Water pipes

How to build a gable mansard roof. How to make a broken mansard roof with your own hands

Use the entire possible area, give the house originality and significantly reduce heat loss through the roof - these are the tasks that the attic solves. If there is a certain margin of safety at the foundation, in this way you can turn cottage into two levels. It is also attractive that a do-it-yourself mansard roof can be built even without special building skills. It is important not to make a mistake with the choice of materials and do everything according to the rules.

Windows in the usual floor are located in the walls. There are no or almost no walls in the attics. Roofing replaces them. That is why windows are made special: they not only have to let in enough light, but also withstand wind and snow loads, which are much more on the roof than on the walls.

Skylights

When planning an attic, it is worth considering the recommendations of SNiP. They recommend that the window area be at least 10% of the floor area. So if the attic is divided into several rooms, each should have a window.

Of all the methods shown in the photo for arranging skylights with an attic, it is the easiest to implement inclined installation. At the same time, it is necessary to ensure the proper degree of waterproofing of the junction, as well as to use special models with a reinforced frame and reinforced glass - the load on the surface can be significant.

Benefits of a sloped roof window:

more light, not so sharp borders of light and shadow;
the roof surface remains flat, its relief is not complicated;
relatively easy installation.

When planning such a window, it must be remembered that its area increases with an increase in the angle of inclination. At what height is it more convenient to install such a window and how its height in centimeters increases depending on the slope, see the photo.

The steeper the slope relative to the floor, the lower the height of the window should be.

The width of the window frame should be 4-6 cm less than the pitch between the rafters. Then it can be easily installed without disturbing the structure of the frame. If the window is wider, it is necessary to make a reinforced beam above it, calculate the load.

If you need to have a larger window, it is easier to put two narrow ones side by side. They look no worse than one big one, and there will be fewer problems.

When installing a dormer window, the geometry of the roof becomes more complicated: a valley appears on top and on the sides. Because of this, the truss system becomes more complex in both planning and assembly. The complexity of laying roofing also increases. All valleys are the places where leaks are most likely to occur. That is why it is necessary to do everything very carefully. In regions with big amount snow, it is advisable to install snow retainers above such windows: so that they are not blown away during a sharp descent.

The device of a vertical window-dormer in the mansard roof

The advantage of such a window: near it you can stand in full growth. But they let in less light, the terrain becomes more difficult and the roof becomes more problematic.

A recessed window is usually used if an exit to a balcony is made through it. In other cases, this method of device is not the best way: little light enters, the shadows are very deep, which is tiring for the eye, the geometry also becomes more complicated, although not to the same extent as in the previous version.

The easiest way is to make a window in the end part of the attic. In this case, a reinforced frame or reinforced glass is not needed. Quite simply high-quality glasses are enough. It is this option that can most often be seen in country attics: this is the most inexpensive option, which is easily implemented with your own hands.

truss system

At self construction private houses with an attic usually choose a sloping roof. It allows you to get a room of a significant area, larger than under the gable.

With an equal width of the base (house), the attic room under a sloping roof is larger than under a conventional gable. The truss system is getting more complicated, but a gable roof with an attic under a sloping roof is still more popular.

The design of the sloping mansard roof is such that the overhangs can be lowered quite low, giving the house an interesting look. But the long overhang of the roof is not only a decorative role. They also cover the upper part of the wall from precipitation and divert the bulk of the water away from the foundation. Although when planning, you need to keep in mind that in strong winds they increase the windage. Because of this, it is necessary to use more powerful boards and beams. Therefore, the size of the roof overhang is chosen based on several considerations, the main of which is weather conditions.

Tilt angle

It depends on the roofing material, but most of all - on the region and weather conditions. The classic version is shown in the figure: the lower slopes in relation to the plane of the attic floor are inclined by 60 °, the upper ones by 30 °. Based on these data and the parameters of your building, all lengths can be calculated. Just keep in mind that according to SNiP, the ceiling height in the attic cannot be less than 2 m. Then, by definition, this is an attic. A person will feel comfortable if the ceiling is raised to a height of at least 2.2-2.3 m. Based on this, according to the rules of geometry, calculate the required lengths.

