of thick timber and attached to the upper end of the wall using a pin or dowel.
Racks installed along the central axis of the floors along their long sides and reinforced with temporary supports. Subsequently, ridge beams are attached to them. Their height is chosen depending on the slope angles. Accordingly, the higher the racks, the smaller the angles between the rafter legs.
Ridge beam- these are the upper horizontal crossbars that lie on the rack and serve as supports for the rafters. Ridge beams are attached to the post; they serve as supports for the main rafters.
Main rafter It is supported on a mauerlat and a ridge beam and is secured to them with special galvanized steel plates.
Diagonal, or the sloped rafter goes from the end of the ridge beams to the corner of the buildings. The temporary post fastening is removed when all diagonal rafters are installed.
Narozhnik It is attached from below to the Mauerlat, and from above to the slanted rafters. Used as a continuation of the plane of the main slope. They have intermediate distances, just like between the rafters.

Sprengel. It goes from the Mauerlat jib to the diagonal rafters and provides reinforcement to the roof.
Strut. Needed to enhance the roof's resistance to wind. Theoretically, it is installed on the windward side (from the “wind rose”). In practice, the brace can be used from any side.
Lathing. They are carried out inside along the rafter leg and determine the base of the roofing “pie”. The designs of rafter systems include some important elements with strictly defined functions for each.

Advantages and disadvantages

Advantages:

Compared to gable roof hip resists the wind minimally. Because of all the inclined slopes, the wind does not put pressure on the pediment.
The structure has greater rigidity due to the presence of an angular rib that connects to the support beams of the skates.
There are protruding overhangs that further protect the walls.
Great aesthetic appeal.

Flaws:

complex calculations and installation;
high cost;
small attic space;
lack of attic;
sunlight enters only through special windows.

Kinds

When considering the types of hip roofs, it is necessary to take into account their varieties, the choice of which affects the design of the rafter systems.

Classic type. The diagonal ribs rest on the ridge support beams, the overhangs are located at the same height. The pediment is triangular, the slope is trapezoidal.
Tent type. The ridge support beam is missing. The diagonal rib ends at one point, and an ordinary short rafter is adjacent to the ribs. This is how roofs are built if the building in vertical projection is a square.
Half hip type. The gables are vertical; window openings are installed in them. There are two varieties of the half-hip type - Dutch and Danish.
Broken hip type(attic hipped). It represents the greatest difficulty during construction, since the slopes are of different sizes and have different angles of inclination. This type makes it possible to rationally organize the internal roof space and allows you to give the roof an unusual appearance.

There are also several other types of roofs - one-story, two-story, cuckoo, bay window, L-shaped.

How to choose?

Question of type selection hip roof depends only on the preferences of the owner, or more precisely, on the thickness of his wallet. For example, gable windows will cost no less than regular ones, and metal tiles on the veranda roof will be more expensive than other materials.

Calculation

The rafter system is calculated taking into account the following prerequisites:

Wind loads. The stronger the wind, the more positioned the slopes are, which, in turn, strengthens the entire structure.

Precipitation. The more that falls, the steeper the slopes become, avoiding the extra weight of snow/rain that collects on the roof and puts pressure on the rafters.

Type of materials from which the roof is made. This must be taken into account at the project stage.

Roof insulation. Here the distance between the rafters will depend on the width of the strip of materials with which the insulation will be produced.

The slopes of the angles of the slopes determine the laying of the rafters. Accordingly, the laying of intermediate rafters is calculated as follows:

the top trim of the end wall is marked with the center line;
then calculate the half-thickness of the ridge beam and draw a line to define the first central intermediate rafter;
then the end of the batten is aligned with the line of the marked center of the intermediate rafter;
mark the other end of the staff internal line side wall;
get a point, which will be the laying of the intermediate rafters.

The proportion of the length of the rafter and its laying is calculated using a coefficient that depends on the angles of the slopes. The lengths of the rafter legs are determined by multiplying the laying by the coefficient.

Installation stages and subtleties

When purchasing roofing material, you need to know its total footage. Usually for this she total area conditionally divided into parts in the form of simple geometric figures and make calculations for each.

In this way, it is determined in advance financial expenses for roofing material and for construction, and the need for arrangement and the exact configuration of the sheathing are determined.

As a result, a diagram of the rafters will appear.

It is possible to develop a preliminary diagram with your own hands, but it is preferable to trust the drawings to a specialist. It must be borne in mind that the complex configuration of the roof requires accurate calculations of rafters and material. All these details will greatly affect the price and installation time.

