Installation of a hipped roof. Hip roof calculation
Hip roofs attract attention from afar. The apparent simplicity and brevity of the shape of the roof captivates, so the desire to make such a roof is quite natural. What needs to be foreseen for construction and how to properly build a hipped roof with your own hands?
Among all the variety of roofs for private houses, a tent or hip roof is the most economical in terms of materials for construction. Roof slopes are in the form of isosceles triangles that form a common top, and a square acts as the base.
A tent-shaped roof is a kind of hipped roof. Another name for the hipped roof is hip. Its base is a rectangle: 2 side faces are triangular, and the others represent a trapezoid.
The perfect symmetry of the building system and roof slopes requires coordinated actions and accurate calculation when it self-erection... In order to make such a roof, it is important to carefully study the features of its design.
Main elements rafter system hipped roofs are:
- support beam Mauerlat, which acts as a support for the ends of the rafters;
- diagonal rafters located at the corners of the frame;
- supports-struts;
- shortened rafters or rafters, which are attached to the slant rafters;
- additional supports (benches, crossbars and purlins) that create rigidity for the roof.
How to calculate a hipped roof
The main purpose of calculating such a roof is to find the volume of materials required for its construction (roof, roofing material), lathing and installation of the rafter system according to certain parameters... In addition to volumetric parameters, the slope angle of the ramp is calculated, as well as the overall dynamic strength of the system.
Naturally, in terms of the number of parameters, the calculation is quite complex and voluminous, so it is best to use an online calculator, which you can easily find on the net.
As a result of this calculation, you will receive the following data:
- total roof surface area (including overhangs);
- angles of inclination of side rafters;
- the lengths of the side, diagonal and slanting rafters;
- the required number of rafters for the installation of the system;
- recommended rafter section;
- number of rows of crate;
- volumes of timber for rafters.
DIY hipped roof: photo, video, process features
It is better to start erecting a hipped roof with small architectural forms(for example, the roof of a garage or open gazebo). A great occasion to study the technology of roof construction and further improve your skills at work.
Arrangement of the frame
The frame of such a roof has a simple design and consists of four diagonal rafters and eight struts (there are two struts for each rafter).
Roof installation always starts with the construction of the frame. It is important to understand that for wooden houses the frame rests on the upper crowns, for houses made of foam concrete and brick houses- on the Mauerlat.
Installation of support bars and Mauerlat
Mauerlat mounting methods:- using rafter pins;
- using steel wire;
- with anchor bolts.
Fastening the Mauerlat using a wire is performed by laying a steel wire at a distance of 20-30 mm. As soon as the masonry is dry, the wire is wrapped around the timber, after which its ends are fixed.
The studs for fastening the rafters are L-shaped and the immersion depth into the concrete pad is up to 450 mm. Mauerlat is placed and holes are drilled to install the studs. Next, the studs are installed in place, after which they are tightened with a nut.
Regardless of which method of fastening the Mauerlat you have chosen, you need to provide a waterproofing layer. Before the introduction of the studs, the waterproofing material is pierced. After pouring with concrete, you need to calculate the thread of the studs until the concrete has time to harden.
Mounting the Mauerlat on anchor bolts perform directly into the armopoyas before pouring. To mark the holes for the anchor bolts, you need to prepare the board and mark the installation locations on it. Next, the board is applied to the face of the Mauerlat and holes are drilled according to the markings. After preparation, the Mauerlat is put on the bolts, a washer is placed, then the nut is tightened.
Arrangement of the rafter system
After aligning the Mauerlat along the perimeter of the roof, you can proceed to the installation of the rafter system, namely the diagonal rafters located along the diagonals of the hipped roof. At the same time, keep in mind that the main load of the system falls precisely on the diagonal rafters. Diagonal beams are of considerable length and weight.
Their installation is carried out according to the calculated non-thrust or spacer scheme, according to which the rafter leg of the beam can abut against the beam or Mauerlat. The angle of inclination of the rafters can be up to 23 °. The second pair of rafters is installed in exactly the same way. After installing the diagonal rafters, 2 short struts are adjacent to them.
