Mansard roof rafter system - drawings. How to make a broken mansard roof with your own hands Step-by-step diagram of a mansard roof assembly

A house with an attic is not just additional living space, but also a presentable appearance of the entire structure. Even if the room under the roof is not heated and is used only in the summer, it still has a powerful " air cushion", promoting heat retention inside the entire building.

Making an attic on your own will be difficult, especially if you do not have the relevant experience, because it is a fairly massive and complex structure.

The attic space can be installed under various types roofs, but the most popular is a broken or gable design. According to their structure, they are slightly different from each other.

In order to decide which design will be more suitable for your home and will be easier to install, you need to consider both options in more detail. In addition, the master who will be involved in the construction of the attic roof must understand which of the two types of structures rafter system choose.

Any roof belongs to one of the existing two types of rafter systems, it is layered and hanging design. Each of them has a different feature, and which one to choose depends on how the load-bearing walls of the structure are located.

Hanging structure

A hanging structure is a rafter system that rests only on the outer main walls. This happens when in the house itself, except external walls, there are no capital partitions.

This design can only be used if the distance between two main walls is no more than 8 m, since this system puts a high load on the foundation. To reduce it, in a hanging system they use different elements, such as ties and headstocks, struts and crossbars. For example, the headstock hangs the tie to the ridge connection, and the struts pull the beams to the rafters.

For floor beams in a hanging system, hewn logs or fairly thick bars installed on an edge are used. Their cross-section must be at least 100x200 mm. The floor in the attic should be as reliable as possible, and in order not to make mistakes in the parameters, it is better to entrust the calculations to a specialist.

Layered system

The layered system, unlike the hanging one, is not simply supported by two outer load-bearing walls ah, but also on capital partitions installed on the foundation. Therefore, when planning the construction of an attic, you need to think in advance what the structure will be like. strip foundation, on which permanent partitions will be installed. The layered system is perfect for installing an attic because it can withstand high loads compared to the hanging version. It provides a good base for the floor beams and therefore for the attic floor.

If you make a broken version of the attic roof, then it makes sense to use a combined roofing system, that is, the side rafters are installed in a layered manner, and the ridge rafters are installed in the form of a hanging system.

Do-it-yourself mansard roof: video, photo

When building a house from blocks or bricks with an attic, its front side is often built from the same material. This is convenient because you don’t have to calculate the parameters of these roof elements and assemble them from bars to lift onto the wall. But it is important to understand that the walls of the building must necessarily stand on a reliable foundation and have good thickness, since such a pediment puts a significant load on the main building.

If the attic serves as another floor year-round, then a gable wall made of foam blocks or bricks is an excellent option for creating a living space under the roof.

In order for attic rooms with a gable roof to be spacious and have a normal height, the angle of the roof slopes should be approximately 45-50°, depending on the width of the end part of the structure. If you take a smaller angle, the volume of the room will significantly decrease. Increasing the steepness of the slopes will make the roof unreasonably high, it will become heavier, will have greater windage under wind loads, and the cost of materials will be inappropriate.

Of course, the installation of a gable roof is simpler compared to a broken structure, since straight rafters are used without additional connections or any kinks. But the broken design allows you to make the room in this part more spacious, and the ceilings correspondingly higher.

The broken system is much more complex in design, calculations, and roofing, but it not only creates a more spacious space under the roof, but also gives solidity to the entire structure. Its main difficulty lies in large quantities complex connecting elements. All connections must be made in accordance with the technology, otherwise the roof will turn out to be unstable.

If the walls are built of brick or stone, then it is better to lay out the front parts in advance during the general laying. In this case, in order to create a unique rafter system, aligned with the finished gables, you can install intermediate rafters and special supporting fastenings to them.

Before purchasing and preparing material for a particular system, you need to draw up a design project with the appropriate dimensions - it will become the main guide for preparing and assembling elements during installation.

Video: rafter system for a sloping attic roof

Attic project

When developing a scheme for building an attic, it is better to do this in different projections in order to clearly understand how the elements of the rafter system will be placed. It is important to correctly calculate what the height of the roof ridge should be, since the size of the area depends on it.

When preparing a design diagram for constructing a roof for an attic, it is necessary to calculate the height of the ceiling, ridge and total area of the room.

The minimum height from the floor to the ridge is 2.5-2.7 m, but if this distance is smaller, then the room cannot be called an attic; the name attic is more suitable for it. This indicator is established by SNIP standards.

To ensure that all elements are accurately drawn and have the correct location in common system, it is necessary to start from a figure with right angles, namely from a square or rectangle - a cross-section of the attic space being created. Based on the width and height of the future room, you will never be mistaken with the angles at which the roof slopes are located, with the location of the rafters, ridge and other supporting elements. Having found out these parameters, they must be immediately entered into the drawing.

First of all, you need to calculate the middle of the width of the front wall. Further from this point, the height of the ridge, the attic ceiling, the location of the walls (racks) and the size of the eaves overhang are determined.

Due to the fact that each of these structures has a certain number of connecting nodes with different configurations, it would be nice to draw each of these connections separately in order to understand in detail the features of the pairing of all the elements that are connected at this point.

All rafter systems include basic and additional elements, which may not be found in every design. The main components of the attic roof include:

floor beams (the basis for the remaining elements of the system). They are laid on main walls.

