How to make a mansard roof of a house from a bar. Mansard roof - technology for the construction of a mansard roof of a private house. Types of rafters for attics

In an effort to efficiently use the entire available area country house many owners equip the attic. When doing this, you must be prepared to arrange the roof in a certain way. At its core, the attic is a converted attic and requires certain constructive solutions and some alterations in thermal insulation and roofing. In general, the construction of a mansard roof of a country house is not much different from the construction of other types of roofs. But due to the operational features of the attic roof and the requirements for it, it is necessary to have knowledge and understanding of the specifics of arranging this type of roof.

Types of mansard roofs

Like any construction works, the construction of the attic roof begins with the design stage and the selection of the most suitable mansard roof for the structure, its type and type. For the attic, single-pitched or ordinary and broken gable roofs are used. In addition to everything else, appearance roofs are affected by the materials used and design features the roof itself.

Depending on the structural features of the building itself, during the construction of the attic, several standard solutions for the roof. Mansard roofs: photo and description

gable roof for a single-level attic. This option is a conventional gable roof, under which an attic is built. During the design and construction, there are no great difficulties due to the simplicity of calculations and the ease of work on the construction of the truss structure. The main disadvantage of this roof design is the small attic interior with rather low ceilings.

Sloping gable roof for a single-level attic. Unlike the usual gable roof for the attic, the broken structure uses 4 pitched planes located at different angles. This type of roof structure is somewhat more difficult to design and build, but its undeniable advantage is the full-sized interior space.

One level mansard roof with remote consoles. The design of this type of roof is more complex than the previous ones. But spacious room and full-fledged vertical windows compensate for the shortcomings in the complexity of design and construction. The design feature of the attic with such a roof is its displacement and extension beyond one of the sides of the house, and the roof is more like a shed.

Two-level mansard roof with a mixed type of support. Roofs of this type are the most difficult to design and build. Such roofs are designed in conjunction with the house, as a whole, due to the multi-level placement of rooms.

Various projects of mansard roofs in their design are not much different from ordinary ones. pitched roofs. Of course, there are certain design features, but in general they are the same as gable or single slope, and consist of the following main elements:

. Roof. The outer part of the roof, which performs the function of protection from various atmospheric phenomena.

. crate. More often wooden planks to which the roof is attached, as well as insulating materials.

. Skate run. The upper part of the entire truss structure.

. rafters. These are the stiffeners of the entire roof structure, they can be layered and hanging. For the roof of the attic, layered rafters are used.

. Mauerlat. This structural element consists of beams laid along the perimeter of the external walls and connected to the walls using special fasteners. The entire truss structure is attached to the Mauerlat.

.Diagonal ties. To ensure the reliability and strength of the entire truss structure, the rafters are connected to the longitudinal beams and vertical posts using diagonal ties or bevels.

. Internal supports. To stabilize the roof, the rafters and/or ridge run supported by vertical beams.

. insulating layer . Due to the fact that the roof of the attic and the interior are practically one whole, a multi-layer insulating cake is laid between the roof and walls of the room to maintain the temperature and humidity conditions. The insulation consists of hydro and vapor barriers, sound and noise insulation, as well as a thick layer of thermal insulation. In addition, proper insulation of the attic roof is also important for the safety of the roof itself.

Mansard roof construction technology

When designing and erecting a mansard roof, many builders and designers, either out of ignorance or doing their job somehow, make serious mistakes in insulation, ventilation and truss construction. As a result, a mansard roof is obtained, which, literally after a couple of seasons, becomes unusable, fungus, mold appear, and the roof begins to leak or completely collapses. This happens due to a violation of the construction technology of the mansard roof.

Due to the fact that the roof of the attic is maximally attracted to the walls interior, and it is rather difficult to obtain excellent heat transfer indicators in this case, the entire structure of the mansard roof must have excellent thermal insulation, ventilation and a properly erected truss structure using wood treated with fire and biological protection.

To make the attic roof reliable and durable, you need to know the following:

the thickness of the rafters must be more than 250 mm. For such rafters, you can use glued laminated timber;
as thermal insulation, use materials that will not lose their properties in case of increased humidity. For example, extruded expanded polystyrene or foamed glass;
between the roof and the thermal insulation layer we make full ventilation with air vents and exhaust hoods, through which air will circulate under the entire surface of the roof;
With inside over the entire surface of the thermal insulation, it is necessary to equip a layer of vapor barrier;
With outside rafters under the roof fit a layer of waterproofing and, if necessary, a layer of sound insulation.

Such requirements are due to certain natural and physical phenomena. But first things first:

A large thickness of the rafters is required to be able to lay a layer of thermal insulation between them with a thickness of 20 cm, and this, in turn, entails an increase in the mass of the entire roof structure, which is held by the rafters.

Wood for the whole structure is processed by special means for protection against fire and microorganisms, which is a strict requirement of SNiP. This will protect it from damage by fungi and increase its service life.