At classic version rain load on side surfaces may not be taken into account. Precipitation can only be held on the upper part, the angle of inclination of which is less than 45 °.

In general, the slope of the side surfaces usually ranges between 45° and up to 80°. The steeper the slope, the greater the windage it has, this must be taken into account: in regions with strong winds, it is better to make flatter roofs. Then the wind loads will be perceived much better.

Types of rafter systems of broken roofs

The design of a broken mansard roof is one of the options truss system(The most common)

For making a frame broken roof do-it-yourself most often use pine lumber, grade - not lower than 2. The choice of the section of timber and boards depends on the size of the roof, the selected roofing (its weight), wind and snow load in the region, the installation step of the rafters. All these parameters are taken into account in the calculation. The technique is prescribed in SNiP 2.08.01-89 and TCP 45-5.05-146-2009.

One of the options for building a frame with hanging rafters

Above in the figure is a drawing of a frame with hanging rafters. It can only be implemented if the base of the upper triangle is no more than 4.5 meters (in this case, this is the width of the attic room). If more, you will have to make layered rafters, which should rest on the load-bearing wall in the middle (the attic will turn out to be divided into two parts by a row of beams).

Another version of the upper part is shown in the photo below (the picture is clickable). In this case, the side rafters are reinforced with struts. They significantly increase the rigidity of the system.

There is a second way to achieve a similar effect - to set contractions - in the figure they are only outlined with barely visible lines. The length of the side rafter leg is divided into three, contractions are set in these places. They will be needed if the roofing will have a solid weight.

A variant of the rafter system of a sloping roof - with struts that increase the rigidity of the system

For a building that is small in size, the roof frame can be generally simple: at the top there are two hanging rafter legs, a puff, floor beams, racks and side rafters (pictured below).

The device of the truss system of a broken mansard roof for small house

How to calculate a sloping roof

The mansard sloping roof of a small house (width no more than 6-7 meters) has been built so many times that, based on experience, we can say what materials should be used. Many parameters are dependent on other materials. For example, the installation step of the rafters is tied to the parameters of the insulation. To ensure that there is as little waste as possible during insulation, installation is easier, it is necessary that the distance from one rack to another is slightly less than the width of the insulation (by 20-30 mm). So, if you are going to use mineral wool, its width is 60 cm. Then the racks must be installed so that the clearance between two adjacent ones is 57-58 cm and no more.

The width of the board for the rafter leg is again determined based on the insulation. For the central zone of Russia, the required thickness of basalt wool is 200-250 mm. That's not all. In order for the thermal insulation to dry out, a ventilation gap of 20-30 mm is required (without it, the condensate will gradually rot the wood and render the mineral wool unusable). In total, it turns out that at a minimum the width of the rafter leg should be 230 mm. The thickness of the board is at least 50 mm. This is in regions with mild winds and not very heavy snowfalls. Summing up, for all rafters - ridge and side - a board of 230 * 50 mm is required.

If lumber with such characteristics turns out to be too expensive, it will be possible to make insulation in two directions: part along the rafters, part, stuffing the crate, across. You can lay a minimum of 100 mm of basalt wool, therefore, you can take a standard board 50 * 150 mm and leave it on the ventilation gap of 50 mm, or order a non-standard 130 * 50 mm. See what is more profitable in terms of money.

For racks and beams, it is better to take a beam of at least 80 * 80 mm, better - 100 * 100 mm. Especially in areas with difficult weather conditions - with heavy snowfalls or strong winds.

For a more accurate estimate, ask the experts. This is a long process, consisting of the collection of loads from the roofing material, the structural elements themselves, wind and snow loads. After that, according to a certain formula, the elements are selected. For more information on how the calculation is carried out, see the following video.

Do-it-yourself mansard roof: installation procedure

The Mauerlat device on mansard roofs is no different from the standard version. If or logs, you can use the upper crown as a Mauerlat. It is only pre-treated with impregnation with high protective properties.