A rafter leg consisting of two sections (in the case of a broken pattern) or straight in a gable system. The top rafter in this case is called the ridge rafter, since it forms the highest point of the roof - the ridge, and the rafters that form the walls of the attic are called side rafters.

Mauerlat is a powerful beam that is attached to the main side walls. This element must be installed rafter legs.

A ridge board or beam is an integral element for gable roof, but is not always used when installing a broken roof.

Constructions are supporting elements that are required to strengthen a broken and gable structure. In the first case, the side and ridge rafters are attached to it, and in the latter, the stand acts as a good support for a long rafter. Moreover, the racks are the frame for covering and insulating the attic walls.

Diagonal connecting elements additionally fasten the longitudinal beams or posts and rafters, thereby making the structure even more durable.

Inter-rafter purlins are installed in the case of a broken roof for structural rigidity.

Attic floor beams are used in both versions of the system - they connect the racks with them, and they act as a frame for the ceiling.

In order to be sure that the project is developed without errors, it would be a good idea to show it to a specialist. It will determine how correctly you selected the attic parameters to the length and width of the walls of the building.

Video: calculating a mansard roof using software

Material parameters for the construction of an attic roof

When the graphic element is ready, then, based on the dimensions set on it, you will be able to calculate the amount of materials that will be needed for the construction of the attic roof. It is necessary to select materials according to their characteristics, which must meet environmental and fire safety requirements.

For wood, it is necessary to provide an antiseptic treatment, which will significantly reduce the flammability of the materials. For construction you will need:

boards for rafter legs, the cross-section of which is selected based on the results of calculations, which you will learn about a little below.

Beam of 150x200 or 100x150 mm - for floor beams, depending on the width between load-bearing walls, rafter system, as well as for purlins, valleys or diagonal legs - if, of course, they are provided for by the design.

Beam from 100x150 or 150x150 mm, intended for laying the Mauerlat.

Typically, timber 150x150 or 100x100 mm is used for racks.

Unedged board for the subfloor, as well as some fasteners.

Annealed steel wire with a diameter of 3-4 mm - for fastening some parts.

Bolts, nails, staples of various sizes, angles of various configurations and other fasteners.

Lumber for counter battens and sheathing for roofing material- depending on the type of roof.

Vapor barrier and waterproofing membranes.

Insulation materials intended for roof thermal insulation.

Roofing material and special fasteners.

Rafter section

The rafters provide a roofing element that accepts the main external loads, which means special requirements are imposed on their cross-section.

The size of the required lumber depends on many parameters - from the step between the rafter legs, the length of these legs between the support points and ending with the wind and snow load that falls on them.

The geometric parameters of the rafter system are easily determined in the drawing. But to understand other parameters, you will have to turn to reference materials and do some calculations.

It's no secret that the snow load differs in different regions our country. Below in the figure you will see a map on which all of Russia is divided into zones demonstrating the snow load.

In total, 8 zones are distinguished (the last one is considered extreme and can not be considered for the construction of an attic roof).

Sg is an indicator in the table (carefully study the map and the table attached to it).

μ is a correction factor that depends on the steepness of the roof slope.

For example, if the roof slope angle is less than 25°, then - μ=1.0; if from 25 to 60°, then μ=0.7; if it is more than 60°, then the snow will not linger on the roof, and the snow load is not taken into account.

If the attic roof is of a broken structure, then for its different sections the load may have different values.

The angle of inclination of the roof can be determined by a simple ratio of the height and base of the triangle (usually half the width of the span) or using a protractor according to the drawing.

This indicator also largely depends on the region where the structure was built, on the height of its roof and on the characteristics of the environment.

And again, for the calculation you will need to determine the initial data from the map and the table attached to it.

The calculation for this task will be carried out using the following formula:

Wp = W × k × c

W – value in the table, depending on the specific region.

k – coefficient taking into account the location and height of the building (see table).

The letters in the table indicate the following zones:

A - open areas, forest-steppes, steppes, tundra, deserts, forest-tundra, sea coasts, reservoirs and large lakes.
B – urban areas, areas with frequent wind obstacles, artificial or relief, at least 10 m high, wooded areas.
B – dense urban development, building heights from 25 m.

With– a coefficient that depends on the prevailing wind direction (wind rose of the region), as well as on the angle of inclination of the roof.

With this coefficient, the matter is much more complicated, since the wind can have a dual effect on roofs. So, it has an overturning, direct effect on the roof slopes. However, at small angles, the aerodynamic effect of the wind is of particular importance - it raises the slope plane due to the resulting lift forces.

As you have already noticed, the diagrams that accompany the tables indicate the areas of the roof that are subject to maximum wind loads, and also indicate the corresponding coefficients used for the calculation.

It is worth noting that at slope angles up to 30° (in the area of ridge rafters), the coefficients are indicated both negative (directed upward) and with a plus sign. They somewhat dampen the wind load, and in order to reduce the impact of lifting forces, you need to carefully secure the roofing material and rafter system in this area, using additional connections (for example, annealed steel wire).

As soon as the snow and wind load will be calculated, they can be summed up and taking into account design features system, identify the cross-section of the rafter boards.

Please note that these data are indicated for the most commonly used coniferous materials (spruce, pine, larch or cedar). In the table you can see the maximum length of the rafters between the supports, the section of the board depending on the pitch between the rafters and the grade of the material.