If you use such popular materials as mineral and glass wool for thermal insulation, then you can win only in the convenience of installation and lightening the entire structure as a whole. But cotton wool, whatever it is, is cotton wool, which, like a sponge, absorbs water, cakes and loses its insulating qualities. If you choose any material other than polystyrene and foamed glass, you should focus on complete resistance to moisture, low heat transfer coefficient and relatively low weight.

The thickness of thermal insulation of 20 cm is necessary because in our latitudes it is very cold in winter and very hot in summer. A feature of the design of the attic are large heat losses in winter and rapid heating of the room in summer. A large layer of thermal insulation will prevent heat loss and its penetration inside. But this is only one of the reasons, the second is the safety of the roof. The fact is that the heat that leaves their premises in winter heats up the roof, on which lies a layer of snow and partially causes it to thaw, and snow is a natural insulation. Melted snow at sub-zero temperatures turns into ice, which has no thermal insulation properties, it makes the roof heavier and finally destroys the roof itself. And since up to 100 thawing and freezing cycles can take place in one day, the roofing material will fail in just one season. In the summer, the room becomes incredibly hot and stuffy, and an air conditioner, or even two, is required. But these inconveniences can be avoided by equipping a thick layer of proper thermal insulation.

Equally important is the full ventilation of the roof. It will help to cool the roof, both in summer and winter, as well as remove excess moisture from under the roof. All this will provide comfortable accommodation in the attic room, it will protect against the appearance of mold, fungi and rot, in addition, it will keep the roof from destruction in winter.

Regarding steam, hydro and sound insulation, then everything is simple. Vapor barrier passes through itself excess moisture from the side of the premises and prevents its penetration from the outside, waterproofing protects the heat-insulating materials and the premises from accidental ingress of moisture. And soundproofing reduces the level of noise from rain, hail and wind impacts on the roof surface.

Phased construction of a mansard roof

The implementation of all work on creating a roof for the attic requires builders to have some experience in this area. Unlike conventional pitched roofs, building a mansard roof with your own hands is somewhat more difficult due to the arrangement of windows located at an angle in the roof itself and the broken structure of the slopes. To build a mansard roof with your own hands, you must adhere to next steps works:

Design

The first thing to do is to develop a roof project. To do this, you can turn to specialists or, if you are good with a computer, do everything yourself in an architectural program. Also at this stage, all necessary calculations loads, angle of inclination of roof slopes, etc. To do it right, you need to contact necessary information to such a document as SNiP "Loads and Impacts".

The construction of the truss frame

This stage of work is the most time-consuming, and in order for the mansard roof to be made with high quality by hand, the combined efforts of 3-4 people will be required. We begin the construction of the attic roof with laying and fixing the Mauerlats around the entire perimeter of the house, using a bar with a section of 100x100 mm.

Mansard roof construction photo:

After that, we install a frame for the attic, the racks of which will also serve as supports for the roof structure. To do this, we use a bar with a section not less than the section of the longitudinal beams on which the racks will rest. First of all, we install vertical racks at the beginning and at the end of the building. We fix them to the longitudinal beams using special stamped metal corners and self-tapping screws. To facilitate all work on fasteners, we use a screwdriver. Now we lay a jumper on top of the racks and fix it.

We stretch the cord between the two received arches, and if everything was done correctly, it will be strictly along the horizon, if not, you will have to disassemble one of the arches, cut it a little and reinstall it. Now, along the stretched cord, we install similar arches with a step that is provided for the rafters. We connect the resulting arches with jumpers, which we fix with stamped corners or nail plates.

Having assembled the frame of the future interior, we proceed to install the rafters. We start with those that have the largest angle of inclination and are on the same level with the frame of the attic room. There are no special difficulties here. The beam for the rafters is cut to the desired estimated length, a groove is cut at the base of the beam for installation on the Mauerlat, and the top is cut at a certain angle. After that, each rafter is installed in place and fixed to the main structure.

The next step is a little more difficult, as you will have to install the upper rafters. The difficulty lies in maintaining a certain angle and centering of the entire structure. To facilitate the task, you can first make a template from two long boards that will exactly repeat the future connected rafters. Using this template, we cut the rafters on the ground and then set them in place. The installation algorithm for the rafters is the same as for the arches of the frame of the interior.

At the end of the installation of the rafter structure, we nail the crate. For crates can be used as ordinary boards, and sheets of plywood or chipboard. This will already depend on the type of roofing materials.

Making an Insulation Pie

Having installed the rafters and the crate, we proceed to create an insulating layer. To do this, first of all, we lay a vapor barrier on the inside of the rafters and fix it to the rafters with brackets. Next, we lay thermal insulation material and we carefully monitor that it lies close to the rafters and does not leave gaps. On top of the thermal insulation, in increments of 50 cm, we fill the crate, which will hold all the thermal insulation.

On the outside of the rafters, we lay a layer of waterproofing, which will protect against accidental penetration of moisture. Finally, we lay the roof over the waterproofing.

Mansard roof construction: video tutorial

The variety of ready-made attic roof projects is very extensive. They can be with or without windows, rounded or strictly straight, with one slope or several. But whatever the roof of the attic, its construction will require the knowledge and skills of a construction master.