During operation, there may be a need to cut off the upper face of the attachment rafter. It must be laid on the edge at an angle. The layer in the valley is cut off with a groove. Thus, laying the battens is much easier.Useful tips for building a hipped roof
According to the selected project, all operations during the construction of a hipped roof - the construction of the lathing, the device of the valley, the framing of openings and pipes are carried out during the installation of the rafter system. Accurate adherence to construction technology will provide an excellent result.
The structure of the rafter system directly depends on the choice of the type of roof. The hipped roof rearranges a rectangle, the structure of which is considered one of the most complex. The design has four identical slopes, but if desired, their number can change, the main thing is to observe symmetry. In this article, we will tell you how the hipped roof rafter system consists.
The photo shows a diagram of the rafters tent structure.
The hipped roof refers to the hipped roof type of structures and has the shape of a hipped roof. The structure of the rafter system is presented in the form of an isosceles triangle connecting at one point, and the base is made in the form of a polygon. The square hipped roof base is considered classic, however, its structure can be made in a different form. The hipped roof can be made in the following configuration:
- trapezoidal slopes;
- mansard roof;
- bay window or yandovaya roof;
- domed slopes and round base;
- the presence of six or eight bases.
For information! When device classic form it is recommended to use the calculations of the rafter system of the hipped roof, taking into account the current building codes and rules.
Advantages and disadvantages
The photo shows a house with a hipped roof. Despite the complexity of the structure of the rafter system of the tent structure, its popularity in the design of private houses is quite high. Experts note the following advantages of the tent structure:
- High aerodynamic performance, allowing to reliably protect the hip-roof roof from strong and squally gusts of wind, without tearing off the roofing material and collapsing the attic;
- The presence of steep slopes excludes the process of cleaning the roof from snow and debris;
- The hipped roof allows you to expand the usable area of the house and equip the attic;
- Gives original appearance any structure;
- High structural strength, reliable protection from freezing and precipitation.
Among the shortcomings, the following should be noted:
- A large amount of consumables;
- The absence of gables suggests installation roof windows that are fixed directly into the ramp.
Hip structure device
The hipped roof and the rafter system can be arranged in two ways: hanging or inclined. A complex of rafters of an inclined type is considered the most economical and simpler in the device. The main structural elements of the hipped roof consist of:
- The ridge knot is an element where all the rafter legs are connected, forming its apex point;
- The presence of a triangular slope, the rafters provide support and form the surface of the structure. The angle of inclination should be 20-50 degrees regardless of the number of roof corners;
- Overhangs - this element performs protective function buildings from precipitation and wind gusts. Filly and rafter legs are responsible for the quality formation of overhangs.
For information! Overhangs are able to reliably protect the building provided permissible length element, therefore, when performing calculations, take into account the length of the overhang of at least 50 cm.
- Roof covering - construction material covering the rafter system of the entire structure. The main task of the roofing material is to protect the entire plane from the penetration of snow, rain and cold. Most often, metal tiles, slate, roofing material, ondulin are used as the material.
- Rafter system - important element tent structure, performs a support function, is able to reflect the load and prevents the destruction of the foundation, load-bearing elements of the structure;
- Drainage system- is responsible for the unimpeded release of moisture into storm sewer... The complex includes vertical pipes, funnels and gutters.
Features of the rafter system
Hip roof structures can be made with a layered or hanging system. Hanging rafters are mounted when there are no internal walls in the house, and the rafter system rests directly on bearing structures at home. The photo shows specifications hanging rafter systems. The layered rafter system assumes fixation to the middle load-bearing wall or on supporting pillars that are firmly fixed with reinforced concrete.
For information! For hipped roofs with an angle of inclination equal to 40 degrees and higher, it is recommended to perform layered rafters.
An important point is correct selection supports for the rafter system. For example, for frame structure use the top harness, brick house the function of support is played by the Mauerlat, and the upper crowns are used in log houses.