If the wall is made of foam blocks, a reinforced monolithic belt. On the brick wall or folded from shell rock, other similar materials, the device of such a belt is optional. Waterproofing is laid on the wall in two layers, and on top - a timber treated with an antiseptic - 150 * 150 mm or a log. It is fixed with embedded studs.

When assembling all elements, long nails are used - at least 150 mm long. In the most critical places, it is better to connect three or more elements with bolts or studs with double-sided threads. It is desirable to strengthen all joints with steel plates or corners.

First way

The installation of mansard roof rafters is done in two ways. First: parts are assembled on the ground, then they are lifted up in finished form. There, the first to expose the extreme structures that will become the gables. They are placed vertically, fixed. It is often more convenient to fix them with long bars nailed to the wall (temporary). The following assembled structures are inserted into the prepared recesses in the Mauerlat (they are made with the required step). They are set strictly vertically, carefully fixed. If necessary, install additional temporary spacers that fix them in the desired position. Side rails are installed.

How to build a sloping roof in this way, collect nodes, see the video below.

Second way

The second method - the construction of a sloping roof is carried out by sequentially collecting elements right on the spot. This method is more convenient if the structure is large and when assembled it can only be lifted using special equipment (crane).

First, floor beams are laid. Racks and puffs are attached to them, temporary struts are placed to hold them in the vertical direction. Next, the rafters of the upper and side legs are assembled, puffs and jibs are installed.

During installation, the following sequence of actions is observed: first, the extreme elements are installed and set in the desired position, securely fixed. If necessary, use temporary spacers. Between them, a fishing line, rope, lace is stretched, which will serve as a guide for the installation of all subsequent elements. This simple move allows you to get the perfect geometry (do not forget to check the slope angle, verticality or horizontality).

Puffs are attached over the racks - bars, to which the side rafters are then fixed and on which the puff of the upper triangle is installed. Puffs are attached with metal corners. Since the beams are long, they sag. This is further eliminated - after the installation of the upper rafter legs - using vertical beams of a fixed or adjustable height. And temporarily they can be propped up with racks (so as not to pull the entire system).

To make it easier to maintain the desired angle when installing the side rafter legs, templates are made according to which the cuts are made. But since the geometry of DIY buildings is rarely perfect, adjustments may be needed. To check the resulting angle of inclination from several boards, another template is knocked down, which checks the correct installation.

If the standard length of lumber - 6 meters - is not enough, or order the required length ( expensive pleasure) or increase. When building up, two boards with a size of at least 0.6 meters (30 cm on each side of the junction) are nailed to the junction. They are nailed on both sides or bolts are used.

A reliable way to build rafters. The length of the "patch" - at least 60 cm

After installing the side rafters, it remains to install the top ones. A template is also made for them, it is first sawn on the ground, and installed at the top.

The top part can be done in different ways. Its structure depends on the width of the base. See the photo below for how to make it.

Since the device of the mansard sloping roof does not provide for the presence of a ridge, a beam is stuffed into the puff in the middle, to which the slopes are attached, fixing the triangle in the required position.

Nodes and their drawings

When installing the truss system, questions may arise regarding the assembly of nodes - the intersection and connection of several structural elements. In the photo you see drawings of key connections.

The second option is to connect the side rafters and the upper triangle. Bolts are used for more secure fastening.

How to make a do-it-yourself fastening of the upper triangle and rafter leg on a mansard roof

The methods for attaching the rafter legs to the Mauerlat or, as in this case, to the side beam are shown in the figure below. To make it easier to mount a heavy element, a stop board (bar) is nailed to the rafter from below, which limits its movement: the board rests against the edge and prevents it from sinking lower.

The attic is a great opportunity to increase the total and useful area of the house. It settles down in the attic and is quite habitable, provided that it is designed correctly. The mansard roof truss system, the drawings of which can be found in this material, is the basis of the entire structure. And it is she who needs to be given the closest attention when designing.