The total load value is indicated in Kilopascals (kPa). Converting this value into the usual kilograms per m2 will not be difficult. 1 kPa ≈ 100 kg/m².

As for the size of the board along its cross-section, it is rounded up to the larger side of standard lumber sizes.

What tools will you need to install an attic roof with your own hands?

Of course, during work you cannot do without a set of tools, the list of which includes:

screwdriver, electric drill;
building level, tape measure, plumb line and square;
chisel, axe, hammer, chisel;
jigsaw, a circular saw, hacksaw;
carpenter's knife

If the work takes place surrounded by competent mentors, step by step and carefully, and the tools are of high quality, the process will be much faster.

Do-it-yourself mansard roof: main steps + video

It is important to strictly follow the sequence of work, because this is the only way the structure will be strong and reliable.

Mauerlat fastening.

The installation of any rafter system should begin with attaching a powerful support beam - Mauerlat - to the end of the side walls of the buildings. It is convenient to install rafter legs on it. It is made from high-quality timber 100x150 mm. The Mauerlat is laid on roofing felt waterproofing laid along the upper end of the wall (regardless of the material).

Thanks to the Mauerlat, the load is evenly distributed across the walls and transferred to the foundation. It is fixed to the wall using metal studs, which are previously embedded in a crown or concrete belt running along the upper edge of the wall of the structure or with 12 mm anchor bolts. They must go into the wall at least 150-170 mm. If the Mauerlat is installed on a wall made of wood, then the beams are attached to it using wooden dowels.

Installation of the rafter system.

Installation of the rafter structure begins with the installation of floor beams, which can be mounted on top of the mauerlat (if you plan to move the beams outside the room, increasing its area). In this design, the rafter legs are fixed directly to the floor beams.

Otherwise, they can be laid on waterproofed walls and secured with brackets or angles to inner edge Mauerlat. This option is used if the rafter legs need to be fixed directly to the mauerlat.

The posts should be at the same distance from the middle of the floor beam. In the future, they will determine the location of the walls of the room, namely its width.

The bars for the racks must have a cross-section corresponding to the size of the floor beams. The racks are attached to the beams using wooden plates and special corners. But first, they are baited with nails, after which they are leveled using a plumb line and building level and only then are they thoroughly secured with the expectation of upcoming loads.

As soon as the first pair of racks is installed, they are fastened on top with a block (tightening). It, in turn, is connected using metal corners to the racks.

When the tie is secured, you will have a U-shaped structure. On the sides, layered rafters are installed on it, which are laid on the mauerlat or attached to the floor beam with the second end.

A groove (special notch) is cut into the installed supports for the timber or in the rafters. With its use, the rafters are installed on the mauerlat beam and secured with metal brackets.

To ensure structural rigidity, struts can be installed from the base of the rack to the middle of the side rafters. If this turns out to be not enough, and you don’t mind the material, then it would be nice to strengthen general design contractions and additional stands.

Then the middle is calculated on the puff. A beam will be attached to this place, which will support the ridge connection of the upper hanging rafter subsystem.

The next stage is the installation of ridge rafters. They can be held together various connections– these can be powerful bolts with metal washers or plates or a metal plate.

After installing them, the headstock is attached to the middle of the tightening and the ridge.

Upon completion of work on one part of the truss structure, it is necessary to do the rest according to the same principle. The distance between adjacent rafters in such a system should be no more than 900-950 mm, but the best option there will be an interval of 600 mm, which will give the structure the necessary stability and rigidity and will be convenient for insulation using standard mats mineral wool. But this significantly makes the structure heavier and increases the cost of materials.

First, the side parts of the system assembly are installed, then the intermediate parts. They are connected to each other by purlins, which are installed between the upper ends of the racks and work like spacers. So, we get a rigid structure of the attic rafters, where there will already be a ready-made frame for finishing the walls.

Waterproofing attic roof

As soon as you have built the rafter system, you can begin finishing it with insulation and other related materials.

It is worth noting that the first coating on top of the rafters should be a waterproofing and windproof film. It is attached to the rafters using a stapler and staples, starting from the cornice. The canvases are laid with an overlap (200 mm), and then the joints are glued together with waterproof tape.

A counter-lattice is placed on top of the waterproofing, which will better fix the film on the surface and create a ventilation distance between the roofing and windproof material. Typically, the counter-lattice is made of boards 50-70 mm thick and 100-150 mm wide.

A sheathing is fixed perpendicular to it, on which the roofing material is laid. As for the pitch between the slats, it is calculated depending on the size and type of sheet roofing material, taking into account the overlap required for it.

If you use soft roof, then plywood sheets are usually fixed to the counter-lattice.

How the roof covering is installed

The roofing material is fixed to the prepared plywood or sheathing. Typically, its installation begins from the roof eaves and then one by one, from one of the edges - depending on the type of roof. Sami roofing sheets are installed overlapped. If metal tiles or metallic profile, then this material is secured using special self-tapping screws with elastic gaskets. Typically, fasteners are matched to the color of the material.

The most difficult stage in coating sloping roof– transition from layered side rafters to ridge rafters. Some difficulties may also arise if the roof has projections for arranging the roof above windows or balconies.

Moreover, if a chimney pipe goes onto the roof, it requires a separate design of the hole in the insulating layer and rafter system, and on the roof - a device around reliable waterproofing. It is worth noting that the work of constructing any roof, including such a complex one as an attic roof, is very important and dangerous, and therefore requires increased safety measures. If you do not have experience in such construction processes, then it is better to entrust their implementation to specialists or invite experienced craftsman, under whose supervision perform all actions carefully and carefully.