Calculation of the tent rafter system
The following measurements will help to avoid mistakes and perform all calculations:
- length eaves;
- the main parameters of the slopes (angle of inclination, length, width);
- type of base shape,
- width and length of the roof base.
When all the calculations are completed, a drawing of the rafter complex should be made. As a rule, for this you can use a special online service, with the help of which you can make the correct calculations of the roofing material.
If you turned to specialists for help, the design of the future structure begins with the execution of the drawing, namely the drawing of the contours of the structure. When performing a roof drawing, the height of the structure does not depend on the height of the walls, however, this parameter should be taken into account when calculating snow and wind loads.
For information! With a small angle of inclination, there is a risk of precipitation stagnation over the entire roof plane. Experts recommend using a tilt angle of 30-60 degrees.
For more details on how to independently perform calculations of the rafter system of a hipped roof, see the video.
The calculation of the rafter system is performed using the Pythagorean theorem. If the base of the structure is square, the slopes will be like an isosceles triangle with the same angle of inclination and their dimensions. To simplify the task, it is recommended to calculate the rafters on one element and transfer the obtained data to the remaining fragments of the complex.
The hipped-roof structure implies too much consumption of building and roofing materials, because when performing work, it will be necessary to perform a large number of cuts. However, this high-quality and reliable roof will be able to protect the house from various influences. external environment and her original view will attract the attention of others.
The roof of the building is its main protection. The variety of shapes, structures, types of roofing systems allows you to design a building in such a way that it will receive an individual look, become pride and a warm family nest for any family.
Roofs by structural features, the specificity of the shape of the slopes can be of several types:
- Flat... The sides of the structure rest on the walls of the building. They are practically devoid of bias. The shape of the slope is most often a rectangle;
- pitched... The design has two or more slopes of various shapes that are located at a certain slope.
Pitched roofs are classified by number, shape, location of slopes:
- Gable;
- hip;
- half-hip;
- tent;
- multi-pliers;
- domed.
In addition, there are other designs that are less common. They are occasionally used in roofing structures: steeple, vaulted, arched, spherical, folded.
There is something to choose from a variety of roofing systems: each of the structures has its own installation features, characteristic architectural design, individual functionality.
The design of the hipped roof is characterized by such a device in which the slopes are made in the form of triangles with common point connections of four vertices.
The number of triangles in the structure of a hipped roof can be more, but they must all have a common top. Ideal option building a room for a hipped roof is a quadrangular shape, in which the top of the roof is formed in the center.
But the tent system may not necessarily have an apex in the center of the structure. The roof can be installed in such a way that the top is offset from the center to the side... In this design, the length of the sides of two opposite slopes at four-slope system different.
By design features structure of the truss system hipped roofs can be:
- Fortified... Have pivot points on external and interior walls ah, the distance between which is not more than 4.5 meters;
- hanging... They are built with a small span and without the need for additional internal supports.
Regardless of which rafter system is mounted when arranging a hipped roof, its external shape remains unchanged.
Besides, by design features, hipped roofs can be:
- Broken lines... More often installed under the attic, while there is a change in the angle of inclination on the slope to a smaller one;
- with bay window (valley). Hipped roof at the same time it is an addition to the bay window;
- attic... In this case, the attic ledges are located on the roof slopes.
Regardless of the structure of the tent system, the shape of the roof is similar to that of a tent: hence the name.
Hipped roof of a private house
Advantages and disadvantages
Can not be perfect design roofs: each has its own individual characteristics.
An important advantage of the hipped roof is its aerodynamic properties.: wind currents pass along the slopes, without harming the roof, and do not enter the attic space. In addition, the absence of gables ensures the stability of the structure.
The disadvantages of the tent structure is the complexity of installation., as well as if you want to equip the attic, its area will be too small.
Despite the fact that the construction of a hipped roof requires significant labor resources, the end result will definitely be justified: tent structures are among the most attractive roofing systems.
Advantages and disadvantages
What elements does the hipped roof consist of?
