Do-it-yourself installation of a sloping roof step by step instructions. How to build a sloping roof: we take into account the correctness of the technology

A broken line is called two- or hipped roof, the slopes of which are divided by additional ribs into several planes. This technique allows you to create additional usable space under the roof, where you can place an attic, or build a roof over buildings of the most complex architectural form. Most often in individual construction there are broken gable roofs, which are also called attic.

Roof design

For arranging living space under the roof, it is desirable that the width of the house be at least 6 m. This is also important for creating a strong one. Think in advance what the ratio of the parts of the slopes will be, whether there will be skylights on the roof and determine the exact location of their location. Calculate required amount roofing material, insulation, waterproofing according to the dimensions of the roof, scaffolding for rafters, as well as fasteners, create a detailed drawing or use standard project roofs.

There are special programs that allow you to calculate required size beams for truss system and the step between them, depending on the type of roofing material, that is, its weight, the amount of precipitation in winter and other parameters.

The construction of a sloping roof must be foreseen in advance, since under it, when building a house of brick, gas silicate blocks or foam concrete, it is necessary to pour a reinforcing belt. Threaded studs are preliminarily laid in it in increments of 1.5-2 meters.

materials

For rafters, you will need a high-quality timber (for legs and braces) 5 * 10 cm and an edged board with a thickness of at least 3 cm, for Mauerlat a timber of 25 * 25 cm. Coniferous wood, well dried, with a residual moisture content of at least 22%, is preferable. In general, rafters for a broken roof should be more massive than for a gable roof, which is caused by its greater weight. Calculate the beam strength.
Between themselves, the bars and boards are fastened with steel brackets and studs measuring 8-12 mm. Also at all stages you will need bolts, screws, nails and metal staples for roofing.
The lathing and counter lathing are made of wooden slats 5 * 2.5 cm. Parts cut from thick plywood are used as connecting elements.
Insulation, hydro and vapor barrier films are needed.
Roofing material for a sloping roof should not be too heavy. Suitable metal tile and metal profile, ondulin,.

Roofing work requires a standard set of carpentry tools, ladders and safety equipment.

truss system

Before assembling the rafters, all wood is treated according to the instructions with an antiseptic and impregnated with fire-fighting solutions. For better penetration, all parts of future rafters are covered twice. Before proceeding with further assembly, you need to wait until it is completely dry. At the same time, it is advisable to carry out the processing of laths for battens and counter battens. Holes are drilled in the Mauerlat bars with the same pitch as the studs are installed.

truss structure represents the sections connected by the modular principle. Each of them can be assembled on the ground, lifted up, and then already installed according to the drawing, which greatly simplifies the work. The rafters are connected to each other at a certain angle, and the geometry and reliability of the roof as a whole depend on the accuracy of the cut and compliance with the dimensions of all parts. To do this, it is convenient to use plywood or metal templates made in advance according to the project.

1-2 layers of roofing material are laid on the long walls of the house and beams for the Mauerlat are installed, which are attached to the studs with nuts. It is important that they run strictly parallel to each other, and their inner part coincides with the inner part of the walls. If the wall is thicker than the beam for the Mauerlat, then a protective row is laid out with a brick from the outside. If the house is built from timber or logs, then the Mauerlat is replaced by upper beams or logs.

Mounted on the Mauerlat with temporary struts vertical racks. First, two extreme racks are installed in a row, then a rope is pulled between them, along which the rest are exposed. The optimal step between the racks is 2.5 -3 m. The height of the racks should be 10-15 cm higher than the expected ceiling level. The upper sections are attached to the vertical racks, which are connected at the top. All connections are fixed with plywood pads fixed on the beam with self-tapping screws.

On the racks of the boards, runs are attached, on them - crossbars. The crossbars are fixed with a temporary support and then fastened with boards. In the upper part, a beam-girder is mounted, braces are installed and fixed.