The device of the mansard roof allows you to significantly increase usable area and rationally organize the space of a low-rise building. However, its construction often frightens home craftsmen with an overly complicated and time-consuming process.

You should not be afraid, because the result will provide beautiful roof and comfortable additional rooms. And in order for the result of the work to please the owner and household, you need to know according to what rules the truss system of the attic roof is built, in what way it is easier and better to arrange it.

At the mention of mansard roofs, we instantly recall a pentagonal gable structure of impressive size over a log house, concrete or brick walls. Visual memory suggests that its slopes must certainly have a slope of different sizes, i.e. the bottom of the roof simply has to be much steeper than the top. Due to the difference in the angles of inclination, a convex fracture is formed, which gave the roof the popular name "broken". The term has rightfully migrated to technical definitions attic structures. It reflects the essence of the usual standard in the device, but often has nothing to do with the configuration. Despite the fact that the design of all mansard roofs necessarily includes two parts, visually their presence cannot always be determined.

Purely by external indicators, the predominant number of attic structures can be divided into:

Triangular roofs, the lower and upper parts of which have an equivalent slope. Outwardly, they resemble traditional gable structures without kinks in the plane of the slopes.
Pentagonal roofs with slopes having convex corners. This category clearly shows the presence of two docked parts in the design.

In both of these varieties, the truss system consists of two tiers stacked on top of each other. The lower structure forms usable space residential attic with a height of 2 to 2.5 m, so that it was not difficult to move inside it. The second tier creates the shape of the top of the roof, it is allowed to be of arbitrary height.

By varying the angle of inclination of the upper and lower rafter legs, you can get the roof shape that is optimal in your own opinion. It is believed that a pentagonal attic looks best, the corners of which are in contact with an imaginary circle.

Note that the principle of building a broken roof is suitable not only for gable truss systems. By interpreting the basic method, the attic can be arranged in hip, shed, tent and other roof structures.

Sometimes an existing structure is remodeled into an attic, in the construction of which “broken” technology was not used. However, these roofs a priori cannot be attributed to the attic category. True, with sufficient power of the rafter legs, no one bothers to use the crossbars of the pitched truss systems as ceiling beams, and the supports of additional runs as a beam for attic sheathing.

Found out that main feature mansard roof is the presence of two adjacent truss structures connected in a triangle or pentagon of a nice shape to the owner. In their construction, typical ones are used:

Layered, according to which the lower tier of the attic is built and used in the device of the upper part.
Hanging. In accordance with it, only the upper part of the structure is built.

If, for simplicity, the section of the mansard roof is divided into two halves, a trapezoid will be obtained below, and a triangle at the top. The inclined sides of the trapezoid are allowed to be exclusively layered, and the sides of the triangle are layered and hanging.

Basic schemes of truss systems

The "classic of the genre" is rightfully considered a pentagonal scheme truss system mansard roof with struts-supports forming the walls of the interior. Its section is conditionally divided into the simplest geometric shapes. In the center is a rectangle, on the sides of which there are two mirror-image right-angled triangles, on top is an equilateral triangle.

Standard attic design

The rafters of the lower part of the structure rest on the Mauerlat below, and with the upper heel on the right or left run. Part of the frame of the mansard roof, crowning the structure, is made by hanging truss arches. They are supplemented with a hanging headstock in the middle if they are intended to cover a span of more than 3m. The headstock cannot be connected to the arch tightening with a notch, like a support post. Her job is to prevent sagging of the puff - this is not a support, but a suspension.

Supports-racks of the layered rafters of the lower part are supported through the bed on the ceiling. If necessary, to increase the stability under the props, struts are mounted. Racks are connected with bedding and girders by cuts, the junctions are duplicated metal corners and toothed plates. If the floor is concrete, it is laid under the bed bituminous waterproofing. The bed can be laid not on the floor, but on brick posts or leveling boards. When arranging an attic hardwood floor you can generally do without the bed and embed the racks directly into the beams.

The rather steep lower parts of the mansard roof slopes are practically not affected by the snow load, because precipitation does not linger on them. However, steeply installed rafters have another problem - gusty winds will tend to turn over and tear off the roof. Therefore, fastening the system to the Mauerlat must be taken very seriously. In the attic situation, each rafter is tied to the walls with twists, and not through one, as in conventional pitched structures.

The way to take out the rafters for the wall line

It often happens that the planned attic structure forms too narrow inner space. It can be expanded by extending the rafter legs outside the walls. Those. the rafter leg will rest not on the Mauerlat, but on the beams of the upper floor. This case, in theory, does not need a Mauerlat at all. But reinforcing struts in the scheme with the removal of rafters are used without question, because there is no support at all under the extreme part of the side triangles.

The Mauerlat installation can be abolished, but pouring a monolithic reinforced concrete belt for attaching beams to brick walls is highly desirable. Floor beams are attached to the monolithic belt with anchors, support posts are cut into them by a maximum of 1/3 of the beam thickness. Important point: the removal of the rafters from the wall is simply obliged to form a cornice for wooden houses at least 0.5 m wide, for concrete and stone at least 0.4 m.