Mansard roof truss system - drawings

An attic is a room that is located directly under the roof. Its facade is partially or completely formed by roof surfaces (according to SNiP 2.08.01-89).

SNiP 2.08.01-89. Residential buildings. Download file (click on the link to open the PDF file in a new window).

It is a full-fledged residential floor; there may be one or more rooms, depending on the design parameters.

On a note! The word "attic" comes from France. It was the French architect who in 1630 came up with the idea of usefully equipping attic spaces. And this man's name was Francois Mansart - hence the name of this type of superstructure appeared.

The peculiarities of mansard roofs are not only the special design of the truss system, but also the need for detailed consideration of other aspects - insulation, moisture and vapor barrier, etc. Since, due to the attic, the load on the foundation and walls of the building itself usually increases, then mainly all of it elements are built from lightweight materials. That is, to create a truss system, it is recommended to use wood; light material options are used as a heater.

The attic can be of impressive size and occupy the entire area of the building, but within its walls. Sometimes it settles down only on part of the ceiling, and then the back covers the usual roof.

Very often the attic is used in individual construction, because this is an opportunity to increase the living space of the house, to make it warmer (heat loss through the roof is reduced by an average of 7-9%). And the cost of arranging the attic will be much less than the construction of a full-fledged floor.

In general, building an attic is not very difficult and you can cope with the task yourself. The main thing is to correctly calculate the wind, snow and other types of load.

Bar prices

Types of attics

The design of the attic will directly depend on what form it is supposed to equip the roof. After all, part of the walls of this room will be formed just by the slopes of the roof. Depending on this, there are several types of mansard roofs.

Perhaps the easiest option for arranging the roof itself and the attic floor directly. This roof has only one slope, which rests on the multi-level walls of the building. Thus, the slope angle is formed. By the way, it should not go beyond strictly limited limits - 35-45 degrees (if the slope is less, then snow will constantly accumulate on the roof in winter time, which will significantly increase the load on the entire house and will cause the installation of additional supports in an already small attic). The truss system here is extremely simple.

On a note! The construction of the rafters will not need additional supports if the distance between two walls located opposite each other does not exceed 4.5 m.

Such mansard roofs look original, despite the simplicity of their design. Usually, from the side of the high wall of the attic, quite big window which allows you to get a well-lit room.

Mansard roof with two slopes

This option is also relatively simple in execution and due to this it is widely distributed as much as possible. The main thing is that the height of the roof itself allows you to equip a living space under it. The truss system of this roof looks like that of a conventional gable roof, it can be asymmetrical or symmetrical, depending on the location of the ridge.

Gables, as a rule, are simple and straight, and the room inside will have the shape of a trapezoid or a square (the latter option is possible only if attic space spacious enough). The height of the ceilings near the walls should not be more than 1.5 m, the sloping cone-shaped ceiling goes higher.

The main disadvantage of a gable roof in terms of attic arrangement is the loss of most of the free space. That is, the lion's share of the room is cut off by the roof slopes. Of course, this free space is usually used as a warehouse, but this aspect affects the size of the attic very significantly.

Broken mansard roofs

In fact, this is also a kind of gable roof, but its slopes have, as it were, two parts located at different angles relative to the ceilings. Due to this, you can get a fairly spacious attic floor, which in terms of area will be equal to almost a full-fledged second floor (it will be less than the lower floor by only 15%). The height from ceiling to floor will be the same throughout the attic and will be about 2.2-2.3 m.

mansard roof broken line - drawing

However, this design implies the construction of a rather complex truss system. And not every novice master can cope with this task. However, despite this, the variant of a broken roof is quite common.

Roofs are four-pitched (hip) mansard

Such a roof involves the creation of the most complex type of rafter system, which requires the most accurate and painstaking calculations. The surface of the roof itself will have a fairly large area, because of which you will have to spend a lot of money on other materials - insulation, hydro and vapor barrier films etc. But in general, the attic turns out to be quite spacious, even though parts of the usable area are cut off from it.