Standard tent construction system consists of elements:
- Slant rafters... Planks located in the corner parts of the system frame distribute a significant part of the load acting on the entire system. They are the longest rafter parts of the structure;
- wives... Serve to strengthen the rafters and distribute the load;
- ridge knot. Complex element, since the rafter boards are not always ideally fastened if the roof is not square;
- central rafters... They are connected in the ridge part with the slanting beams and are an indicator of the height of the slope;
- struts... They are the supporting parts of the rafter legs;
- mauerlat... Support rails for the entire structure, to which the rafter legs are attached. A bar with a large section is used for the Mauerlat.
Additional elements of the system are crossbars, additional supports, purlins, slopes, that is, those elements that serve to strengthen the main parts of the structure. They are most often used in regions prone to strong wind currents..
Drawing of hip roof elements:
The elements
DIY hipped roof: construction sequence
A feature of the construction of the hipped roof truss system is that the installation of its base is carried out on the ground in accordance with pre-prepared templates. To make a template, you should take into account the length of the rafters, the pitch, the load and the corresponding section..
Do-it-yourself construction of such a roof involves the following work:
- Mauerlat installation;
- installation of rafters;
- installation of struts, central supports;
- installation of handicrafts;
- installation of the lathing;
- installation of vapor barrier;
- installation of waterproofing;
- roof covering.
Each stage of work involves the implementation of mandatory steps, without which the arrangement of the roof will be disrupted.
DIY construction
The device of the rafter system and installation
The rafter system of the hipped roof is a rather complex structure. In addition, the installation of the hipped roof structure should be carried out before making the ceiling of the building.
Installation is carried out in stages:
- Install the Mauerlat (if the walls are brick): it is fastened by external load-bearing walls, having previously covered them with a waterproofing layer (roofing material is most often used). If the walls are made of wood, mount the harness;
- from opposite corners, set-up rafter boards are installed and fastened in the ridge by means of fastening puffs. At the same time, the upper ends are cut at an angle. rafter boards... It is recommended to use a mortise beam for attachment to the Mauerlat. At wooden wall they are fastened with brackets, if the wall is made of brick, reinforcement clamps are previously mounted in the Mauerlat;
- in the central part of the trusses, props are installed;
- in the pitched parts, braces, struts, diagonal slats are installed... This ensures resistance to wind loads;
- installation of braces, struts, sprengels.
When arranging diagonal rafters, you should adhere to a right angle.
Mauerlat installation
Roofing cake
Roof cake is a series of layers of materials for arranging the roof.
For a hipped roof, the cake consists of such layers:
- Rafter system... Made from wooden beams, serves as a massive framework for the entire system;
- vapor barrier... Condensation prevention layer;
- lathing... A plank system that provides structural strength and is the basis for fastening the layers of the cake;
- insulation... Serves for insulation of the roof and the building as a whole;
- waterproofing... Material that prevents moisture from entering from outside;
- counter-lattice. Wooden structure which serves to provide ventilation gap between the roofing material and the layers of the cake, as well as for attaching the outer cover;
- roofing material... The outer coating is the main protection against external factors.
CAREFULLY!
The correct sequence of stacked layers of the cake ensures its reliability and creates a comfortable microclimate. If mistakes are made in arranging at least one layer, this can cause the destruction of the entire roof.
Photo of the hipped roof scheme:
Installation of lathing, waterproofing and vapor barrier
The method of installing the battens directly depends on the roofing: if provided soft roof what is advisable to mount solid crate if rigid - sparse.
The crate is made of boards, the width of which is not more than 150 mm, and the thickness is about 2.5 cm. The boards are installed on a vapor barrier layer on top of the rafters (along). Sheathing is carried out around the entire perimeter of the roof.
The waterproofing layer is a membrane that does not allow moisture to pass into the roof from the side of the roof covering. Roofing material, other rolled membranes, as well as modern "smart" (breathable) membranes, which prevent atmospheric moisture from entering the insulation, can serve as waterproofing.
Waterproofing is fastened with staples to the rafter legs... The docking joint is made with an overlap (at least 10 cm), and the joints are glued with tape. Lay the film in such a way that the lower overhang of the material is on the eaves, and the top is near the top.