Insulation and waterproofing of a sloping roof

Under the rafters, from the inside of the room, with the help of brackets, a vapor barrier is fixed, monitoring its uniform tension (more). A counter-lattice is stuffed onto the rafters. Sheets of mineral wool or expanded polystyrene are laid between the rafters, followed by waterproofing. It is fixed with counter rails going from the eaves to the ridge and overlapped. Thanks to these counter-rails, ventilation of the entire “pie” is ensured and the integrity of the film is maintained. Waterproofing, laid with several layers of overlap, minimizes the risk of roof leakage. Some (up to 2 cm) sagging of the film is acceptable.

Roofing

After waterproofing, a crate is mounted on the rafters. The step between the rails depends on the selected roofing material, so that it is convenient to mount it. Usually it is 20-25 cm for a soft roof and 30-35 for a hard one. In order to avoid problems with laying roofing material in the future, pay attention to the straightness of the arrangement of the lathing laths.

Laying roofing material broken roof occurs according to the same technology as on the gable.

A sloping roof is a rather complex structure compared to a conventional gable roof. When designing and erecting it, it is better to turn to professionals if there is little experience in construction.
Tiling is not the best the best choice for a sloping roof due to its large weight. It is better to replace it with an alternative - bitumen tiles or metal tiles.
It is necessary to provide ventilation in the roof and install vents in the ridge part.
If you plan to use the attic as a living space, you need to be especially careful about its insulation and not save on vapor barrier.

To date, one can safely classify a sloping roof as a popular and effective roofing structure. To build and equip such a structure, you will need certain building skills, the ability to accurately perform basic calculations.

If you understand this issue, then the creation of an original and spectacular roof will be possible, while it will be possible to save the budget on hiring specialists. And having studied the variety of photos of broken roofs on the network, you can choose the option for your own home.

Sloped roof features

The design in question is considered an excellent option when building a house with an attic. For practical reasons, when the area of the site is small, but there is a desire to have a house with additional usable area, many developers prefer house projects with a sloping roof. And high ceilings in the finished house can give a feeling of free space.

Compared with the usual gable and even more so pitched roof building a polyline will be a more complicated process. In addition, this option is more suitable for square-shaped houses. Narrow and long buildings with an attic are practically not popular among private developers, but there are exceptions.

The amount of consumable material is determined, focusing on the geometric features of the roofing system. Worth paying Special attention drawings of a sloping roof, the detailed preparation of which is an integral point on the way to its creation.

It is also important to find out the bearing capacity of the rafters. The reliability and durability of the sloping roof depends on how accurately the calculations are made.

You need to take into account the following:

weight of the roofing material;
load from all insulating components of the roofing pie;
step of rafters and battens;
weight of the crate and counter-crate;
the length of the slopes from the eaves to the ridge;
slope angle;
seasonal and possible future loads.

There are a sufficient number of formulas and specialized programs that allow you to produce accurate calculations with data on all of the above. As a result, it will become clear whether the characteristics of the truss system will need to be adjusted.

materials

As soon as the calculation of the sloping roof is made, you can proceed to the next step - the acquisition of all necessary materials. Firstly, a timber of the appropriate size is bought to create a Mauerlat, install rafter legs, struts, etc. For battens and counter battens, a cut board is purchased.

The ideal option is coniferous wood, the moisture content of which does not exceed 20%. It is necessary to exclude bars and boards containing large knots. Traces from the actions of woodworms, as well as blue spots, indicate that this wood is unsuitable for arranging a truss system.

After delivery to the site, the material is treated with an antiseptic. Additionally, agents that prevent decay and fire retardants are used. The latter are necessary for protection against fire. They should be applied in two layers, it is faster and more convenient to use a sprayer, but you can use a brush.

Before proceeding with the direct construction of the roof structure, the impregnated wood must be completely dry.

Self-tapping screws of different lengths, mounting plates and corners, bolts with nuts and washers are also bought from materials. You will need hydro and vapor barrier films, insulation (usually mineral wool) and itself roofing.

Sequence of work

To answer the question of how to make a sloping roof with your own hands, you need to have an idea of the sequence of steps for its construction. Let's briefly outline them. First you need to fix the mauerlat - a beam that will distribute the load from the rafter legs along the wall.