But such a roof has maximum resistance to snow and wind loads. Overhangs can be large enough and will be ready to protect the walls of the building from the effects of precipitation. Such mansard roofs look very attractive.

Attention! When arranging a hipped roof, it is important to take care of the need to strengthen the layered rafters - it is they who experience the maximum load.

Roof truss system

When arranging mansard roof the truss system can be made from elements of a layered or hanging type. In the first version, the rafters are installed so that they form a triangle with even edges. In this case, the support is carried out on the Mauerlat, fixed along the perimeter of the walls, on additional supports installed under the rafters, and the junction of two boards in the ridge area also serves as a reference point.

When installing rafters of a hanging type, supports in the form of additional beams are not provided. They rely only on the walls of the house. Drawstrings may be used. The rafters themselves in this case work on bending and compression.

Hanging and layered rafters - an example of a drawing

Creating a rafter system during the construction of the attic is a paramount task. It is first important to correctly calculate it and take into account all the subtleties of its construction. To understand what will be discussed, you need to familiarize yourself with its main elements.

Table. The main details of the rafter system.

Element	Description
Mauerlat	This is a bar (or board), which is fixed on the upper end part bearing wall buildings. Rafter legs will be attached to it. It plays the role of a support and will transfer the entire load from the roof to the walls of the building.
Rack	Any vertically located beam that acts as a support for rafter legs.
Overlappings	This is a series of beams laid horizontally and forming the floor of the attic floor. They also play the role of the ceiling of the first floor of the building.
Rigel	These beams are located horizontally and are additional reinforcing and supporting elements for the rafters. They can also be called "puffs".
rafters	Also called "rafter legs". It is they who form the frame of the roof and give it shape. From above, moisture-proof materials, lathing and roofing will be attached to them.
crate	A lot of bars or sheets of plywood that are attached to the rafters. It is on them that the roofing material will be directly fixed.
Suspension	A board that helps distribute the load. It is installed under the crossbar or puff.
filly	The board that forms the overhang of the roof is fixed at the bottom of the rafter leg.

Prices for building boards

Building boards

Required Calculations

In order to avoid mistakes when designing an attic, it is important to carry out a number of preliminary calculations. Depending on the chosen type of truss system and the type of roof, they may differ. The easiest way is to use some special program, but you can try to do all the calculations manually.

It is important to determine the area of \u200b\u200bthe final roof, the size of the attic, the width of the floors. The calculation is based on the following data:

length and width of the house;
precipitation volumes in winter and summer (this will help determine the required angle of the roof slope);
the width of the joints between the parts of the floors.

An example of calculating the pitch of the rafters in the program "Rafters 1.1"

Consider a calculation example: the length of the house is 12 m, the width is 3 m. The amount of precipitation in the area indicates that the required angle of inclination of the roof should be about 40 degrees. The calculation is made according to the formula Hk \u003d L x tgA, where Hk is the desired height, L is ½ the width of the structure, tgA is the tangent of the angle. Total: Nl \u003d 3/2 x tg40 \u003d 1.26. This means that the recommended roof height should be 1.26 m.

On a note! Most often, when constructing mansard roofs, owners opt for broken truss systems. The methodology for calculating the parameters in this case can be found in SNiP 2.08.01-89 and TCP 45-5.05-146-2009.

More and more people are turning to self-construction of a house.

There are many reasons for this, and everyone is guided by their own motives.

But the main thing is savings, of course, subject to knowledge of the matter.

Building a house for every man should be a mandatory attribute of success.

Investing in real estate is the best thing to do. The house will stand for decades and over time its value will only increase.

Of course, much depends on the design of both the internal and external parts of the residential building.

For a quality construction, you will need to study the technology of erecting a mansard roof. Another important skill is knowledge of carpentry. Or you can study the instructions yourself, which describe in detail the entire project of work. You should also pay attention to the fact that there are various.

When starting construction, you need to be puzzled by the following questions:

What are the best materials to use when building a mansard roof?
How many work steps are to be completed?
How many people will be needed to help with the construction?
What attic do you want to build?