Last revision: 12/03/2014

The roof under which the living rooms are located is called an attic. There is no ceiling in this building. This design allows you to increase the total volume of the room and do this with minimal material investment. Roofs may have different shape, but the most popular is the gable sloping roof. In this article we will tell you how to properly make a mansard roof with your own hands.

Carrying out design work

First of all, it is necessary to conduct research on the foundation and walls. The design of a sloping roof is much more complex and heavier than a typical one, so its construction requires a strong foundation. In the process of studying the walls and foundation, it is necessary to determine whether they will withstand this type of roof. If an attic roof is planned during preparation for the construction of a building, then all the features should already be taken into account during the design.

The choice of roof shape must be taken responsibly. Because if there are errors in the calculations or if the parameters are chosen incorrectly, the roof may collapse, and along with it all the supporting structures.

It is best to entrust the preparation of the project to professionals. Modern technologies everything is allowed necessary calculations produce using special computer programs. With their help, optimal angles of inclination and other characteristics are calculated based on the initial parameters. Moreover, all calculations are made in compliance with SNiPs.

The level of ceiling height is the main requirement for comfortable arrangement of the attic. It should be from two and a half meters and above. The broken roof line must be located at a level of about 2.8 meters. In this case, the thickness of the insulating layer, floor projections and interior wall decoration are taken into account.

Before the beginning installation work it is necessary to draw up a clear plan diagram, indicating all the linear parameters of the building, pitched corners and the total height of the house.

Technical terms

A beam that performs a supporting function, transferring the load from the lower ends of the rafters to the upper end of the walls of the structure, is usually called a Mauerlat.
The structure of wooden beams that forms the main shape of the roof is called rafters.
A powerful beam that supports the ties and evenly distributes the load between the individual rafters is called a suspension.
Plywood sheets or flat boards used for laying roofing material are called sheathing.

Roof frame

First, a mauerlat is installed on all four sides of the building, which is a support beam that allows you to transfer the load to the walls of the house from the rafter system. If the main structure is made of wood, then the mauerlat can be either the top beam or the top log. In rooms made of brick or blocks, the support beam is secured using studs or anchors that are already built into the walls during masonry. Such a beam has a cross-section of 10–15 centimeters and is made only from coniferous species wood By inner surface The walls of the house are lined with mauerlat. What remains outside afterwards is improved using decorative masonry.

The support beam is laid on top of the anchor studs and pressed tightly so that indentations from the studs remain on its surface. The necessary holes are drilled along these marks for subsequent fastening. You can also mark the timber using a tape measure, but the first option is preferable and more accurate. Waterproofing is laid on the surface of the wall. You can use roofing felt as it, laying it in two layers. A Mauerlat is placed over the waterproofing layer on the stud and the nuts are tightened.

The support beam is installed on a brick wall using wood plugs. The floor beams are made of coniferous timber with cross-sectional dimensions of 100×200 mm. These beams are laid on the Mauerlat in such a way that they protrude beyond the wall by thirty to fifty centimeters. You can put them in special pockets that were made during the construction of walls. When laid on the Mauerlat, the beams are secured using metal corners and self-tapping screws. In order to lay the ball evenly, first the outer beams are attached, then the intermediate beams are installed along a stretched cord.

Note! Floor beams are installed in increments of fifty to one hundred centimeters. However, experts advise the optimal step is sixty centimeters. This arrangement of the interbeam space allows you to lay the heat insulator without cutting it.

To level them in height, they are propped up or wooden pads are used.

When installing racks using pockets in the masonry, their ends are treated with a special liquid waterproofing material and wrapped in roofing material. They are aligned according to a similar pattern, using a cord.

The racks are mounted on beams that are located along the edges. They are made from timber measuring one hundred by one hundred and fifty millimeters in cross section.

The installation line and height are pre-determined in the corresponding drawing. Be sure to use a device called a level, as well as a plumb line to level the racks. Then they are temporarily fastened in a perpendicular direction using bevels, securing them across and along the axial section of the roof.

All these measures are taken to ensure that the racks are installed without deviations. Any tree can be used for mowing. They are attached to the posts with nails. After the racks are installed along the edges, the cord is pulled between them again. It is used as a guide when installing intermediate racks. Their pitch should be equal to the pitch of the beams. When carrying out a sequence of such work, the result should be two rows of racks that have the same height and are parallel to each other.

Installation

The so-called purlins are laid and fastened onto the already installed racks - boards fifty by one hundred and fifty in diameter. Fastening is done with one hundred and fifty mm nails, as well as with metal corners, which are fastened with self-tapping screws. Crossbars are placed on top of the purlins, which are made from boards measuring fifty mm thick and two hundred mm wide. Their narrow side faces down, which allows for greater rigidity. There will be no load on the crossbar during operation, so these dimensions are considered optimal. But to avoid deflection and increase reliability during installation, temporary supports are additionally placed under the crossbars. These are boards whose thickness should be at least twenty-five millimeters. Temporarily, the crossbars are fastened on top with boards until the process of installing the rafters begins. Additional fasteners are not installed in the middle of the tightening so that they do not become an obstacle during further installation.