Next, the rafters themselves are installed in accordance with the design drawings. A sloping roof implies two types of rafters - layered and hanging. Thanks to the first, the basis of a sheer roof slope is created, and the upper rafter legs are attached to them, thereby transferring the load to the Mauerlat. The upper rafters are connected to the attic ceiling beams, which, in fact, are puffs.

If the project involves the installation of struts and struts, they are mounted in the next step. On the extreme rafters, which are located at the ends of the building, must be installed additional frames. They will serve as the basis for the gables, arrangement of door and window openings.

An edged board is nailed to the rafter legs, which will serve as a support for the insulation sheets and for finishing attic room.

Top fixed vapor barrier membrane. Further, mineral wool is laid between the rafters, and this must be done by surprise. Then comes the waterproofing layer of the roofing cake.

A counter-lattice is stuffed over the waterproofing, creating ventilation gap, then the crate itself. The finishing material, for example, a metal tile, is attached to the crate using self-tapping screws. Work is carried out from the bottom of the roof, and when they reach the hanging rafters, they make a small visor over a steep slope.

At the final stage, drainage elements are installed. The finished roof, subject to the technology, will not yield to analogues made with the involvement of specialists.

Photo of broken roof

Roof erection attic type is an effective solution for a rational and elegant extension of living space. The construction of a sloping roof is an economically profitable and reasonable enterprise today, allowing the developer to get precious living meters almost "for nothing".

Advantages and disadvantages of a sloping roof

Before you build a sloping roof with your own hands, let's find out its main advantages and disadvantages.

Main advantages:

the roof can be built on the infrastructure of an old residential building;
increasing the area of residence through the use of attic space;
the building receives a complete and unique appearance;
the attic can be built in one or two levels;
reduction of heat losses through the roof of the structure, as a result - in winter time reduction in energy consumption.

Flaws:

reduced wall height, which is caused by sloping ceilings;
demanding and complex technologies for hydro and thermal insulation;
the use of roof windows in the premises, which are significantly more expensive than conventional counterparts;
snow accumulation in winter period on the skylights leads to a decrease in insolation in the room.

It follows that if a broken roof is made correctly, then many shortcomings can be avoided and its profitability becomes obvious.

Requirements for the construction of sloping roofs

The construction of a sloping roof is a technically complex process that must be carried out by professionals or people with sufficient skill and experience in this type of work. Do-it-yourself construction of a sloping roof is within the power of a person who already has some experience in roofing, but an experienced specialist should make an accurate calculation of a sloping roof. It will be impossible for a beginner to take into account all the subtleties and nuances.

Before you build a sloping roof, you need to know what requirements are placed on it.:

height attic rooms must be at least 2.2 m;
ventilation must be efficient eaves overhang to the skate; poor ventilation can lead to the accumulation of condensate in the under-roof space and possible leakage;
roofing should have a low specific gravity and sufficient practicality;
it is necessary to constructively provide for an increase in additional loads on the walls of the structure;
special attention must be paid; there is no thermal cushion above it, therefore, the greatest heat loss occurs in it than in the lower floors of the room;
fire safety must be ensured by the processing wooden structures flame retardants and antiseptics.

Sloped roof rafter systems

The main difference between broken roofs is that only two types of rafters can be used in them. Either only layered rafters, which are installed on all slopes, or layered rafters are used on the lower slopes, and hanging on the upper ones.

Before you make a sloping roof, you need to determine the angles of inclination of the lower and upper slopes of the roof. The optimal angle of a sloping roof for the lower slopes is 60-70 °, and for the upper 15-30 °.

There are three main schemes:

Sloped roof installation

The sloping roof truss system is a modular design in which the rafters act as the lower roof slopes, and the upper roof slopes can be made of hanging or layered rafters.

Before you make a sloping roof with your own hands, you need wooden elements truss truss treated with special solutions of flame retardants and antiseptics!

For the elements of the truss system, wood is selected from coniferous trees with a moisture content of 18-22%.