It is best to plan the construction of the attic, installing a gable roof with a broken line, so you can get the largest possible area of \u200b\u200bthe future room.

Before starting any construction should be developed. When working through it, take the figures indicated in the calculations seriously, even the slightest mistake can lead to future damage to both the roof itself and the walls of the house.

So how to make a mansard roof? This article will help you answer this question.

For soft roofs solid;
Discharged for slate.

Naturally there are certain installation rules soft roof , here they are:

If the pitched angle of the roof is located in the range from 5 to 10 °, then the roof has the form of a continuous flooring, special waterproof plywood or boards are used;
When the slope of the roof is between 10 and 15°, in this case the roof is made of timber with dimensions of 45 × 50 millimeters and in increments of 45 cm;
If the value of the oblique angle is greater than 15° for the crate a beam of 45 × 50 mm is used, but with a step of 600 mm;
For the skate attachment area install an additional beam.

Lathing under a soft roof

Installation of Mauerlat and truss system

Mauerlat is laid after work has been done to level the attic and place the flooring.

Due to the placement around the perimeter of the attic Mauerlat all non-straight corners can be corrected.

Beams are used as material.. The thickness is selected under the edge of the walls.

When you put the Mauerlat under the edge of the eaves, you should be especially careful.

Ensure that the structure is non-distorting, because it is impossible to enclose additional elements. You will have to disassemble part of the outer masonry of the wall and raise the inner part of the wall.

Mauerlat installation

Insulation installation

You need to insulate the attic if you are going to settle in it. First of all, it is worth deciding on the material used as. The best solution there will be special basalt slabs.

The density of the insulation is needed at least 30-40 km per cubic meter otherwise, its subsidence in the future is inevitable. And the thickness is 150 mm. Also, a special film is installed in the roof to protect it from getting wet.

Step-by-step installation of insulation

Installation of battens and counter battens

After the base is installed, it is necessary to install to strengthen the structure. This is necessary if the slope angle is large..

The counter-lattice is installed from small bars, which are superimposed on top of the main crate, already laid waterproofing layer. When installing a counter-lattice between the roof and the base, a ventilation space is formed, which allows to increase the service life.

Lathing installation

Installation of waterproofing and vapor barrier

Do-it-yourself sloping roof requires the installation of waterproofing. To protect the roof from moisture penetration between the roof and the base a special layer of roofing felt or film is laid. The counter grille helps better ventilation to get rid of the effect of vaporization.

The most common evaporative protection system is a three-layer design - a hydrobarrier.

Reinforced lattice. It is woven from polyethylene fibers.
Anticondensate or barrier barrier.

Waterproofing is installed on the rafters or crate.

Installation of waterproofing

Types of roofing materials and their installation

The market offers a wide range of roofing materials for every taste. Each of them has its own advantages and disadvantages. Any builder first of all looks at the cost of the roof, then at its quality and service life.

roofing material

Conclusion

The construction of a mansard roof requires special diligence and painstaking work if you want to get a high-quality and final result. We will have to invest a lot of effort, not only physical, but also moral.

It will take a smart approach to work so that it ends without problems. Encountering a number of obstacles, most owners turn to the help of hired workers. But on the other hand, what can bring more pleasure than not done high-quality work with your own hands.

Useful video

In this video you will learn how to assemble a mansard roof:

In contact with

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 economy class housing plans, because one square meter housing in it is several times cheaper than in two-story buildings. There is a misconception that the attic is suitable only for seasonal use in warm time of the year.

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. Nevertheless, a person who is familiar with roofing works using the example of a 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 light with the help of dormers 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. Computer programs can facilitate the design, into 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 there is no access to such software, 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 loads. 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. Numbers should be rounded up 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 concrete screed. If we are talking about the reconstruction of the roof with our own hands, it is mounted anchor bolts to the wall to a depth of 15-17 cm.