After the crossbars, racks and purlins are installed and secured, you should get a fairly rigid structure that will limit the space inside the attic. In the future, it is subject to further strengthening using contractions and struts.

The lower rafters are made of boards with dimensions in diameter: fifty by one hundred and fifty millimeters. To begin with, a template is made from boards of smaller thickness. This makes them faster and easier to process. Applying such a board to the upper purlin, draw the shape of the cut on it with chalk or a pencil, and then this shape is cut out according to the marks. The template is applied to the purlin in the places where the rafters are supposed to be installed. If there is complete agreement in all places, then the upper part of all prepared rafters is cut out according to this template. The lower end of the rafters, which should rest on the mauerlat close to the floor beams, is cut out at the place where it will be attached. The rafters are attached using metal corners, screws and nails.

Note! When it comes to the top rafters, you need to first mark the geometric center of the roof. This is done using a temporary stand, which is nailed to the Mauerlat at one end and a tie located at the end of the roof.

The work is done in such a way that one of the edges of this temporary board corresponds to the center of the future roof. The rafters are aligned along this edge. Again, a template is prepared from a flat board with transverse dimensions of twenty-five by one hundred and fifty millimeters. It is applied to the edge of the previously installed board at the appropriate level and to the purlin on which the lower rafters are supported.

The cuts are marked at both ends of the board, and the template is cut out according to the markings. Checking the correct determination of the center is done by applying the sawn parts of the template to both sides of the roof. If the parallelism condition is met when installing the racks, then there should be no problems with the installation of the upper rafters. After all, they all have exactly the same dimensions.

Using the manufactured template, the required number and corresponding configuration of rafter legs will be made. The rafters are installed on the mounted purlins. In the upper part they are fastened with overhead metal plates using self-tapping screws. In the purlin itself, the rafter parts are inserted into the cuts and secured using special metal corners and self-tapping screws.

Note! In order for the rafters to stand strictly vertically, they are additionally reinforced with struts. With the lower end they are installed on the puffs.

The remaining rafters are installed in a similar manner. By choosing pieces of boards measuring twenty-five by one hundred and fifty millimeters, hanging racks are attached. The upper edges of the hanger are attached to the place where the rafters are connected, and the lower edges to the tie.

Struts are installed on the rafters, which are located in the lower part. They are made from boards with cross-sectional dimensions of fifty by one hundred and fifty millimeters. They rest with an oblique lower cut against the supporting beam and are fastened with metal corners. The upper edges are nailed to the rafter legs from the side. Additionally, through holes are drilled. Bolts are inserted into them and tightened with nuts. Once the bottom braces are installed, all temporary fastenings are removed.

Now it’s time to sew up the gables. They are sheathed in such a way that there is space for door and window openings. When laying floor beams in wall pockets, special boards are reinforced on the lower rafters, which continue the line of the rafters and form the roof overhang. They are called fillies.

If laying is done on a mauerlat, then there is no need to use fillies.

Now you need to make the sheathing. Its type depends on the roofing material. When using roofing felt or roofing felt, the sheathing is mounted solid, without gaps. It is mandatory to place it on the sheathing waterproofing material. After this, you can begin laying the roofing material. If a mansard roof is built with a broken configuration, then it does not need insulation. The walls and ceiling are subject to insulation.

The under-rafter room is quite spacious, which provides good ventilation attic space. At the same time, in the summer, the heating of all rooms in the attic is reduced, and in the winter, additional thermal insulation is provided. For this purpose, windows are left in the gables to improve the ventilation process.

The lathing is designed to perform a number of functions:

redistribution and transfer of the weight of the roofing deck to the rafters;
performing an additional connection of the rafter system;
base for mounting the roofing sheet.

The lathing can be one- or two-layer, continuous or with a vacuum. When installing a roof made of corrugated slate or metal tiles, the sheathing is made of boards that are attached to the rafters with nails. In this case, the distance between adjacent boards can vary in the range of 15-30 centimeters. The final decision is made when using a specific type of coating.

The continuous type of lathing is used when installing soft roofing roll material. In this case, moisture-resistant plywood sheets or oriented strand boards are used. Can be used pine wood material, in the form of an edged board.

Note! When installing such a sheathing, it must be taken into account that the material laid on the sheathing will follow all the contours of its outer surface. Then the frame must be strong and even.

When laying the sheathing material, you need to use a special construction cord, with the help of which the boards or slabs will lie evenly, strictly parallel to each other. Before fastening, the material must be treated with an antiseptic, which will protect it from fungal formations, premature rotting and dampness.

The material for making the sheathing must be of high quality and smooth; preference is given to wood of the first or second grade, without numerous knots or any other defects.

Note! Mandatory requirement– the wood must be pre-dried, otherwise the boards will warp when drying.

To illustrate the process of installing a mansard roof, you can watch videos on the Internet.

Photo

Video

How to insulate an attic roof for a comfortable stay in the room.

The attic is the roof under which the living rooms are located. The shape of the attic roof can be different, but most often the attic is equipped under a gable roof. Most rational decision, which allows you to get the maximum usable area of a residential attic, is a mansard roof with a broken slope line.