How to build a sloping roof, step by step instructions:

Insulation, hydro and vapor barrier of a sloping roof

After the frame is assembled, they begin to arrange the roofing pie. First, a vapor barrier material is attached. It is necessary to prevent the penetration of steam into the thermal insulation layer. Then there is the laying of thermal insulation. Basalt insulation is most often used as a material. Special requirements are imposed on the laying of thermal insulation. It may consist of several layers that are overlapped to prevent possible "bridges" of cold.

Treat the insulation gasket responsibly! Poorly executed thermal insulation can lead to thermal "breakdowns", which will negatively affect comfortable living in the attic room.

The density of the insulation must be at least 35 kg / m 3. Such a density is necessary for rigid bonds and conservation geometric shape heat-insulating material so that it does not shrink and compact on steep slopes.

Do not use roll insulation with a density of less than 35 kg / m 3. Over time, such a heater deforms, creating empty cavities inside the roof, which will lead to its freezing!

A waterproof breathable membrane is laid on top of the insulation. It allows the passage of vapors from the insulation, while holding the water column.

Not less than important point is the ventilation of the under-roof space from the roof overhang to the ridge. The resulting condensate, from differences in external and internal temperatures, must be removed by natural ventilation and drying. In complex roofs with many kinks and valleys, it is easy to make a mistake and make insufficient air. As a result, local accumulation of condensate in poorly ventilated places and the appearance of a leak are possible.

Considering various options roofs for their home, many owners stop on a sloping roof. This article offers information about the features, pros and cons of the design, as well as about the various types of sloping roofs. After reviewing the proposed material, you will get an idea about the calculation of the roofing system, installation technology and the reasons for the economy of such systems.

House with an attic under a sloping roof

Sloping roof: device features

trend modern construction is the desire to increase the functionality of the house without losing external attractiveness. The broken structure fully meets these needs: it not only transforms the appearance of the building, but also allows rational use of the under-roof space. For this reason, despite the complexity of the structure, broken roofs are increasingly decorating country cottages.

The sloping roof is a derivative of the usual gable roof. Unlike the latter, each slope of a broken structure has a bend line, on which the angle of inclination changes. Thanks to this detail, the number of slopes doubles, and the pediment (the lateral vertical surface between the slopes, usually triangular in shape) becomes pentagonal. Such a change is reflected in the rafter system of a sloping roof. It becomes more complex, lower and upper rafters appear, and the roof is characterized by the following parameters:

lower rafters. Set a steeper angle, not less than 60°.

Schematic diagram of a sloping roof

Top rafters. An angle of about 30° is chosen for them.

The location of the slopes. The walls of the building or floor beams extended beyond the walls can serve as a support for the slopes.

All these changes are needed in order to maximize the attic area. The resulting space is usually used for attic equipment, which is why this design is called mansard roof. A house with a sloping roof and a veranda, common in private housing construction, is considered the most convenient for living; the roof in such buildings is supplied with the following additional elements:

Window. Energy-saving windows with safety double-glazed windows (with internal laminated triplex glass) are relevant.

Windows of various types in sloping roofs

Balcony or terrace. A good way to increase the level of comfort and usable attic area. The decision to acquire this spectacular detail will require a more complex design and additional strength calculations.

House with a terrace on the attic floor

Bay window. The original architectural solution that decorates the building and also expands living space. Usually, they strive to glaze the bay window to the maximum in order to increase the natural lighting of the attic.

house with bay window

Cuckoo. This detail got its name because of the similarity with the famous wall clock. The cuckoo has a separate truss system associated with the main one. In form, a single and gable structure is distinguished, as well as hip and arched; the latter can be found on houses in the style of an Alpine chalet.

gable cuckoo

Sloping roof: advantages and disadvantages

Before making a choice in favor of this roof, you should get acquainted with its pros and cons. The advantages include the following qualities:

You are getting additional living space, which is especially valuable for small areas where you have to save every meter of the territory.