Technology for the construction of a truss structure with the removal of the rafter leg beyond the wall:

We install the extreme floor beams that define the contour of the cornice overhangs. Because the ceiling will be loaded, the cross section of the beams is taken from 150 × 200 mm. If, when laying the starting beam, it turns out that the walls do not form a perfect rectangle, we strive to correct the flaws by changing the position of the beams.
On the laces stretched between the fixed extreme beams, we lay and fix the remaining bars. We control the height and step of laying the beams before fastening. The distance between the floor elements is equal to the step between the rafter legs. For insulated roofs optimal step installation of rafters 0.6m, because it is equal to the width. If the rafters are mounted with a similar frequency, they can be made from a 50x150mm board.
From the left and right edges, set aside a distance equal to the length of the short leg right triangle. At the marked points, carefully select the nests with a chisel to a third of the height of the beam under the extreme supports.
Let's make supports by cutting out spikes. They need to be made according to the size of the selected nests. For the manufacture of corner supports, a bar with a section of 100 × 150 mm is suitable, and two bearing supports for the gable sides of the roof should be made from it. Under ordinary racks, a beam of 50 × 100 mm is sufficient. The material for the support elements should be longer than the design height by the length of the tenon, but better by 10 cm in case of errors when stacking.
We install the corner posts and fasten them with temporary struts. We connect the racks with a cord.
Using a cord with a plumb line, we align the points for sampling sockets for ordinary supports in the beams and select the indicated holes.
We install ordinary racks and two bearing supports in the centers of the attic gables.
We lay runs on the installed supports - boards with a section of 50 × 150 mm. We fasten the runs with corners. It is not necessary to use as many nails as in the corners of the holes. Enough two or three for each plane. As a result of laying the board, the frame of the walls of the future attic is obtained.
We connect the supports installed against each other with bars, attaching them to the girders with corners. These elements will act as tensile crossbars. Therefore, for their manufacture, lumber of the 1st grade with a section of 100 × 150 mm is required. Under each installed crossbar, a temporary support from an inch 25 × 150mm is needed.
From above, we temporarily fasten the crossbars with the same inch, stepping back from the edges of the frame 20-30 cm. A temporary rare flooring of one, two or three boards is needed for ease of installation of the upper part of the truss system.
We make a template for the rafters of the lower row from an inch. To do this, we apply a blank board to the end of the run and the beam. Then we outline the lines of the grooves along which we have to cut off the excess. We try on, if necessary, trim the excess.
We make rafter legs according to the template. If there is any doubt about the impeccability of the construction, then it is better to cut only the upper groove for a start. By placing the rafter in its proper place, it will then be possible to adjust the lower groove after the fact without unwanted damage to the material.
We install the end rafter legs, which will need to be connected again with a cord.
Focusing on the lace, we mount the rafter legs of the lower tier of the attic.
Similarly, we make a template for the upper part of the truss system. In order to find the line of the upper cut, we temporarily sew a board onto the gable support.
We make a mirror counterpart for the previous template. The rafters of the upper tier will lean against each other.
Trying both templates on the roof. If everything is in order, we make the required number of upper rafters from a 50 × 150mm board using them.
We are constructing the upper tier of the truss system.
In order for the crossbars not to sag, we mount headstocks of the required size to each upper truss. We firmly sew them only to the ridge zone, the bottom should not be rigidly fixed.

Further, the rafter legs are screwed to the walls with wire bundles. Then the pediment frame is installed, along which it needs to be sheathed. At the end, the crate is mounted with a step corresponding to the characteristics roofing material.

Skeleton method

The technology differs from the previous method in that not separate supports are installed on the ceiling, but modules-blocks of the side walls of the future attic are fully prepared for fastening.

The block method of arranging the truss system allows you to optimize the construction of the mansard roof, because the construction of modular elements is carried out on the ground. In calm conditions without a sense of height, it is easier to achieve the accuracy of nodal connections.

The process of installing a block mansard roof:

According to a pre-made project, we manufacture frames for the walls of the attic. Longitudinal bars according to this method play the role of runs and beds. We lay them out together with the racks on a flat area and mark with the help of a square the nests for the supports of the side walls. We make cuts along the measured lines.
We cut spikes on the racks, the size of which must correspond to the size of the nests.
We connect the longitudinal beam with vertical posts, we get two modular frames - these are the walls of the attic.
We raise the frames up, install them in the intended place. We temporarily fix the position of the walls with spacers, then attach them to the floor beams with brackets.
With a chisel, we select nests on the edges of the beams for installing the lower row of rafters. You need to place them in one line. In order to observe the geometry, it is easier to first outline them with a chainsaw, then refine them with a chisel.
We carry out the upper truss tier of the attic on the ground, having previously tried on blanks for the installed elements. For accuracy of fitting to the end of the future roof, we temporarily nail the board so that one of its edges clearly repeats the central axis of the truss system. The base of the upper attic triangle performs the function of stretching. Its length is equal to the distance between the outer vertical planes installed frames. We select nests along the edges of the stretch, and spikes on the lower heels of the rafters.
We assemble the roof trusses of the upper tier, for reliability we mount an additional crossbar, ridge knot reinforce with a triangular wood overlay.
Until we moved to the roof, we make blanks for rafter legs. We try them on the frames laid out on the ground. It is more convenient to “cut” them in one fell swoop, grabbing a few pieces with a clamp. We cut out only the upper bevel, taking into account the fact that it will rest partly on the wall rack, partly on the stretching of the upper truss trusses.
We try on the lower rafter to the end. We draw in the area of her lower heel the shape of a spike, repeating the configuration of the nest in the beam. We cut out the spikes.
We move to the roof of the farm of the upper tier and the rafter legs of the lower tier. We mount the trusses first, attaching them to the upper wall trim with brackets, then the rafters of the lower part, attaching them to the floor beams with the same brackets.