The stages of building a mansard roof with your own hands are in many ways similar to the construction of a regular roof, as are the names of the elements that make up its frame. These include:

Mauerlat - a support beam that transfers the load from the rafters to the walls of the building;
Floor beams - boards that form the attic floor and the ceiling of the lower floor;
Racks - vertical supports that support the rafter system;
Purlins – horizontal supports for rafters;
Crossbars are transverse horizontal elements that tighten the roof slopes together, otherwise they are called puffs;
Rafters - boards that form the main contour of the roof;
Suspension - a suspended rack that supports the tightening and redistributes the load between the rafters;
Lathing - boards or sheets of plywood designed for laying roofing on top of them and transferring the load to the rafter system;
Rabs are boards fixed along the axis at the bottom of the rafters and designed to form a roof overhang.

The cross-section of roofing elements is determined using calculation; the article presents the most commonly used materials in private construction.

Construction of a sloping mansard roof and its differences

As already mentioned, a roof with broken slopes is somewhat different from a simple gable roof. The difference lies in the shape of the opposite slopes: they are not a straight line, but consist of two slopes connected at an obtuse angle. The roof can be either symmetrical or have different shapes of opposite slopes - it depends on the project.

Thanks to the broken shape, the usable volume of the attic space significantly increases. The lower part of the rafters is usually installed at an angle of about 60 degrees to the horizontal, and the support posts supporting these rafters act as a frame interior walls. The upper part of the rafters is most often installed at a slight angle, from 15 to 45 degrees - this allows you to save materials, but maintain the functionality of the roof and its resistance to snow loads.

Vertical posts resting on floor beams, purlins and tie rods connecting them form a parallelepiped that limits inner dimensions attics. To give the structure additional rigidity, struts are installed between the floor beams and the lower rafters. After installing the upper rafters, hanging supports - headstocks - are installed to strengthen the truss and eliminate sagging of the crossbars. To further strengthen the lower rafters, they are pulled together with the racks using contractions. The elements are fastened using nails and bolts or studs.

Calculation of the dimensions of the attic roof

The main condition for a comfortable attic installation is the ceiling height - it should not be lower than 2.5 meters. To ensure such a height of the room, the break line of the attic roof must be at a height of at least 2.8 meters, taking into account the thickness of the insulation layer and internal lining attic, as well as the thickness of the finished floors.

Before you start purchasing materials and building a roof, you need to draw detailed drawing, which will indicate dimensions houses, slope line and attic height.

Drawing - dimensions of the attic roof

Technology for constructing a sloping mansard roof

Install a Mauerlat around the perimeter of the house. IN wooden buildings The mauerlat is the top beam or log. In stone - brick or block - buildings, the mauerlat beams are attached to studs or anchors, fixed in the walls during laying at a distance of no more than 2 meters. The mauerlat is leveled along the inner plane of the wall, and the remaining outside wall is later covered with decorative masonry. Mauerlat timber made from dry softwood usually has a cross-section of 100 or 150 mm. Sawing off timber required length, straighten the anchor pins if necessary and place the timber on top of them. Tapping lightly with a hammer. Indentations from the studs remain on the timber; a hole of the required diameter is drilled along them. You can also mark the timber using a tape measure, but the likelihood of error in this case is higher. Placed on the wall roll waterproofing, you can use regular roofing felt in two layers. The Mauerlat is put on the studs and the nuts are tightened.
For floor beams, coniferous timber with a section of 100x200 mm is usually used. The floor beams are placed either on top of the mauerlat, extending 0.3-0.5 meters beyond the plane of the walls, or in specially designed pockets in the masonry. In the first case, the beams are secured using corners and self-tapping screws. To make the ceilings even, the beams are laid in strict sequence: first, the outermost ones in level, then, by pulling the string, the intermediate ones are aligned along them. The pitch of floor beams is usually from 50 to 100 cm, but the most convenient is a step of 60 cm, which allows you to lay insulation boards without trimming. To level the height of the beams, they are propped up or linings from the board are used. If the beams are placed in special pockets in the masonry, their ends must be processed coating waterproofing and wrapped with roofing felt. Align them in the same way.
Racks are installed on the outer floor beams. The outer racks are made of 100x150 mm timber; the height and installation line of the racks are determined according to a previously prepared drawing. The racks are leveled using a level and plumb line and temporarily secured with jibs in perpendicular directions - along and across the axis of the roof. This will allow you to install the racks without deviation in any direction. The jibs are made from any board and nailed. A string is pulled between the outer drains and the remaining racks are placed along it with a pitch equal to the pitch of the floor beams, that is, on each beam. All racks are secured in the same way as the outer ones. You should end up with two rows of posts of the same height, running parallel to each other.
Purlins from 50x150 mm boards are laid and secured on the racks, the purlins are secured to 150 mm nails and to corners using self-tapping screws. Place crossbars made of 50x200 mm boards on the purlins with the narrow side down - this will increase their rigidity. Since there will be no load on the crossbars during operation, such a section of the board is quite sufficient; however, in order to prevent their deflection and increase reliability during the installation process, when installing the crossbars, temporary supports made of boards no thinner than 25 mm are placed under them. The top of the crossbar is fastened with one or two boards - also temporarily, until the rafters are installed. In this case, the boards should not be placed in the middle of the tightening - there they will interfere with further installation, but retreating about 30 cm. After installing the racks, purlins and crossbars, you get a rigid structure that limits interior spaces attics. To increase its strength, it is subsequently secured with struts and contractions.
Installed from 50x150 mm boards. First, a template is made from a 25x150 mm board - it is easier and faster to process. A board of the required length is applied to the upper purlin, the shape of the cut is drawn directly on the board and it is cut out. Apply the template to the purlin in the places where the rafters are installed, and if it matches everywhere, then the upper part of all rafters can be made according to the template. The lower part, resting on the mauerlat next to the floor beams, is cut out in place each time. The rafters are secured using corners and self-tapping screws and nails.
To make the upper rafters, you need to mark the center of the roof. This can be done using a temporary stand nailed to the Mauerlat and an extreme tie from the end of the roof so that one edge of the board runs along the center line of the roof. The rafters are aligned along this edge. Next, prepare a template from a 25x150 mm board, placing it at the edge of the installed board on the right level and to the purlin on which the lower rafters rest. Mark the upper and lower cuts and cut out the template. Apply it alternately to both sides of the roof, checking how accurately its center is marked. If the rows of racks are made in parallel, then there should be no problems with installing the upper rafters - they will all have the same size.
Perform according to the template required amount rafter legs. The rafters are installed on purlins and connected at the top using overhead metal plates or cutting boards with self-tapping screws. In the purlin, the rafters rest on the notches and are secured to the corners. In order for the rafters to stand straight, they are secured using struts, installed with the lower end on the ties. This is how all the rafters are placed. Attach hanging racks - pieces of board 25x150 mm. The upper edge of the board is fixed at the junction of the rafters, the lower edge - to the tie.
Place struts under the lower rafters from a 50x150 mm board, resting them with the lower oblique cut against the floor beam and securing them to the corners, and attach the upper edge to the side of the rafter leg, nail it to one or two nails, and then drill through hole and secure it to a bolt or stud. After installing the lower struts, remove all temporary supports and posts.
Sew up the gables, leaving door and window openings. If the floor beams are laid in wall pockets, fillies are attached to the lower rafters - boards that continue the line of the rafters and form the roof overhang. When laying floors on top of the mauerlat, the beams already protrude to the required distance, and there is no need for fillers.
, corresponding to the type of roofing - continuous or sparse. Waterproofing is placed on the sheathing and installation of the roof covering, for example, begins.