You are getting comfortable space, in which (unlike a gable roof) dimensional furniture is easily placed. If desired, additional hidden cabinets can be placed in dead zones (between slopes and walls).

Attic cheaper than the construction of a full-fledged second floor or the expansion of the perimeter of housing.

Well-designed attic reduces heat loss which means energy savings.

appearance private sloping roof houses wins compared to a classic gable roof.

Sloping roof in classic style

TO negative aspects sloping roofs include the following facts:

Finance. Broken roof will cost a large amount than gable, as more wood and materials for the roofing cake will be required.

Use restrictions. Such a roof is the best solution for regions with snowy winters. Snow on the windows, located at an angle, does not allow sunlight to penetrate into the attic. If the roof is not designed correctly, snow gets under the ridge or at the break line of the slopes, and accumulates inside.

The Importance of Ventilation. The lack of ventilation leads to the accumulation of condensate in the thermal insulation layer and accelerated wear of the truss system.

6 types of broken mansard roofs

In suburban housing construction, for arranging an attic, several options for broken systems are used, which include:

Shed. It has the form of an inclined plane resting on walls of different heights. To implement such a roof, you will need the simplest truss system, although you will not often see it on residential buildings. Outwardly, such a house looks non-standard; a panoramic window is often equipped in the larger (high) wall of the attic floor.

House with a garage and an attic under a pitched roof

gable. A classic of private construction, characteristic of rectangular buildings. It has many solutions with vertical gables and different locations of the ridge. The ridge can be placed above the middle of the building (symmetrical design) or offset from the center (then the roof has an asymmetric appearance). Due to the slope of the slopes, the space under the roof is used irrationally: it is impossible to arrange high ceilings, and a significant part of the area is lost in dead zones. You can raise the ceiling only by increasing the angle of the slopes and the height of the ridge; but such a solution is unsafe in regions with strong winds.

Attic with gabled roof

Variety gable mansard roof - one and a half floor. The walls are raised to a predetermined level, a roof structure with two slopes. The building was called "one and a half floors."

broken line. Each slope consists of two parts with a change in slope. Projects of houses with a sloping roof allow you to significantly expand the usable area (the attic space is approximately 15% less than the area of the first floor).

Project of a house with a sloping mansard roof

Trekhskatnaya. Asymmetric design, which can be found on attached buildings. The place of the pediment is occupied by the third broken slope.

Four-slope(hip). The place of the pediments is occupied by broken slopes. Technically, this is the most complex structure which needs precise calculation. The advantage is resistance to wind and snow loads, external attractiveness and minimal load on the foundation. Disadvantages: reduced usable area (it is often possible to straighten up to your full height only in the center of the attic), increased costs for organizing a roofing pie.

Attic floor with a balcony under a hip roof

On our website you can find contacts of construction companies that offer roof repair services. You can directly communicate with representatives by visiting the exhibition of houses "Low-Rise Country".

Attic under a sloping roof: profitable or not

At first glance, the installation of an attic floor under a sloping roof is a profitable enterprise, since you can save on the construction of walls and at the same time get additional space. This statement is half true; Savings will be spent on other components, which include:

truss system. To build a sloping roof from boards and other lumber, it is necessary to estimate the cost of the structure. The final estimate will be influenced by the type of structure you choose and local lumber prices. The best choice would be sawn softwood with a moisture content of 18-22%.

Components of a roofing pie. If you are planning a residential attic, you will not be able to save on insulation, hydro and vapor barrier. To maintain the proper temperature in the room, a decent insulating layer will be required (SNiP standards for the European part of Russia provide for a layer of mineral wool from 20 cm).

Video description

About a house with an attic and a balcony in the following video:

Window. Two types of window packages are used - vertical and in the plane of the roof. Tilt windows cost more than windows in a house one and a half to two times; they are equipped with a reinforced swivel-type frame and glass that can withstand snow cover. Their installation will also be more expensive, since it is necessary to ensure the tightness of the openings and think about snow retainers above each window. For dormer windows a separate rafter system is required, which complicates the roof topography and makes installation more expensive.