The subsequent stages of roof construction are carried out according to standard rules. The drawings for the mansard roof, which clearly represent the structure, will be introduced in detail to the described principles of the construction of the truss system. Thanks to the production of connections by cutting in half a tree, the strength and rigidity of the frame as a whole increases, which will allow not to mount additional struts.

The disadvantage of the method is that ready-made modules quite difficult to transport to the roof. To transfer the assembled blocks there without the use of lifting equipment, a minimum of 4 people will be required.

Plank and nail truss system

Build a powerful attic over small country houses impractical, but you still want to save space in a small area. For the owners of small buildings, there is an excellent option - a light board-and-nail layered structure. The method should appeal to adherents of economy, because the whole timber is not used in the construction.

For the manufacture of each of the supporting elements, two boards are used, between which spaced pieces of the bar are installed. The bar-shaped cavity explains why the system is lightweight compared to solid counterparts. To ensure spatial rigidity, wind contractions are installed that connect the supports to the rafter legs. The crate, in turn, will contribute to the strengthening of the structure.

People's way of designing a layout

For a successful result of the work, the project is very desirable. It is not a fact that the presented drawings with dimensions are suitable for arranging a particular house. Typology in construction is now not at all welcome. If there is no documentation at all, it is better to make at least a sketch of the future roof, not forgetting the height of the ceilings in the attic room. Wherein:

Proportions should be observed, because too large an attic can turn small house into an awkward, mushroom-like building.
It must be remembered that the lower part of the mansard roof is built using layered rafter legs, and they optically underestimate the overhang and block the upper part of the high windows. There will be no tangible effect of overhanging when constructing an attic according to the scheme with the removal of rafters.
Do not forget that the height of the attic room must ensure freedom of movement. It is this landmark that is required to correctly determine the height of the racks of the attic walls.

You can choose the best proportions of the roof in a folk template-layout way. According to it, bars or boards are laid out on a flat, spacious area, repeating the contour of the building in real size. By changing the angles, moving the components, you can achieve the optimal configuration. Elements need to be fixed with nails and immediately measure the lengths of beams, rafters, puffs, racks. The resulting dimensions will help in the manufacture of templates.

Calculations and planning of the truss system under the mansard roof will be demonstrated by the video:

The basic options and diagrams of the attic truss structure given by us will help determine the choice of the optimal type of truss structure.

If you want to maximize the usable area of the house without spending fabulous money, you should definitely consider projects with an attic. Developers' experience suggests that this best way planning of economy class housing, because one square meter of living space in it costs several times cheaper than in two-story buildings. There is a misconception that the attic is suitable only for seasonal use in the warm season.

However, it is erroneous, since a well-insulated broken mansard roof perfectly retains heat in winter, its temperature regime no less comfortable than in the heated rooms on the first floor.

Even without additional thermal insulation, the attic is a kind of "air cushion" that maintains the optimum temperature inside the house.

A sloping mansard roof is considered a technically complex structure, and it is advised to entrust its construction to a professional team. However, a person familiar with roofing works on the example of traditional gable roof, is quite capable of overpowering its construction with his own hands, with the help of two auxiliary workers, assistants. The main thing to understand is that this is a process that requires a serious approach, which is reckless to start without preliminary calculations.

Varieties of mansard roofs

Attic - a heated or cold space under the roof, which is used as a living space. According to building codes, in the attic it is necessary to equip windows for natural light and ceilings of sufficient height for a person.

Rooms under the roof, in which these conditions are not met, are called the attic. The following types of roofs are suitable for the attic device:

broken roof

Installation of a mansard roof suitable for habitation provides for mandatory thermal insulation, organization of natural lighting using attic or vertical windows and forced ventilation.

Benefits of a broken structure

Of course, the attic can even be equipped by building an ordinary triangular roof with your own hands. But due to the steepness of the slopes, in order for the ceiling to learn, the height of such a roof must be very large. This is not economical, and also impractical, because a roof with a variable angle of slopes allows you to more effectively manage the available space.

The flatter top makes the ceilings appear higher. According to building codes, if the distance from the floor to the ridge connection is less than 2.5-2.7 meters, the room is not considered residential, it cannot be called an attic, it is rather just an attic. The sloping roof design has the following advantages:

Possibility to build higher ceilings.
High level of protection against atmospheric precipitation, wind.
Light snow removal from slopes.
Helps to keep warm.
Rational use of roof space.