A broken attic roof usually does not need insulation - only the walls and ceiling of the attic are insulated. The air space created under the rafters ensures good ventilation of the attic, reduces heating of the attic rooms in the summer and provides additional thermal insulation in the winter. Therefore, when sewing up the gables, it is important to leave ventilation windows in the upper part of the roof, above the ceilings of the attic floor.

Video - instructions for constructing an attic roof

Installing an attic in an individual home is a fairly common occurrence. This construction method reduces costs square meter and create a rather interesting room in the under-roof space. In order to properly install an attic floor, you need 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 a volume under the roof that is used to accommodate residential and utility rooms. In this case, the height of the external walls should be no more than 1.5 m in general case, otherwise the space will be considered a full-fledged residential floor.

A do-it-yourself attic is beneficial both during the construction and 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 converted into a separate room for living.

During operation, cost reduction may include the following:

The heated volume of premises is reduced, as a result, there is a reduction in heating costs, which are an impressive item of utility costs.
After completion of construction, the house must be measured by specialists from BTI, after which a passport of the object is issued. It is based on the area values given in it that taxes are calculated and payment is made utilities(subject to connection to centralized systems and the absence of metering devices, which is now practically unheard of). The area of the marsard floor is included in the area of the entire house with coefficients of 0.7 or 0.8 depending on the height outer wall and the angle of inclination of the roof, which allows significant savings throughout the entire life of the facility.

Preparatory stage

Construction should begin with the development of a project or diagrams on which the future structure will be drawn. Most often, the roof that is used for the attic floor is a gable roof, but it is also possible to use a four-slope hip roof. The gable design makes it possible to provide full-fledged windows in the gables.

In the case of using a hip for lighting rooms, it is possible to install only attic window openings. This option may become more labor-intensive in terms of installing roof elements and developing interior interiors. Cost reduction with a hip roof is achieved due to the absence of gables (the savings will be especially noticeable in brick house, where the cost of materials and the work itself for installing wall fences is quite high).

Do-it-yourself attic construction begins with determining the geometric dimensions and shapes of the roof. We have already talked about choosing the type of rafter system for a house (gable, hip), after which you will need to decide whether the slope will be straight or broken. The broken design 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, the optimal roof slope is determined. Its choice depends on ergonomic considerations and the roofing material used, which imposes restrictions.

Before you make an attic, you also need to calculate all of it load-bearing elements for strength and bending, select the composition of the roof pie, perform thermal calculations and decide on materials. More on this below.

Main load-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, pitch and design load. A professional can perform detailed calculations correctly. For private construction, you can use approximate values, but it is best to provide a small margin.
Narozhniki- These are rafter legs that rest on the slopes on one or both sides. The cross section is calculated in the same way as for rafters.
Sloping legs- a design that is used in hip roof. This element serves as a support for the narodniks. The cross-section is taken depending on the load and span; in any case, it should be larger than that of the rafter legs.
Mauerlat- an element that serves as a support for the footrails and transfers the load from the roof to the walls, distributing it evenly. It would be correct to choose a section with dimensions of 100 by 100 or 150 by 150, depending on the complexity of the object. Installation of the Mauerlat is not carried out during the construction of frame and wooden houses, since in this case its role is played by the upper crown of the walls or trim.
Rigel- a beam, which also serves as a support for the rafters, but in the upper part. The crossbar is installed at the ridge of the roof or at a break in the slope, in the case of a broken structure. The cross-section should be taken depending on the conditions; the recommended value is 200 by 200 mm.
Struts, racks, contractions– additional elements for securing elements. They are used to reduce the cross-section of load-bearing structures. Their cross section is most often chosen constructively. It is important to consider the convenience of making connections.