The choice of roofing. Popular metal-based materials (metal tiles or profiled sheets) are not the best choice for arranging such a structure. Metal-clad roofing is characterized by high thermal conductivity and a strong drumming effect in rainy weather. These features will force you to use additional heat and sound insulation, which, quite expectedly, will lead to additional expenses.

Skylights are intended for ventilation or exit to the outside.

It may seem that the construction of a broken mansard roof is not so cheap option as seen at first. However, the real savings still exist and look like this:

Foundation savings. Because attic floor lighter than a full-fledged one, the foundation is laid less powerful than for two-story house. Since the foundation costs can be up to 25-30% of the construction cost, the gain will be tangible.

Savings on roofing material. By buying more expensive roofing, you can save on the filling of the roofing cake; however, for this it is necessary to calculate more than one option.

Delayed construction. Often, lumber is purchased for the truss system high humidity. If the roof is assembled immediately, moisture will begin to be absorbed into the heat-insulating layer, which is not dangerous for a well-assembled pie, but will bring problems to a roof made with violations. Delayed commissioning will allow the wood to dry properly, which will reduce future problems.

Video description

About roof windows in the following video:

The nuances of calculating the attic roof

Roof calculation solves several problems:

Calculation of the truss system during construction. It is especially important in the presence of additional details - windows, balconies, access to the roof, terraces. Such details increase the load on the rafters, and the design needs to be adjusted.

Calculation of the truss system during reconstruction. Alteration non-residential attic in the attic is limited by the size of the existing building. For all load-bearing elements, a competent calculation of their cross section will be required.

Calculation of building materials. So that the construction of the roof is not slowed down due to a sudden shortage of timber, metal tiles or self-tapping screws, they pre-calculate right amount materials.

Scheme-calculation of a broken roof

The calculation procedure for a broken roof is as follows:

Calculated future roof area. The linear dimensions of each slope are measured; the area is determined (by multiplying the length and width). The final number is the sum of the areas of all slopes.

Calculated required amount of roofing material.

Calculated load bearing capacity. For this, the average snow and wind load that the structure can receive during the season is determined.

An online calculator for calculating the sloping roof truss system is offered on the Internet. As a rule, it allows you to calculate the angles of inclination of the slopes, the parameters of the lathing, the permissible load and the required amount of roofing material. The result is based on the following parameters:

Laying width(projection of the slope onto the base) of each element.

lifting height(distance from the top of the slope to the base of the roof) of each slope.

Length of base and overhangs.

roofing material(weight included).

Video description

About calculation hip roof with a bay window in the following video:

The online calculator allows you to get approximate values and becomes practically useless if the roof has a more complex geometry and additional details (hatches, windows). It is almost impossible to make a correct calculation of the structure on your own and not avoid mistakes, despite numerous assurances to the contrary scattered across construction sites.

Create an accurate drawing with detailed description only a person with an engineering education and work skills is capable of all knots and connections, but not everyone has a friend who can be entrusted with such a responsible task. Most practical solution an appeal to a specialized construction organization is presented, which offers many additional advantages:

Company specialists calculate the roof of any complexity and carry out turnkey installation.

The customer is provided detailed Technical information about the advantages and disadvantages various types roof coverings.

When calculating will be taken into account not only basic (as in online calculator), but also Extra options: the weight of waterproofing and insulation, the presence of windows, the weight of equipment that is supposed to be installed on the roof.

Turnkey sloping roof installation - quality assurance

You inform about the prices of materials and estimated cost. The situation when there is not enough material or, conversely, a significant surplus remains, is excluded.

After agreeing on the details a contract is signed and an estimate is made, the terms of delivery and payment are optimized.

Company provides a guarantee for the work done.

Conclusion

Sloped roofs have impressive dimensions and a complex internal structure, but they compare favorably with other roofs in that the installation takes place according to a modular scheme. Most of the components of the truss system are assembled on the ground and rise up in the order in which they will be located. Heavy construction equipment is not needed for such work. The advantages of a broken mansard roof lie on the surface - your house receives not only a roof, but also additional living space. Properly equipped, it will be suitable for year-round operation.