For timber, as well as log houses, wooden dowels are used. 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 truss 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. This requires a waterproofing film or membrane, which is usually produced in the form of a roll.

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

Attic premises in a country house or country house on the garden plot it is most convenient to arrange under a roof with two slopes.

uncomplicated truss construction can be done independently, without lifting mechanisms and complex tools.

Space under the traditional for wooden and brick houses gable the roof is most often used as a cold attic.

However, at low cost and well-placed roof insulation, the attic can be turned into a cozy room, bedroom, nursery, and even a living room. From choice type of room under the roof will depend

In small areas country houses construction gable roof with an attic solves the problem of shortage residential premises.

Features of a gable roof with an attic

To determine the design of a gable roof should be considered:

house layout;
Dimensions;
wall thickness;
The presence of a bearing longitudinal wall.

In addition to building factors, the choice of roof configuration is influenced by climatic features of the location of the building.

For a house with a width of up to 6 m located in a temperate climate zone, choose a gable roof with a hanging truss structure and a slope angle of at least 400 degrees.

A smaller angle of inclination will not allow you to arrange an attic room with a sufficient ceiling height. In addition, the steeper the roof, the less snow and water on it. linger. From a roof mounted at an angle to 450 degrees, snowflakes slide off under their own weight.

The principle of the truss system

load-bearing roof structure with hanging rafters does not require complex calculations and design solutions. The diagram shows that the rafters of a gable roof with an attic are installed in the form triangular arches along the entire length of the house with a step that depends on the weight of the roofing material with the sheathing and insulating materials. Frontal surfaces are a continuation of the walls of the house and are made of the same material.

Important! For an attic room, during the construction of gables, window openings are provided.

Principle hanging rafters based on spacer system. The rafter legs rest at the top point on each other and are tightened with a crossbar, which is fixed at the height of the attic ceiling. puff performed to balance the spacer load acting on the walls of the house. At the bottom, the rafters are rigidly attached to the Mauerlat - wooden foundation for roof structure roofs.

Mauerlat have along the perimeter houses, on the upper foundations of the walls. Perform such a foundation by continuous laying of timber 100 on the 150 mm or 150 on the 150 mm for waterproofing.

If the length of the beam is not enough for laying with one edge along the entire wall, it is connected from two parts in the center of the fence, driving the fasteners at an angle into 450 degrees. The Mauerlat is fixed to the base of the wall closer to its inner edge with anchor bolts and studs.

Vertical supports are attached to the Mauerlat with metal corners for installation rafter legs, on which cuts are made for a better emphasis on the Mauerlat beam.

Determination of structural dimensions

Length rafters can be determined without calculations. For this:

In the center front wall vertically installed temporary support with tied twine on the intended;
Leg-split taken to the corner of the house, thus determining slope size roofs. Add to this value 60 cm on the cornice overhang and get the size rafter beam.

Estimated dimensions of the hanging rafter structure of a gable roof for a house with a width 6 m indicated on drawing.

We define number of truss arches. For this:

Divide length buildings on distance between supports. For a small country house optimal step installation of rafters - 1m. If the length of the house is 8 m, then the number of arched structures will be:
8/1 + 1 = 9 , and the distance between them: 8/9 = 0.9 m.

Installation of the truss structure

After determining the quantity consumable, start to installation truss system of a gable mansard roof. It can be done do it yourself:

From two bars and puffs going triangular truss. If the slope of the roof is 450 degrees, then at the top point the bars rest on each other at an angle of 900 . The top connection is fixed with a metal plate. Puff-bolt fastened with self-tapping screws at the height of the proposed attic ceiling;

Advice! To increase the reliability of the design, the crossbar-puff is installed on both sides of the truss. Fastening is done with bolts.

rafter structure raise to the installation height and attached to a temporary support on the front wall. Rafter legs rest against Mauerlat washed down in places and screwed to pre-installed supports. Under the rafters enclose wooden corners;
plumb check vertical installation of the farm;
Similarly install a truss arch on the opposite front wall;
Between the tops of the extreme arches pull the twine or nailed run for the installation of intermediate farms. For better fixation of the vertical position of the arches, the rafters are temporarily fastened together with boards;
Install the skate and proceed to the crate of the truss structure.