Construction stages

Create a project

When drafting a broken mansard roof for do-it-yourself construction, it is better to draw up drawings with different projections, which will comprehensively show the location of its elements. Based on the length and width of the house, you need to determine the size of the attic room, as well as the roof. First of all, the geometry of the slopes is built:

In order for the project calculations to be correct, it is important to accurately make primary measurements, as well as maintain scale. Can make design easier computer programs, in which it is enough to enter the dimensions of the building and the desired type of roof, they perform the rest of the work automatically. If access to such software No, it is better to use ready-made projects.

Calculation of the truss system

Rafters are the main supporting elements of a broken mansard roof, a kind of its backbone. They are subjected to enormous loads, so they are subject to special requirements.

The choice of the section of the rafter legs is not random, but in accordance with the installation step, the distance between the supports, the values of wind and snow loads. If the first three indicators can be easily determined from the drawn up drawing, then the last two need special explanation.

The territory of Russia is divided into 8 zones with different snow load. For each specific roof, this value is adjusted by the angle of inclination of its slopes. Since the slope of the slopes is different, two indicators are calculated, respectively, the upper and lower rafters can have a different section.
There is also zoning for wind load, which also includes 8 zones. With the help of a coefficient that takes into account the height of the building, amendments are made to the tabular value of this indicator.
The values of these two indicators are summed to determine the total load. Round numbers should be big side to provide a small margin of safety. Based on them, according to the reference tables, the required section of the boards is determined.

Mauerlat installation

The beginning of work on the equipment of a broken mansard roof - the installation of a mauerlat, a durable beam measuring 100x100 mm or 150x150 mm. It is fixed at the end of the side outer walls.

Its main task is to distribute the weight of the roof structure, transfer it to the foundation, as well as protect the slopes from tipping over. Mauerlat is laid on the upper part of the wall along a pre-laid waterproofing, which is used as a roofing material folded in half or several layers of a special film.

Fastening is carried out using metal studs, they must be placed in a concrete screed. If we are talking about the reconstruction of the roof with our own hands, it is mounted with anchor bolts to the wall to a depth of 15-17 cm.

For timber and log houses use wooden dowels. Please note that the installation is flush.

Assembling the truss system

Assembly truss system of a broken mansard roof happens in the following order:

The fulfillment of the above points forms one roof truss. In the same way, the rest are installed in increments of 60-120 cm.

Waterproofing and roofing

When the do-it-yourself installation work is completed, you need to organize its waterproofing. For this you need waterproofing film or a membrane, which is usually produced in roll form.

Fasteners are selected depending on the type of material. For tiles, galvanized self-tapping screws with rubber heads are used, which are deformed in the process of twisting in such a way that they waterproof the hole.

In order to speed up the process, you can use a screwdriver. Shinglas or ondulin is fixed with nails 100 mm long. After finishing roofing works gables and overhangs of a mansard sloping roof are made out.

Summing up, we can say that a broken mansard roof will help to expand the area of \u200b\u200bthe house with your own hands. You can build it with your own hands, however, this will require special skills and costs, which, no doubt, will pay for themselves.

Video instruction

The device of the attic in an individual house is a fairly common phenomenon. This construction method reduces the cost square meter and create a rather interesting room in the roof space. To perform the device correctly attic floor, it is necessary to study the basic requirements for it and choose the right type of roof and its slope.

What is an attic

According to regulatory documents, the attic floor is the volume under the roof, which is used to accommodate residential and utility rooms. At the same time, the height of the outer walls should be no more than 1.5 m in the general case, otherwise the space will be considered a full-fledged residential floor.

A do-it-yourself attic is beneficial both during construction and during the operation of a private house. In the first case, costs are reduced due to the fact that the height of the vertical enclosing structures is reduced. The roof takes on this function without ceasing to fulfill its original purpose.

An attic is an under-roof space that can be equipped as a separate room for living.

In operation, cost savings can be as follows:

Decreased space to be heated, consequently, there is a reduction in heating costs, which are an impressive item in the cost of utilities.
After the construction is completed, the house must be measured by specialists from the BTI, after which a passport of the object is issued. It is on the basis of the area values \u200b\u200bgiven in it that taxes are charged and utility bills are paid (provided that they are connected to centralized systems and there are no metering devices, which is now practically not found). The area of the attic floor is included in the area of the whole house with coefficients of 0.7 or 0.8, depending on the height of the outer wall and the angle of the roof, which allows significant savings throughout the entire life of the facility.

Preparatory stage

It is worth starting construction with the development of a project or diagrams on which it will be drawn future design. Most often, the roof that is used for the attic floor is gable, but it is also possible to use a hip four-pitched roof. double slope design allows you to provide full-fledged windows in the gables.