Using the attic instead of a full-fledged second floor allows you to rationally use the available space and significantly expand the living space. There are many options for attics; the most popular of them is a sloping roof, which is not only aesthetically attractive, but also financially profitable. If you wish, you can build such an attic with your own hands.

Users often search:

What parts does a broken attic consist of?

The first stage of roof construction is design and calculation; regardless of whether the project is ordered in a special organization or it is planned to make a design drawing on your own, first of all you need to figure out what main parts the broken attic consists of.

In essence, a sloping roof is a residential attic, well enough insulated and protected from moisture and noise to make it comfortable to live in. Therefore, in terms of design, it differs slightly from an ordinary gable roof.

The following main elements of a sloping roof are distinguished:

vertical racks;
puffs - horizontal beams;
rafters - stiffeners, which are the skeleton of the entire structure;
struts - diagonal beams supporting the rafters;
Mauerlat - wooden beams with special fasteners connecting the structure with the walls of the house;
ridge run- aggregate upper elements truss system;
grandmas - fasteners that ensure the rigidity of the hanging rafters;
contractions - horizontal struts that remove part of the load from the rafters;
crate - a frame for fastening roofing material and insulation;
roofing - can be made of ceramic tiles, different types slate, profiled sheet and many other materials;
heat, hydro and sound insulation.

Thus, the whole structure consists of a set right triangles. They are connected to each other with wooden beams. All the elements described are easy to find on the drawing of a broken attic.

Technical requirements for sloping roof

Sloped roofs are subject to the following requirements:

the height of the attic walls must exceed 2.2 m;
should be provided good ventilation so that moisture does not condense under the roof;
roofing material must have a small mass;
the design must provide for measures against the impact of additional load on the truss system - that is, the roof elements must withstand not only their own weight, but also, for example, snow;
the attic loses heat faster than the lower floors, so special attention should be paid to thermal insulation;
to provide fire safety all wooden beams and batten elements should be treated with flame retardants.

Varieties of truss systems

The device of a sloping roof is very simple - its slope, as it were, breaks into lower and upper parts, each of which is set at its own angle. Most often they are mounted at an angle of 60–70 °, and 15–30 °, respectively.

Based design features attic can be distinguished such types of mansard sloping roofs.

Two types of rafters are used: hanging and layered. The attic floor beams are installed, a little short of the edges of the walls of the lower floor. The lower slope is made of layered rafters, which are attached to the walls of the house with the help of a Mauerlat. The frame of the attic walls is made from the racks. Such triangles are installed along the walls and connected by contractions. From above, they are joined by triangles of hanging rafters, based on a puff.
To increase the area of \u200b\u200bthe room, the lower edges of the rafters can be brought outside the house. In this case, they will not be attached to the Mauerlat, but to the ceiling, which, in turn, is held on external walls oh at home with the help of Mauerlat. The rafters are necessarily supported by struts. Racks go deep into the floor beams by no more than a third of their thickness.
This sloping roof truss system is different in that the upper triangles are made from layered, not hanging rafters. In this case, the puffs are supports for the uprights of the upper triangles.

Sloped roof calculation

Before starting work, two calculations must be carried out:

determination of the amount of necessary building materials;
calculation of the bearing capacity of the structure.

Determining how much material is needed is very simple due to the simple geometry of the sloping roof. Bearing capacity is not so easy to deal with. For its calculation it is necessary to take into account:

weight of the roof;
approximate mass of snow;
the mass of the crate;
a lot of steam, hydro and thermal insulation materials;
roof dimensions;
installation angles of slopes;
the installation step of the elements of the truss system and roofing sheathing;
additional load: mass of people and equipment, windows, ventilation, etc.

Based on these data and with the help of special programs, the bearing capacity is calculated. Depending on what bearing capacity is required, the cross-sectional area used in construction is selected. wooden beam. If something does not suit you, the project can be corrected by changing the truss system, choosing a different roofing material, placing the rafters less often.