Vapor barrier is made of specially designed films that prevent condensation drops from entering the roof insulation from the room. As a vapor barrier, vapor barrier membranes, films, special polyethylene and propylene films are used.
The vapor barrier is attached to the lathing with an overlap with staples so that strong tension does not form. The joints are glued with adhesive tape (tape). Fix the film with crate boards.
After fixing the crate, insulation is placed between its boards.
Laying waterproofing
Installation of the lathing
Insulation of the hipped roof
The need to insulate a hipped roof is especially relevant if the structure provides for the equipment of an attic room.
However, it will not be superfluous if the insulation is produced without living space directly under the roof.
Common roof insulation materials are: mineral wool, penoplex, expanded polystyrene and others.
The most popular material is mineral wool... When insulating a hipped roof, layers of material are laid between the rafter beams from top to bottom so that no gaps are formed. This is how the insulation is laid on all roof slopes.
Insulation must have a number of characteristics that can help ensure reliable insulation.:
- Low thermal conductivity;
- compressive strength;
- density;
- fire resistance;
- vapor permeability;
- breathability.
Warming
Laying roofing
For hipped roofs, an important indicator of the choice of roofing material is the slope angle of the slopes.
For different coverage the possibility of laying it in accordance with the slope is determined:
- Roof tiles - from 30 to 60 °;
- asbestos-cement coating - from 14 to 16 °;
- soft roof - from 8 to 18 °.
Alternatively, one can use decorative coatings, typical for this type of roof - reed, reed. Such coatings are short-lived; for the central region, they are less common, taking into account climatic features.
Often tent systems covered with tiles and other sheet types (corrugated board, sheet copper, metal tiles).
Covering with roofing material must be done on each slope in turn.... The peculiarities of the laying of each material provide for the fulfillment of the installation requirements.
So, for example, sheets of corrugated board should be started to be laid from the lower left edge of the slope and continue to be covered, securing with special self-tapping screws. In this case, the edges of the sheet are cut diagonally from the edge of the slope.
ATTENTION!
The calculation of the outer covering of the hipped roof should be made taking into account a sufficient amount of material scraps.
Although the waste can be used on the tops of the ramp, there will still be plenty of it.
Laying of roofing material
Conclusion
Thus, you can do the installation of a hipped roof with your own hands, but the work will require maximum effort not only to install the roof frame, but also to lay the layers of the pie.
This is due not only to physical work, but also to the correctness of calculations for the load and consumption of materials. complex design... But all the effort and money spent will more than cover the uniqueness of the design.
In contact with
At one of the stages of a project for the construction of a private house outside the city, you will think about the shape of the roof. Hip or hip roof is the most popular at the present time. Its appearance and construction are reminiscent of a tent. This roof has its pros and cons. You don't have to hire specialists to install and install this one. You can easily assemble the roof frame with your own hands. To do this, you need to be able to make calculations and have an understanding of the structure and mechanism. It must be remembered that the roof is attached in the same way as other structures. For more confidence, you can call an assistant.
The main advantage of the hipped roof design is aerodynamics, it resists strong gusty winds. Air currents will leave along the slopes without causing harm, and without even going into the attic.
The main disadvantage of such a roof is a complex frame, its sheet installation and the fact that it is very small. Of course, the area of the attic is equal to the area of the ceiling, but the useful volume of the room is very small.
The classic-type hipped roof mechanism is a special pyramid with a square or rectangular base. Triangular slopes and trapezoidal ones, as a rule, rest on or go beyond them.
The main scheme of the hipped roof of the house is quite simple, and you can calculate it different ways... The hipped roof is installed using the system and the Pythagorean table. And it will not be difficult for you to calculate the area of the slopes and hips, but the calculation of the location and installation of the rafters and ordinary rafters takes a lot of time. 
The construction of a hipped roof begins with assembly. After that . The mechanism of the rafter system is quite complex. Below we will consider in more detail how to make a frame, make a calculation and make a roof.