In the case of using a hip to illuminate the premises, it is possible to install only attic window openings. This option can become more time consuming in terms of installing roof elements and developing interiors. Cost savings hip roof achieved due to the absence of gables (especially savings will be noticeable in brick house, where the cost of materials and the installation of wall fencing is quite high).

Do-it-yourself attic construction begins with determining the geometric dimensions and shapes of the roof. Earlier it was already said about the choice of the type of rafter system at home (gable, hip), after which it will be necessary to decide whether the slope will be straight or broken. The broken structure has such disadvantages as increased cost and labor intensity. Its use is justified by the need to increase the height of the room by changing the angle of the roof.

At the design stage, determine optimal slope roofs. Its choice depends on ergonomic considerations and the roofing material used, which imposes limitations.

Before making an attic, it is also necessary to calculate all its load-bearing elements for strength and bending, select the composition of the roof pie, perform thermal engineering calculations and decide on the materials. More on this later.

Main bearing elements

The design includes the following components:

rafter legs, which transfer the load from the weight of the roofing and the wall to the walls of the house. The section is selected depending on the angle of inclination, span, step and design load. A professional can correctly perform a detailed calculation. For private construction, approximate values \u200b\u200bcan be used, while it is best to provide a small margin.
Narozhniki- these are rafter legs, which, on one or both sides, are supported by slanted ones. The cross section is calculated in the same way as for rafters.
Slanted legs- a design that is used in a hip roof. This element serves as a support for the sprigs. The cross section is taken depending on the load and the span, in any case it should be larger than that of the rafter legs.
Mauerlat- an element that serves as a support for the stops and transfers the load from the roof to the walls, evenly distributing it. It will be correct to choose a section with dimensions of 100 by 100 or 150 by 150, depending on the complexity of the object. Mounting of the Mauerlat is not carried out during the construction of frame and wooden houses, since in this case we play the upper crown of the walls or the strapping in its role.
Rigel- a beam, which is also a support for the rafters, but already in the upper part. The crossbar is installed in the ridge of the roof or at the break of the slope, in case of a broken structure. The cross section should be taken depending on the conditions, as a recommended value, dimensions of 200 by 200 mm can be given.
Struts, racks, fights- additional elements for unfastening elements. Used to reduce cross section load-bearing structures. Their cross section is most often chosen constructively. At the same time, it is important to take into account the convenience of making connections.

mansard roof with their own hands should be built starting precisely with the selection of sections of all elements of the roof frame. The material for manufacturing is selected taking into account the following conditions:

wood should be conifers(pine, spruce, larch);
material grade - first or second;
humidity not more than 15%.

Be sure to treat all boards and bars with antiseptic compounds before starting construction.

Thermal engineering calculations

To keep the heat in the house, you will need to choose the thickness of the insulation. Most often, mineral wool is used for attic rooms (more often in slabs than in mats). It is also possible to use polyurethane foam, polystyrene foam, extruded polystyrene foam and ecowool. Having determined what to make the heat-insulating layer from, select its thickness. It is important to consider the height of the rafters. It must always be equal to or greater than the thickness of the thermal insulation. For mineral wool will also need to provide ventilation gap 50 mm thick between the upper surface of the heat insulator and the roofing. If the cross section of the rafters is small, then in order to fulfill this requirement, a counter-lattice is installed.

Before you build a mansard roof with your own hands, you can calculate it according to heat engineering manually, guided by the joint venture " Thermal protection buildings." But it is better to turn to special programs for help. In order to correctly calculate the thickness in the Teremok program (freely available on the network), you need to know the thermal conductivity of the insulation and the area of \u200b\u200bconstruction of the house, the program will find the rest itself.

A do-it-yourself mansard roof differs from a conventional pitched roof only in the presence of thermal insulation. More layers are also added to the cake to protect the insulation. Below step-by-step instruction will allow you to correctly install the elements of the mansard roof.

The procedure is as follows:

fastening the Mauerlat to the wall;
installation of rafters and systems of struts and racks;
installation of waterproofing and wind protection;
crate;
roofing;
warming;
bottom trim.

Assembling the roof frame

Installation begins with a Mauerlat. It is laid on the inner grant of the outer wall. Fastening depends on the material of the load-bearing walls, but in general it can be done in several ways:

on staples;
on studs;
on the anchor.

For fragile materials of the walls of the house, such as aerated concrete and foam concrete, a monolithic belt is made along the edge, which will prevent the destruction of the walls. Mauerlat is not provided for wooden and frame houses.

Next, you need to install the crossbars, if any. After being laid support structures, lay out the rafter legs. The fastening of the rafters to the Mauerlat can be rigid and articulated. It is better to do it with the use of cutting and fixing with metal corners on both sides.

This is a fairly old album, so nails are used as fasteners in all the drawings in it. It is better to replace them with studs. The design of the roof of the house in this normative document shown in great detail, so it is recommended that you familiarize yourself with it before starting work.

Before starting the installation of insulation in the house, it is necessary to ensure its protection from negative impacts environment. To do this, a moisture-windproof membrane is spread over the surface and the crate is fixed. After that, the roofing is mounted, taking into account the recommendations for the selected material. For example, for shingles you need a solid crate, which is most often made of moisture-resistant plywood.