The drawings must include indications of the purpose of the materials, their installation locations and fastening methods. The most important fragments of the rafters should be included in separate drawings and described in detail.

The production of a drawing diagram can become a support for the manufacture of blanks and subsequent installation.

Preparation

Preparation of rafters is the most difficult and time-consuming stage, because there are:

the need to provide a given angle rafter leg;
different lengths of the narozhnik (short rafter);
the presence of a diagonal rafter (sloping), which is given special treatment.

The slanted rafter carries more significant loads than the main one, for this reason it requires manufacturing from a material more High Quality. Also, the lengths of the diagonal rafters exceed the standard ones.

To avoid buying different lumber, splicing (pairing) of edged boards is used to obtain a given length.

Splicing technology has the following advantages:

continuous beams of a given length are obtained;
increase the strength of diagonal rafters due to large (double) sections;
the calculation and purchase of materials is simplified (length and cross-section dimensions are unified);
it becomes possible to use boards that are designed to form ordinary rafters

Mauerlat is the name given to wooden beams with a large cross-section (100x100 and 100x150 mm), which are mounted along the perimeter of the house. The highest quality wood is used for it.

The peculiarities of the installation of the Mauerlat are that the timber is connected along the length with an overlap, and not end-to-end, and it is attached to the wall using many connecting areas with the base of the walls. The joints are reinforced with metal staples.

The Mauerlat serves as the base of the rafter leg and needs protection from getting wet. Therefore, the wall is separated from the timber by a hydraulic barrier (you can use roofing felt/roof felt, etc.).

If the house is brick, (aerated concrete, foam concrete, wood concrete) the mauerlats are laid on a pre-filled reinforced concrete layer, into which mounting studs are pre-installed. They have a diameter of 10 mm and above and should extend beyond the level of the Mauerlat by 25-35 mm in increments of 1100-1300 mm.

A purlin is a beam that is installed parallel to the Mauerlat. It works as a base when installing additional support under the rafter leg. Arrangement of purlins is an optional stage of work, and is performed during construction hip roof large footage or with a complex configuration.

It is necessary to mount the ridge only with precise measurements. The roof rests on the ridge beam, so it is necessary to install it correctly and check its height.

At the stage of installing the rafter leg, there is a difference of opinion regarding the sequence of operations. Therefore, it is possible to distinguish two directions:

Mount the central rafter, and then the diagonal one. This is a simpler sequence.
Mount the diagonal rafter, then the rest.

The bottom of the rafter legs stands on the mauerlat. To make the connection rigid, it makes sense to strengthen the connecting nodes with metal elements(bracket, plate, corner).

The diagonal rafter experiences significant load, so it is reinforced using means such as:

Installation of racks. Mounted on floors perpendicularly.
Installation of struts. Mounted at angles. Angles are not critical. It is important that the brace strengthens the diagonal rafters.
Sprengels are short T-shaped beams rotated 180 degrees. They are used for significant span lengths and are installed so that the bases of the trusses are oriented across the diagonal rafters.

The ordinary rafter is installed in the same way as the central one, which forms the edge of the trapezoid. The lower parts rest on and are attached to the mauerlat, and the upper parts rest against the ridge beams.

Narozhnik is made strictly from a whole piece of material. Where it adjoins the long rafters, mark a notch or install a support beam. The junction area is reinforced with metal elements.

Narozhnik is installed only after the formed roof frame. This is the last element of installation of the rafter device.

Tools

The design of the roof and the arrangement of connections determine a set of tools that must be prepared before starting work.

When working with wood, you will need levels, hacksaws, hammers, tape measures, marking cords, and staplers.
When working with metal, you will need electric drills, riveters, and metal scissors.

Tools and consumables must be prepared before starting work, since complex installations of rafter systems require a lot of work on cutting various materials.

To simplify measurements and be able to unify the size of parts, it is recommended to replace the tape measure with a measuring rod. It is most often proposed to make such a plywood structure with a width of 50 mm.

Carrying out work

The work is carried out stage by stage and there is no place for haste. Each step must be carefully considered as hip roof designs are complex. In this section step by step instructions It is also hardly possible to cite, since the views of the masters on certain aspects of installation differ too much. Only general recommendations are available.

Rafter system The hip roof 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.

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

Benefits of using a hip hipped roof are aesthetically pleasing and saving consumables.