The manufacture and installation of the roof follows the following rules:
- For the construction of the ridge system, the same wood and material are used.
- Intermediate boards have a steeper angle of inclination, and their size must be at least 50x150 mm.
- Short pieces and pieces are attached to the corner components of the rafters, not to the ridge board.
- During construction, intermediate central rafters are used in the structure, fixed on the ridge board.
- And they should rest against the upper end of the harness or against the ridge board.
To assemble and install a hipped roof with your own hands, you need to imagine a certain roof frame of the house and make a preliminary drawing.
The drawing must be fixed following items hipped roof:
- the central part of the structure - the ridge, is the bearing axis;
- nipple rafters are the power components of the rafter, one end will protrude outside the house, and the other will be attached to the ridge;
- rafters of the central type are attached at the ends of the ridge and are displayed on all walls;
- intermediate rafters extending from the ridge must go strictly along the slopes;
DIY hipped roof
The installation and assembly of the hipped roof must be done before laying the ceiling.
At the beginning of work, a bar is laid around the entire perimeter of the house for more uniform distribution masses over the entire surface. It is also called Mauerlat. It must be fixed to the house using special pins.
- mark the axis from the end frame house on the upper harness;
- calculate half the thickness of the ridge beam and mark the installation location of the initial element of the rafter system;
- attach one end of the measuring rod to the marked line and mark the place of the intermediate rafter;
- to calculate the overhang of the rafters, one end must be placed on the overhang of the roof, and the other at an angle with outside walls of the house;
- you can calculate the location of other elements of the rafters of the central type by moving the rail along the side wall of the house and marking the position of each rafter;
- at the other corners, the same is repeated;
- you can buy roofing materials in special hardware stores. Today the market offers a wide selection of roofing optimal quality at an affordable price.
Calculation of hip roof elements
For this calculation, you will need a special measuring rod.... It runs from standard width 5 cm. There is a special table of rafter length and position ratios.
Thanks to these data, which are presented in detail in the table, the length of the rafter leg is the product of an intermediate or slope its projection. To increase the accuracy and reliability of calculations, be sure to use this table. Consider an example of a roof, you measured a horizontal projection of an intermediate type rafter with a rail.
From the table, you will find the angle of inclination that suits your case, and multiply the data.
You can also calculate the length of the overhang of the rafters. You need to multiply the horizontal projection by a certain factor. Also, these data can be calculated using the Pythagorean theorem for a right-angled triangle by the formula: a2 + b2 = c2. Where a and b are horizontal and vertical projections.
Corner elements
All rafters have an oblique cut on one side, which is necessary for attaching to the ridge beam. The ridge has a special undercut with a double bevel for more reliable fixation of parts and elements in the corners of the house.
And the calculation of corner-type rafters is as follows:
- from the corner you need to measure the full length of the rafters;
- its projection will be the product of the squares of the lengths of the rafter central projections.
The resulting number must be multiplied by the coefficient indicated in the table, and you get the length of the corner rafter.
Then the area of the triangular slopes is calculated. They are also calculated by the Pythagorean theorem. To simplify the calculations, you need to represent the ramp in the form of two right-angled triangles... Next, calculate the area of the trapezoid of the side surface of the roof of the house using the formula.
And already at the very end we calculate the roof. The indicators of all areas must be summed up, and you get the minimum roof area.
Tools and building materials
For the device of the structure of the hip roof with your own hands, you will need special Building tools and materials such as:, electric, hand saw, nails and dowels, hammer, plane, ax, electric drill, beams and boards of the same species of wood, material, steel staples.
You can build a standard tent type, either elongated to one side or in the form of a truncated pyramid.
Do-it-yourself frame installation
Initially, verticals for the ridge bar are mounted. After that, the installation of diagonal rafters of the same length begins.
Next comes the installation of the skate, and then the privates with a certain step of 60 cm, which are fixed with a cut to the ridge and. You can do the cut with your own hands or with a special power tool.
Then, on the diagonal guides, the hangers are fixed, for a bundle of the cut-off beams and the Mauerlat at a certain angle relative to the ridge of the roof.