Mansard roof It must be built with your own hands, starting with the selection of sections of all elements of the roof frame. The material for manufacturing is selected taking into account the following conditions:

the wood must be coniferous (pine, spruce, larch);
material grade – first or second;
humidity no more than 15%.

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

Thermal calculations

To keep the house warm, you will need to select the thickness of the insulation. Most often for attic premises mineral wool is used (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 thermal insulation layer from, select its thickness. It is important to consider the height of the rafters. It should always be equal to or greater than the thickness of the thermal insulation. For mineral wool, you will also need to provide a 50 mm thick ventilation gap between the top surface of the thermal insulation 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 an attic roof with your own hands, you can calculate it using heating engineering manually, guided by the joint venture “Thermal protection of buildings.” But it’s better to turn to special programs for help. To correctly calculate the thickness in the Teremok program (freely available on the Internet), you need to know the thermal conductivity of the insulation and the area where the house is being built, the program will find the rest itself.

A do-it-yourself mansard roof is different from a regular one pitched roof only by 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 attic 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;
sheathing;
roof covering;
insulation;
bottom trim.

Assembling the roof frame

Installation begins with the 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 stiletto heels;
on the anchor.

For fragile house wall materials, such as aerated concrete and foam concrete, trimming is carried out monolithic belt which will prevent the walls from collapsing. For wooden and frame houses Mauerlat is not provided.

Next, you need to install the crossbars, if provided. After the supporting structures are laid, the rafter legs are laid out. The fastening of the rafters to the mauerlat can be rigid and hinged. It is better to do it using a notch and fixing it with metal corners on both sides.

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

Before you begin installing insulation in the house, it is necessary to ensure its protection from negative influences environment. To do this, spread a moisture- and wind-proof membrane over the surface and secure the sheathing. After this, the roofing covering is installed, taking into account the recommendations for the selected material. For example, for bitumen shingles you need a continuous sheathing, which is most often made of moisture-resistant plywood.

Installation of thermal insulation

To insulate a house, you need to install insulation without gaps or cracks. For mineral wool, it will be easier to install if the clear distance between the rafters is 580 or 1180 mm. This will allow the material to be laid with a slight spacer, which will prevent cracks from occurring.

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

After laying the insulation, you need to attach a vapor barrier to it from below. After this, the lower sheathing and ceiling lining are installed. For an attic, it is best to cover the frame with two layers of 12.5 mm thick plasterboard followed by finishing.

Many males, having found a family, sooner or later think about purchasing their own home. Someone takes out a mortgage on an apartment, and someone saves money for... But save up for big house Not many succeed and the alternative would be to build a house with.

What is a mansard roof?

The attic can be built from or from a material suitable for you.

It will not be difficult to build an attic, but it requires patience, hard work, suitable materials and availability of tools.

The shape and design of the roof must be included in the design of the house in order to avoid incidents during further operation.

You can build a house with standard project or order it from professionals. In such documentation you will be able to understand where to start and choose the appropriate materials for construction.

Now you can purchase everything you need, but first equip a place to store building materials and tools. The storage place must be dry and so that rain or snow cannot harm the construction material.

It will also be possible to equip a small workshop under the canopy for the manufacture of some parts of the house or roof. For a house made of or who does not have the opportunity to build a full second floor, the choice of an attic roof will be the best option. The house from will budget option. Next we will look at the structure of the attic.

The design elements of the attic are practically no different from gable roofs.

Materials required for the construction of an attic roof

The roof is the outer covering of the roof, it protects inner part attic and can be made of various materials.

For roofing, as a rule, such materials are used:

Stages of building a do-it-yourself attic roof

After becoming familiar with the names of the roof structure, we can continue to further analyze the construction step by step.

First stage

Attic construction always begins from mounting the Mauerlat.

When building on a stone box, you need to think about securing with studs or anchors at a distance of no more than two meters.

At the locations of the anchors, the timber is marked, a hole is made in it and put on the anchors, then the Mauerlat is fixed with nuts to the wall.

To simplify the marking, you need to place the beam on the anchor and lightly go over it with a hammer, after these manipulations there should be traces left, they will be the places for drilling holes.

Second phase

The second stage of the attic construction will be the installation of floor beams.

Actions must be consistent.

First of all, the outer beams are installed at the ends, then the intermediate ones. It is necessary to stretch a nylon cord or scaffolding between the intermediate and outer beams, or you can also use a level. These devices are needed to indicate the plane.

Third stage

We install, align in a vertical position and secure the support posts.

We strengthen it with jibs and make horizontal runs.

It must be taken into account that the racks are placed in equal numbers with the floor beams on two parallel sides of the attic.

Rigidity supporting structure provide horizontal runs.

Fourth stage (rafter system)

We install the rafter structure parts prepared according to the template according to the template and fix them to the vertical supports.

The elements can be fixed using boards or metal plates with holes.

Fifth stage (gables and sheathing)

Z
we sew up the gables, leaving space for them, and attach sheathing boards along the entire roof. This is the most simple work during the construction of an attic.