In addition, the hip roof rafter system is an excellent solution for equipping houses with 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 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 skate. 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 noted as the 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 quantity 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 mowing elements with equal lengths are mounted; the work process is given Special attention, 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 load-bearing walls. WITH the right amount details are 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. Can be used as thermal insulation mineral wool, liquid foam or polyurethane foam.

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.

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.

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.

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 wooden beam, mounted around the entire perimeter of the house at the very top of the walls. It serves to properly transfer and distribute the loads exerted by wind, snow cover, the weight of the roof and the load-bearing walls of the building itself. This element is a connecting upper 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 be of different lengths, 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 the outer wall of the building.

The central rafters are installed with the upper end on ridge beam, the lower ones rest 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 houses large area an increase in their number is allowed.

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. Calculation of the cross-section and number of intermediate elements is carried out based on bearing capacity rafter structure and 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.

Rafter systems in these types of roofs are made in various versions. For example, if the 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

Also highlighted hip roofs. 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. Similar designs They are very complex in design, and their calculation is also difficult. 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.

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, accordingly, a calculation is carried out required quantity material. And if for sheathing 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 characteristics 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°.
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 at top harness. 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 above outer wall by 40–50 cm, and the top one rested on 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.

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 designs, but this does not in any way reduce their popularity. Despite the complexity of construction, they make it possible to arrange additional living space in the attic space, and if done well, you can use it in winter time.

Hip roofs offer an impressive list of compelling benefits. These include an impressive shape, uniform heating and reliable protection of the house from precipitation. Due to the absence of gables, hip structures are not subject to significant wind loads. Compared to 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.

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 will force you to fork out for the purchase of a covering one and a half times more than for arranging a standard pitched structure.

Purchasing piece material 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.

The installation of hanging and layered rafter legs is carried out according to the rules according to which it is constructed. We will deal with their diagonal brothers and 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. Of particular importance The amount of slope does not matter. 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 truss 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 the design features of the 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 truss, a sprung 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 notches 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 with a hipped structure is to purchase and install 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.

Especially if it is planned to be built 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 using a nail gun and metal corners. The contractor will need a 5x25cm board for making rafter legs and purlins, as well as moisture-resistant plywood for the construction continuous sheathing, because the building is planned to be covered with bitumen shingles.

Stage 1: Modeling and Design

Regardless of architectural complexity building structure she needs a project. 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. house wall with dimensions 5x2.5m per homemade drawing will be depicted 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 reserve in case of mistakes in your 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 of a homemade stand such as a high bench and the ridge girder should be placed 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 lower part 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 sheets of inch, 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.

How to build a more complex rafter system for an interesting hip roof, watch the video:

A hip-type rafter system is more complex than the frame of a conventional gable roof, but you can understand its structure. Hip-slope design in many cases it is preferable; it looks more interesting both above houses and above gazebos and other domestic buildings. The described construction option will help you master the basics in the construction hip structures, and if the result is successful, a continuation will certainly follow.

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.

Design features of a hip roof

The hip roof has found wide application in construction due to its strong design features, durability and quite original design, which has a beautiful appearance.

The roof design allows for a spacious residential attic floor with magnificent mortise windows, and the streamlined shape reduces aerodynamic loads from strong winds.

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

Main structural units

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.

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.

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-hip 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 classical one, but in its characteristics it significantly surpasses it.

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 below, but on top there is a vertical pediment that can be replaced beautiful frame with glass.

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.

Broken roofs are very rare due to the complexity of the structure. However, their appearance is so mesmerizing that for a long time you can't take your eyes off her. 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, so it is better to entrust this matter to professional roofers.

DIY hip roof

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.

Tilt 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 erected 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.

Another important factor when calculating the slope is the type of 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 of this material amounts to 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 area calculation

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 geometric figures two trapezoids and triangles. Remembering the school curriculum, it is easy to calculate their total 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 rafter system

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

Roof slope angle ratio	Correction factor for corner rafters	Correction factor for intermediate rafters
3:12	1.016	1.031
4:12	1.027	1.054
5:12	1.043	1.083
6:12	1.061	1.118
7:12	1.082	1.158
8:1 2	1.106	1.202
9:1 2	1.131	1.250
10:12	1.161	1.302
11:12	1.192	1.357
12:12	1.225	1.414

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 rod, find the position ( horizontal projection) 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.

Installation of rafters

Frame reinforcement

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

After the rafter system of the hip roof 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, it should have a solid carpet underneath.