An important point, ordinary bars should in no case touch the connection points of the Mauerlat.
Strengthening the roof will directly depend on the dimensions of the house. An additional truss is laid, i.e. between the adjacent sides of the rafters. And already a rack or truss truss is installed on it. With very large area houses for diagonals use double beams.
The hipped roof structure consists of triangular slopes. As a rule, the number of stingrays is four, but the owner can change their number if desired. The main thing that finished structure was robust and symmetrical.
Outwardly, such a roofing structure looks like a tent, for which it got its name. As part of the roof there are no gables, which makes it possible to additionally save on building and finishing roofing materials. Subject to proper arrangement, such a roof will have an attractive and original appearance.
Arrangement of a hipped roof requires special knowledge and skills from the performer. With the construction of a tent roof structure you can do it yourself. The main thing is to do it right necessary calculations and strictly follow the instructions when performing each activity.
Before going to the store for the required materials, familiarize yourself with the procedure for performing calculations and draw up a roof project that is suitable specifically for your case.
Basic information
Traditionally, the roof under consideration includes 4 inclined slopes.
If the base of the structure is in the shape of a regular square, the area of the structure is calculated by multiplying the area of one roof slope by 4.
However, if the base of the system looks like a rectangle, then first you need to determine the total value of the areas of two different rectangles, and then double the resulting number.
To establish the area of the roof slope, which is an isosceles triangle, it is necessary to multiply the length of the base of the figure by the value of its height, and then double the resulting number.
When performing calculations, you need to find out the value of the area of the eaves overhangs in the form of isosceles trapezoids. This calculation is done by multiplying the height of the shape by exactly 50% of the sum of the base lengths of the trapezoidal shape.
The calculation of the hipped roof system can be done in two ways. The first involves a calculation using the value of the ridge height and the length of the base of the roof structure. In accordance with the second calculation method, it is necessary to take into account the value of the length of the diagonal rafter element as well as the length of the perimeter of the base.
In addition, in the calculation process, it is imperative to pay attention to the parameters of various additional components that make up the roof structure. These elements include:
- diagonal rafter legs;
- lie down;
- support bars;
- racks;
- mauerlat, etc.
Calculation example
To make the calculation principle clearer, we offer you a simple example of the implementation of the basic calculation activities. Initial data:
- house dimensions - 6x6 m;
- the length of the diagonal rafter is 521 cm;
- ridge height - 297 cm;
- slope of roof slopes - 35 degrees;
- width of the eaves overhang - 600 mm.
Using the first of the two previously mentioned methods, determine the value of the height of the roofing triangle. To do this, use the Pythagorean theorem, according to which to calculate the square of the height, you need to subtract from the value of the square of the length of the roof slope half the width of the base, also squared.
In this example, the calculation will show that the square of the height is 4.24 m squared. Using a simple formula, you can determine that the area of one triangular slope will be 12.72 m 2.
Due to the fact that the base of the roof is a square with a side of 6 m, the calculated value of the area must be increased by 4 times. As a result, you will determine the total area of the roof slopes equal to this example 50.88 m 2.
Determine the area of the cornice light. You already know the length of the shorter base of the trapezoidal figure - 6 m.To establish the length of the larger base, you need to use simplest form relevant for such figures.
According to the calculations, the length of the larger base will be 704 cm, and the area of the figure as a result will be 4.76 m 2.
To set the total area of the overhangs, multiply the value calculated in the previous step by 4.
As a result, the total amount of the hipped roof structure will be 69.91 m 2.
What you need to know about the rafter system?
The hipped roof structure can be erected using a layered or hanging system. The final version is selected in accordance with the conditions of a particular situation.
For example, it is quite difficult to cope with the installation of hanging rafters with your own hands, and it will take an irrationally long time to repair such a structure. Such rafters are usually equipped in situations where there are no internal walls in the house, and the rafters can only rely on the supporting walls of the structure.
Roof rafters are simpler and more financially beneficial in arrangement. The system is placed on the middle load-bearing wall, as well as intermediate support pillars fixed on a reinforced concrete base.