In most programs, the design of a sloping roof can be visualized - on the 3D model, you will immediately see how the changes will affect the appearance of the attic.

What materials need to be prepared?

After the development of the project, it will be clear what beam with which section should be used, which roofing material is better to choose, what should be the roof lathing. You will have to purchase a wide variety of lumber: timber for the formation of Mauerlat, edged boards for the rafter system, boards for battens. They need to be properly selected so that the design is durable and reliable.

Tips for choosing lumber:

coniferous woods - pine, spruce - are best suited for building an attic - they are strong and rigid enough to withstand the entire load;
wood should be well dried - its moisture content should not exceed 20%;
the material must be free of knots, cracks, traces of biological damage and other defects.

Before installation, all wood is treated with flame retardants and antiseptics, as well as impregnations from decay. Such processing should be repeated periodically so that the load-bearing structural elements do not have to be replaced.

In addition to the main material, you need to stock up on metal fasteners for connecting the rafters to the Mauerlat and to each other, insulating and roofing materials.

Roof installation

Mauerlat installation

The construction of a sloping roof begins with the installation of a Mauerlat, to which the ends of the rafters will be attached. The nuances of this stage vary depending on the material from which the lower floor is built - if its walls are stone, you need to punch holes for anchors in them in advance and install fasteners. The spacing between anchors should not exceed 2 m.

Placed on the surface of the wall waterproofing material. Then the beam is marked, holes are drilled at the points of installation of the fasteners. Mauerlat is put on the anchor and tightly attracted with nuts.

Installation of floor beams

Installation sequence:

first, extreme beams are placed from the ends of the building;
strings are stretched between them to indicate the plane;
intermediate beams are installed.

Mounting racks

Racks must be set strictly vertically. The principle of operation is the same as in the case of floor beams - first, the extreme racks are mounted, then the intermediate ones in the same plane. The step between the structural elements should not exceed 2 m. The racks are fixed with temporary struts. The height of the beams is 10 cm more than the planned height of the ceilings.

Runs from edged board. The result should be a finished frame for internal walls attic.

Installing puffs

The transverse beams are connected not to the racks, but to the girders, using metal roofing corners. If the width of the room is large, it is worth installing temporary spacers under each puff so that when walking on them during the construction of the upper slopes, the beams do not break or sag.

Rafter installation

First, the lower rafters are mounted. They are placed in the following order:

mounting points are planned on the Mauerlat - the step between them should be 1–1.2 m;
on the rafter legs the attachment points are cut according to the template;
first, the extreme rafters are attached, then, as before, intermediate ones along the twine;
struts are installed in accordance with the drawing.

The upper rafters are placed in the same way - according to the template. They are attached to puffs and interconnected; a longitudinal connection with a ridge beam is required only if the length of the attic exceeds 10 m. Otherwise, struts can be dispensed with, with which the construction of a broken mansard roof will be quite rigid.

The last stages of work are the sheathing of the gables and the fastening of the lathing for the roof. Window openings should be left in the gables (at least 1/8 of the total area of the outer walls of the attic).

Structural insulation

On the finished frame, it remains only to lay roofing cake. Its first layer is a vapor barrier, which prevents moisture from penetrating into the insulation. A heat-insulating material is laid on the vapor barrier membrane - it is recommended to use stone basalt slabs. They are laid in several layers with a shift in the joints, which will protect against the occurrence of cold bridges. The size of the slabs should be several cm larger than the spacing between the beams of the counter-lattice. So that the insulation does not sag and lose its performance characteristics, its density should be at least 35 kg / m 3.

From above, the insulation is covered with a waterproof membrane, which allows steam to pass through, but does not allow liquid moisture to penetrate into the room. A roof is laid on top of the waterproofing layer - the features of its installation depend on the chosen material.

After the installation of the roof, only the finishing touches will remain - the installation of drainage systems, decorative trim. Inside finishing material also attached to the crate over the thermal insulation. Sloping roof built. As you can see, it is quite possible to do it yourself - only the design and calculation will probably have to be entrusted to professionals.