Installation of thermal insulation

To perform the insulation of the house, you need to install a heater without gaps and cracks. For mineral wool, it will be easier to install if the distance between the rafters is 580 or 1180 mm clean. This will allow you to lay the material with a slight expansion, which will prevent cracks.

When using expanded polystyrene, the distance between the plates and rafters is filled with sealant or mounting foam.

After laying the insulation, you need to fix the vapor barrier to it from below. After that, the lower crate and ceiling lining are mounted. For the attic, sheathing with two layers of drywall 12.5 mm thick along the frame is best suited, followed by finishing.

The attic is the room in your house that can carry the most diverse functional load: from a workshop and an office, to a bedroom and a living room. The arrangement of the attic will cost you much less than a full-fledged second floor. And the technology of its construction is more accessible for execution.
In this article, we will consider the types of attics, as well as the stages of building an attic with your own hands.

The attic is a room bounded from below interfloor overlap, and on top and on the sides with roof slopes. Depending on the shape of the attic slopes, there can be:

single-level symmetrical with gable roof(a, b);
single-level symmetrical with a sloping roof (c);
single-level asymmetric (d);
two-level asymmetric (d).

Roof truss structures

If it is not there, or the distance of the wall from the edge of the attic is more than 7 m, hanging-type rafters are mounted. They are made up of the upper part of the roof slope, and are limited below ceiling beams attic.
Installation of the truss system is the first stage in the construction of the attic. Therefore, before starting its installation, it is necessary to calculate and take into account all the subtleties of this construction. For example, the possibility of arranging an attic floor instead of an existing one attic space, will depend on the quality of the underlying surface, on the type of foundation and its bearing capacity, as well as the state of the entire building as a whole.

However, first you need to familiarize yourself with the terminology presented on the construction drawings.

Stages of construction of the truss frame

First, the upper bar is laid, which can be a section of 0.1x0.1 m, and preferably 0.15x0.15 m. It is attached to the racks with special nails, iron staples or self-tapping screws. This bar is a rafter frame.

We make installation of Mauerlat. It is this element that is the "foundation" of the entire roof. It prevents the roof from tipping over in strong gusty winds, and also shifts the load from the attic to bearing walls Houses. For mounting the power plate, use: boards (thickness not less than 5 cm) and bars (with a minimum section of 10x15 cm). The bars are laid out along the perimeter of the entire roof and attached to the wall with long self-tapping screws or metal brackets (or better, both at the same time).
Another method of attaching the Mauerlat to the wall will not be superfluous - using a thick wire, which is pre-mounted in the top row of the brickwork of the wall. Remember that the stronger you tie the Mauerlat and the wall, the stronger the entire attic structure will be. And one more thing: under the Mauerlat bars, it is necessary to lay a layer of a waterproofing agent, and treat the boards or bars themselves with an antiseptic and waterproofing impregnation.
, which are most often purchased ready-made (although you can make them yourself if you wish). Before mounting these structural elements, it is necessary to put marks on the Mauerlat that will indicate the place where the legs are attached (the accepted distance between the legs is 15 cm). Labeling will simplify and speed up the implementation of this step.
We lay the edge rafters to the pediment. Particular attention should be paid to the fact that the edge of the front and the top of the rafters should be in one line. In addition, pay attention to the quality of the board used for the rafters: it should be without any special defects (normally no more than 3 flaws per 1 m), thickness - about 4 cm, width - about 15 cm. After the edge rafters are installed, they are connected by a level rope, along which all the other rafter legs are mounted.
It's time to bring all the straps together. This is done by top point all rafters with a run. Then the ridge beam is installed, which, in principle, is not an obligatory element of the frame (it is erected when the roof is longer than 7 m).
Do not forget that at the stage of erecting the truss structure, you need to lay window frames under the roof windows.
If the roof is lower than 7 m, then extensions are mounted in the upper part of the rafters, which perform a dual function: they serve as ceiling beams for the future attic, strengthen the frame of the attic roof.

The rafter system is ready. It remains only to make a crate, fix the hydro-barrier material, lay a layer insulation material, as well as roofing. Mansard roof is ready. We proceed to the internal work, which we will discuss below.

The importance of insulating mansard roofs is undeniable, because. the walls of the attic room are united with the mansard roof, or as close as possible to it. Because of this, the attic room freezes faster in winter, and heats up significantly in summer.

Mineral wool is laid in the space between the rafters. In this regard, the base sheets of insulation are cut to the size of the gaps between the rafters. Sheets of mineral wool are laid on a pre-laid layer of vapor barrier, and a layer of hydro vapor barrier is attached on top of the sheets. In this multilayer structure, air gaps are formed, located between the layers of a vapor barrier-mineral wool and mineral wool - a hydro vapor barrier. These air channels will subsequently contribute to the ventilation of the entire structure, and therefore they must be brought open in the ridge area. This will improve the quality of the insulation.

When insulating the attic, remember that the microclimate of the attic room and the comfort of your stay there will depend on the quality of insulation and the availability of ventilation.