Reinforced rafters are most often used when installing four-pitched roof structures with an inclination of more than 40 degrees.
It is important to choose correct option system supports roof rafters... If the house is frame, the roof must be supported by the upper harness. In the case of brick and stone buildings, the Mauerlat performs the function of support, and when arranging the roof of a house from a log house, the roofing system is fixed to the upper crowns.
Determine the optimal cross-section of the rafter legs. To do this, you need to know a number of parameters, namely:
- step of mounting the elements of the rafter system;
- slope of roof slopes;
- estimated snow, wind and other loads;
- span size, etc.
It is important to know the basic parameters of tent-type roofing elements.
So, if the rafter legs have a length not exceeding 300 cm, the rafters must be placed in increments of 110-135 cm. Optimum diameter logs for such a situation are 100 mm, and the size of the board is 100x80 mm.
If the rafter legs have a length in the range from 300 to 400 cm, they need to be fixed at a distance of 140-170 cm. For arranging such a rafter system, it is recommended to use logs with a diameter of 150 mm or boards with dimensions of 100x90 mm.
If the rafters have a length in the range of 400-500 cm, they must be fastened in increments of 110-135 cm, using logs with a diameter of 200 mm for arranging the structure, as well as boards with dimensions of 200x80 mm.
When arranging a rafter system of elements no longer than 650 cm in length, the rafters must be placed in increments of 110-140 cm, using logs with a diameter of 240 mm or boards with dimensions of 220x120 mm to equip the structure.
For the arrangement of the purlins, use a beam of 100x50 mm or logs with a diameter of 160 mm.
Mauerlat is traditionally erected from a 100x50 mm bar or a log with a diameter of 120 mm.
Racks, crossbars and struts are made from a bar with a section of 100x50 mm or logs with a diameter of 120 mm.
It is important that the rafter legs are strictly the same length, and the rafters are docked apart.
The most common slope of the slopes of hip roof structures is maintained in the range of 40-60 degrees, however, depending on the parameters of the finishing roofing material, the slope may vary slightly. The dependency is as follows:
- when using tiles, the slope is maintained within 30-60 degrees;
- when using sheet roofing materials and materials based on asbestos cement, the slope will be in the range from 14 to 60 degrees;
- using roll materials the slope will be 8-18 degrees.
Roof installation procedure
The process of arranging a hipped roof includes several stages.
First step
Draw up a structural project and make the necessary calculations in accordance with the recommendations given earlier.
Second phase
Buy the required amount of materials, taking into account the dimensions and characteristics approved by the project.
Stage three
Lay the Mauerlat along the entire length of the building. Rafter legs will be installed on it.
If the house is built of bricks, the Mauerlat is best laid on the inside of the walls. In this case, a moisture-proof material must be laid between the Mauerlat and the wall. For waterproofing, roofing material is often used. To prevent the rafter legs from sagging, you need to mount the lattice with the appropriate parameters.
If the house is built of wood, in most cases the upper part of the frame will be able to cope with the functions of the Mauerlat.
Fourth stage
Install the rafter support beam (purlin) at the top truss structure... The support beam must be placed parallel to the Mauerlat. The recommended distance between the two mentioned elements is up to 450 cm.
Fifth stage
Install diagonal braces, braces and struts.
For the manufacture of diagonal ties, boards of 250-450 mm are usually used. They must be nailed to the base of the rafter leg.
You need to equip the planned number of ramps (usually 4). At this stage, work according to the blueprints you have.
Sixth stage
Insulate the roof. Attached first waterproofing material, a heater is placed under it, and a membrane vapor barrier film is placed under the heater.
In the end, you just have to lay the desired finishing roofing material and install all kinds of additional elements like gutters, etc.
Now you are aware of the main features of the hipped roof structure, you know in what order the system is calculated, what its main elements should be, and in what sequence the roof is arranged directly. Follow the instructions, while focusing on the provisions of the existing project, and everything will definitely work out.
Happy work!
Video - Do-it-yourself hip roof