Important! After installing the roof structure, the air ducts and chimneys should be removed from the roof.

Roof decking and waterproofing

To strengthen truss structure and creating a base for roofing material on the rafters are installed crate.

For step-by-step lathing under, corrugated board, slate or metal tiles, a coniferous board is used. Can be used 40x50, 50x50, 50x60 mm but he will make heavier roof structure.

Now consider types of waterproofing for a gable roof. For a gable roof as a hydrobarrier, it is suitable:

Bituminous rolled material- traditional, inexpensive, but short-lived roofing waterproofing;
Reinforced film- polyethylene reinforced with synthetic thread creates a waterproof barrier between the roofing material and wooden structure roofing;
waterproofing film- perforated polyethylene, which has a unique ability to pass the evaporation of moisture from the insulation, but does not let water inside;
Anti-condensation film designed to protect metal roofing materials from condensate. The outer layer of the film is made of geotextile, which perfectly absorbs moisture, and the lower polymer layer does not let water through to the wooden elements of the roof.

Start laying roll waterproofing from lower slope edges. The subsequent rows are overlapped.

Lathing installation

Installation of gable roof sheathing is a step-by-step process. The installation steps are:

The waterproofing layer is shot with galvanized brackets to the rafters with a slight sag for under-roof ventilation;
To install the battens, wooden slats are nailed to the rafters on top of the waterproofing, the lamellas of the battens are fastened with self-tapping screws;
A cornice is attached to the lower edge of the rafters;
Across 30 cm from the cornice, the next line of the crate is installed;
Rows of battens are fixed parallel to the eaves with a step 60 cm;
Connect the wooden lamellas of the crate at the intersection with the rafters;
An additional row is installed on 10 cm below the roof ridge;
Wind platbands are fixed on the end rafters;
Compare the diagonals of the roof slopes.
After the lathing of the truss structure, proceed to outer cladding roofs with roofing material.

Roofing materials and their fastening
For the top covering of a gable roof, modern roofing materials are used - ondulin, corrugated board, metal tiles.
Along with strength and durability, they are easy weight, so they are suitable for facing mansard roofs.
Roofing sheets are attached to the crate with self-tapping screws, beginning from the bottom row.
The amount of material is calculated from the area of the roof slopes with a coefficient 1,2 for lap fastening.
Before starting shelter flat surfaces, aprons made of metal of suitable thickness or special blanks are installed around chimneys and air ducts.
In conclusion roofing work fasten ridge elements and end strips.

Advice! Under the ridge cover, it is necessary to glue the sealing tape, which will prevent water from entering under the roof sheathing.
From the inside, the roof is insulated and a vapor barrier layer is laid.
Heat and vapor barrier of the gable roof of the attic room
Warming mansard roofs are made by laying a heat-insulating layer in the recesses between the rafters. Used as thermal insulation mineral wool, which has a low weight, good vapor permeability and low thermal conductivity.
To avoid getting wet mineral wool due to condensation, it is covered breathable layer of vapor barrier. perforated polyethylene films, anti-condensate multilayer coatings and diffuse membranes well cope with the task of vapor insulation of the inner surface of the roof.
Vapor barrier is laid across the rafters, along the entire length premises, with overlapping lanes for at least 10 cm. The seams are glued with a special tape. The film is shot to the rafters with staples using a stapler.
At the final stage of the device of the attic room, internal the surface of a gable roof is sheathed with sheets of plywood, drywall, clapboard or other decorative coated.
For more information on how and how to insulate the roof of the attic, read correctly.
Subject to the basic rules for the construction of a gable roof, taking into account the advice of experts on the selection and fastening of building and insulating materials, the device of the attic room is performed independently. A warm, well-ventilated attic will serve as an additional living space and improve the microclimate of the whole house.
See video about the installation of the truss system of a gable mansard roof: