Roof installation is a complex multi-stage process. In order to independently assemble and install the rafter system, it is necessary to carefully study the methods of connecting the elements, calculate the length of the rafters and the slope angle, and select the appropriate materials. If you do not have the necessary experience, you should not take on complex structures. The best option for a small residential building is a do-it-yourself gable roof.
A standard roof of this type consists of the following elements:
Mauerlat is a timber laid on top of the walls along the perimeter of the building. It is secured with threaded steel rods or anchor bolts embedded in the wall. The beam should be made of softwood and have a square section of 100x100 mm or 150x150 mm. The Mauerlat takes the load from the rafters and transfers it to the outer walls.
Rafter legs- these are long boards with a section of 50x150 mm or 100x150 mm. They are attached to each other at an angle and give the roof a triangular shape. The structure of their two rafter legs is called a truss. The number of trusses depends on the length of the house and the type of roofing. The minimum distance between them is 60 cm, the maximum is 120 cm. When calculating the pitch of the rafter legs, one should take into account not only the weight of the coating, but also the wind load, as well as the amount of snow in winter.
It is located at the highest point of the roof and is most often a longitudinal beam connecting both slopes. From below, the timber is supported by vertical posts, and the ends of the rafters are attached to the sides. Sometimes the ridge consists of two boards, which are nailed to the top of the rafters on both sides and connected at a certain angle.
Racks - vertical beams with a section of 100x100 mm, located inside each truss and serving to transfer the load from the ridge run to the load-bearing walls inside the house.
The braces are made from scraps of timber and set at an angle between the uprights and the rafters. The braces strengthen the lateral edges of the truss, increasing the load-bearing capacity of the structure.
Tightening - the beam connecting the lower parts of the rafters to the base of the truss triangle. Together with struts, such a beam serves to strengthen the truss, increases its resistance to loads.
A bed is called a long beam with a section of 100x100 mm, laid along the central load-bearing wall, on which the vertical posts rest. Lezhen is used when installing layered rafters, when the run between the outer walls is more than 10 m.
The lathing is a board or timber stuffed onto the rafters. The lathing is solid and with gaps, depending on the type of roof. It is always fastened perpendicular to the direction of the rafters, most often horizontally.
If there is no more than 10 m between the outer walls and there is no load-bearing wall in the middle, arrange hanging rafter system. With such a system, the upper ends of the adjacent rafters are cut at an angle and connected together with nails, excluding the installation of racks and a ridge bar. The lower ends of the rafter legs rest on the outer walls. Due to the absence of racks, the attic space can be used to equip the attic. Very often, the function of puffs is performed by floor beams. To strengthen the structure, it is recommended to install the top tie at a distance of 50 cm from the ridge.
In the presence of a central retaining wall, arrangement is more justified layered rafter system... A bed is laid on the wall, support posts are attached to it, and a ridge bar is nailed to the posts. This installation method is quite economical and easier to perform. If the ceilings in the interior are designed at different levels, the racks are replaced with a brick wall dividing the attic into two halves.
The process of installing the roof includes several stages: fastening the Mauerlat to the walls, assembling the trusses, installing the rafters on the floors, installing the ridge, fastening the lathing. Before assembly, all wooden elements are carefully treated with any antiseptic compound and dried in air.
For work you will need:
- timber 100x10 mm and 150x150 mm;
- boards 50x150 mm;
- boards 30 mm thick for lathing;
- roofing material;
- metal studs;
- jigsaw and hacksaw;
- hammer;
- nails and screws;
- square and building level.
In wooden houses the functions of the Mauerlat are performed by the logs of the last row, which greatly simplifies the workflow. To install the rafters, it is enough to cut grooves of the appropriate size on the inside of the logs.
In brick houses or in block buildings, the installation of the Mauerlat is as follows:
The bars of the Mauerlat should form a regular rectangle and be in the same horizontal plane. This will facilitate further installation of the roof and provide the structure with the necessary stability. At the end, markings are made on the beams for the rafters and grooves are cut along the thickness of the beam.
When choosing a hanging truss system, it is necessary to assemble the trusses on the ground and then install them above the ceilings. First you need to draw up a drawing and calculate the length of the rafter legs and the angle of their connection. Typically, the angle of inclination of the roof is 35-40 degrees, but in open, heavily blown areas, it is reduced to 15-20 degrees. To find out at what angle to connect the rafters, multiply the angle of the roof by 2.
Knowing the length of the run between the outer walls and the angle of the rafter connection, you can calculate the length of the rafter legs. Most often, it is 4-6 m, taking into account the eaves overhang with a width of 50-60 cm.
The upper ends of the rafters can be fastened in several ways: overlap, end-to-end and "in the paw", that is, with cut grooves. For fixing, metal pads or bolts are used. Next, the lower and upper puffs are mounted, and then the finished trusses are lifted up and installed above the ceilings.
The end trusses are attached first: using a plumb line, the rafters are set vertically, adjust the length of the overhang and attach to the Mauerlat with bolts or steel plates. So that during the installation process the farm does not move, it is strengthened with temporary jibs from a bar. After installing the extreme rafters, the rest are exposed, observing the same distance between them. When all the trusses are fixed, they take a board with a section of 50x150 mm, the length of which is 20-30 cm longer than the length of the cornice, and nailed it along the upper edge of the ramp. Do the same on the other side of the roof.
The first option: on the rafter leg, at the point of contact with the Mauerlat, a rectangular groove is cut out to 1/3 of the beam width. Having stepped back from the top of the box 15 cm, a steel crutch is driven into the wall. The rafter is set in level, the grooves are aligned, then a wire clamp is placed on top and the beam is pulled close to the wall. The ends of the wire are securely fastened to the crutch. The lower edges of the rafters are carefully cut with a circular saw, leaving an overhang of 50 cm.
The second option: the upper rows of walls are laid out with a stepped cornice made of bricks, and the Mauerlat is placed flush with the inner surface of the wall and a groove is cut out in it for the rafter. The edge of the rafter leg is cut at the level of the upper corner of the eaves. This method is simpler than the others, but the overhang is too narrow.
The third option: the beams of the ceiling slabs are extended beyond the edge of the outer wall by 40-50 cm, and the roof trusses are installed on the beams. The ends of the rafter legs are cut at an angle and abut against the beams, fixing with metal plates and bolts. This method allows you to slightly increase the width of the attic space.
Layer rafters device
1 shows the cut of the rafter struts in the bed, laid along the intermediate supports, and in Fig. 2 - support of the rafter leg on the Mauerlat
The procedure for installing a layered rafter system:
When the main elements are fixed, the surface of the rafters is treated with fire retardants. Now you can start making the lathing.
A 50x50 mm beam is suitable for the lathing, as well as boards 3-4 cm thick and 12 cm wide. Waterproofing material is usually placed under the lathing to protect the rafter system from getting wet. The waterproofing film is laid in horizontal strips from the eaves to the ridge of the roof. The material spreads with an overlap of 10-15 cm, after which the joints are fastened with tape. The bottom edges of the foil should completely cover the ends of the rafters.
It is necessary to leave a ventilation gap between the boards and the film, therefore, first, wooden slats 3-4 cm thick are stuffed onto the film, placing them along the rafters.
The next stage is the sheathing of the rafter system with boards; they are stuffed perpendicular to the slats, starting from the eaves of the roof. The step of the lathing is influenced not only by the type of roofing, but also by the angle of inclination of the slopes: the larger the angle, the greater the distance between the boards.
After completing the installation of the battens, they proceed to sheathing the gables and overhangs. You can close the gables with boards, plastic panels, clapboard, waterproof plywood or corrugated board - it all depends on financial capabilities and personal preferences. The cladding is attached to the side of the rafters; nails or screws are used as fasteners. Overhangs are also hemmed with a variety of materials, from wood to siding.
Video - Do-it-yourself gable roof
A reliable roof is one of the main elements of a private house, which protects the building from rain, wind, snow and other natural phenomena. Without her, it is impossible for my darling to build a house in our latitudes. In addition, today the roof of a private house is more than just a part of the overall structure that protects from the weather. Thanks to a huge selection of roofing materials and design developments, the roof of a country house allows you to emphasize the status and taste of the owner.
When building a house on your own, you need to know and understand many aspects of the construction business, and installing a roof is one of the most difficult and time-consuming. To make the roof of a private house with your own hands, in addition to knowledge about the types of roofs, their design features and installation stages, you will need 3 or 4 more reliable assistants who know a lot about installing roof structures.
Types of roofs of private houses
The design of the roof of a private house directly depends on which type of roof will be used. There are only two types of roofs: pitched and flat. And if a private house with a flat roof for the latitudes of the CIS is more exotic, and such houses are more likely to be found in hotter regions, then the pitched roof of a private house is used everywhere. And there are many reasons for this, the main of which is the presence of a large amount of precipitation. It is about pitched roofs that will be discussed further.
A pitched roof is a structure, the roof plane of which is placed at an angle of more than 10 degrees. Such a roof can be with or without an attic. Among the pitched roofs are distinguished:
- pitched roofs;
- gable roofs;
- hipped roofs;
- hipped roofs;
- mansard roofs;
- hipped roofs;
- steeple roofs.
Important! Shed roofs are most often performed with an angle of inclination of 20 - 30 degrees, gable roofs with an angle of 25 - 45 degrees, mansard roofs can have two inclination angles: 25 - 35 degrees for the upper part and 45 - 60 degrees for the lower part.
Types of roofs of private houses: photo - scheme
Design and construction of the roof of a private house
It is necessary to take care of what kind of roof a country house will have at the stage of creating a private house project. This is due to the convenience of building the house as a whole. Of course, if there is a need to make a completely new roof for an already built house, you will have to develop a new roof project that will harmoniously fit into the overall architectural concept. To create a new roof project yourself, you can use special architectural programs or contact an architectural organization. Today there are a lot of such companies, and in each of them they will be able to offer ready-made projects for the roofs of private houses, competently thought out and time-tested. The second option is preferable, especially if you are a beginner in architecture. And in order not to make mistakes, it is better to leave the work on the roof project to professionals.
Sometimes, to give individuality, designers use not quite ordinary forms of roofs of private houses. These roofs are usually characterized by flowing shapes and rounded edges. But such beauty is achieved due to the complication of the rafter structure, which leads to an increase in its weight.
Private house roof projects - photo:
For those who decided to create a roof project on their own, below is a video tutorial on creating a roof project in the ArchiCAD architectural program:
When designing a roof yourself, you need to know how it works, what it consists of and what materials are best to use. This is very important, because without knowing the name of this or that element, and not understanding what it is for, it will be impossible to make the project correctly.
The main structural elements of the roofs of private houses:
- roof... This is the outer part of the roof, its covering, which performs the function of protecting the entire structure of the house from various natural phenomena, such as rain, snow, etc.
- lathing... The part of the roof structure on which the insulation and the roof are attached. The lathing itself is attached to the rafters;
- ridge run... The top of the entire rafter structure is in the form of a beam to which the rafters are attached;
- rafters... This structural member acts as stiffeners for the entire roof. The rafters are placed at an angle and can be hanging or layered. The basis for hanging rafters is only two extreme supports, often walls. Such rafters work in compression and bending. Most often, hanging rafters are used for mansard roofs. Inclined rafters are supported on two extreme support points and, in addition, on several internal (walls or support beams). Reinforced rafters work only for bending.
Important! In houses with several spans, hanging and layered rafters can alternate in the rafter structure. In places where there are no intermediate supports, hanging rafters are used, and where there are supports, layered ones.
- mauerlat... These are special beams laid along the perimeter at the top of the walls. The entire rafter structure rests on the Mauerlats and is connected to them. Mauerlat is installed flush with the wall and is carefully waterproofed from the side of the wall.
- diagonal ties... To give the entire structure rigidity, the rafters are connected to the Mauerlats and longitudinal beams using diagonal ties, they are also called braces.
- internal supports... Since the roof has a sufficiently large weight, vertical internal supports are used to evenly distribute its load on the structure of the house and give additional rigidity. These beams connect the truss structure and the longitudinal beams.
The entire roof structure is connected to the walls of the house using special pins (ruffs). Support niches can also be cut out under the rafters and tied with 6 mm steel wire.
For the roof truss structure of a private house, a tree is most often used. Of course, metal structures are also created, but wood is most common due to its lower price and availability. Depending on the structure itself, the pitch of the rafters and the calculated loads for the rafter structure, a bar with a cross section of 40x150 mm to 100x250 mm is used. More detailed information is presented in the table:
Table # 1. Characteristics of materials for the roof of a private house
The cross-section of the rafters also depends on their length. Table 2 shows the relationship between the length of the rafters and their cross-section.
Table 2. Cross-sections of rafter legs
The slope of the roof also depends on the type of roof. Table 3 presents the required data.
Table No. 3. Roof specifications
When creating a roof project, keep in mind the following basic rules:
- The calculated snow load on the rafter structure with a slope of less than 60 degrees should be at least 180 kg / m2, and in some cases 400 - 500 kg / m2. If the tilt angle is more than 60 degrees, the load is not taken into account.
- The design wind load is 35 kg / m2. When the slope of the rafters is more than 30 degrees, it is necessary to make an additional correction for the increase in load.
- When designing, there are two important parameters to consider: strength and deformation.
- Metal elements can be used to strengthen the structure. In this case, in order to protect wooden elements from condensation, moisture and decay, they must be treated with a special compound.
The requirements for the roof structure can be found in more detail in the document SNiP "Loads and Impacts".
How to build a roof of a private house
Having created a project and purchasing all the necessary materials, you can proceed to the construction of the roof truss structure. As noted earlier, this type of work will require 3-4 partners. We begin construction of the roof of a private house with the manufacture of the necessary structural elements. Then we proceed to the installation:
- First of all, the Mauerlats are laid and fixed on the longitudinal load-bearing walls. We fix them to the walls with anchor bolts. If provided by the project, we cut support niches in the Mauerlats.
- To simplify the construction of rafters, a template must be made. We take two boards, connect their ends with one nail. We install the free edges of the boards on the Mauerlats. By spreading the ends to the sides, we select the desired angle of inclination and with the help of the transverse crossbar we fix the boards in this position. Do not forget to make sure that the ridge is located strictly in the center of the building. For this we use a plumb line.
- The resulting template can now be applied to the rafter beams and cut at the desired angle.
- After the first rafters have been cut out, we connect them and fix them at the intersection with 3 nails or bolts.
- We raise the connected rafters up and set in place, after which we make the following.
- We install the second rafters at the end of the building and fix them.
- Now we take the cord and pull it between the installed rafters, while making sure that the stretched cord is strictly along the horizon. If necessary, lower one of the installed rafters a little.
- We make the rest of the rafters and install them along a stretched cord with a step indicated in the project.
- To strengthen and increase the stability of the structure, we install and fix support posts and diagonal braces.
Important! For fastening and fixing all structural elements, nails are usually used. But today, stamped metal parts can also be found on the market, which somewhat simplify the process of erecting a truss structure.
How to insulate the roof of a private house
Having completed the construction of the truss structure, you can proceed to the insulation of the roof. These works are carried out just before the roof is laid. But all calculations and the choice of materials for insulating the roof of a private house are carried out at the design stage. Roof insulation is important for several reasons. Firstly, it protects the entire structure from large temperature fluctuations, which affects the durability of the materials used. Secondly, with proper thermal insulation, the dew point shifts closer to the outer edge of the roof, and thus a favorable and comfortable microclimate in the house is formed.
When choosing materials for roof insulation, one should focus on the following characteristics:
- resistance to temperature fluctuations;
- moisture resistance;
- low coefficient of thermal conductivity;
- environmentally friendly materials that do not emit harmful substances;
- low flammability;
- the density of the material is not more than 250 kg / m3.
There are many different thermal insulation materials on the market today. Among them, mineral wool is especially popular, but experts recommend paying attention to another material - foamed glass. Any of these materials will be the right choice.
In order for the roof insulation to be of high quality, the following must be done:
- On the inside of the rafters, we lay the vapor barrier and fix it to the rafters with staples. We overlap the sheets of vapor barrier material and glue them with tape. We make sure that the vapor barrier material tightly fits all the rafters.
- Now, on the rafters with a step of 50 cm, we stuff wooden planks, which will hold the thermal insulation on themselves.
- We carefully cut the thermal insulation so that it lies close to the rafters and does not leave cracks, and we put it in place.
- To ensure reliable protection of thermal insulation from moisture, we lay a layer of waterproofing on the outside of the rafters. We fill the lathing strips on top, on which the roof will subsequently be laid. These strips also act as fasteners for waterproofing. It remains to lay the roofing materials, and the roof for the country house is ready.
How to cover the roof of a private house
The market offers a variety of roofing materials and it can be difficult to make the right choice. To facilitate this task, you must be guided by the following parameters:
- Roofing material weight. It should be no more than 250 kg / m2.
- Durability. Everything is simple here, the longer the better.
- Fire resistance. A non-combustible material will be preferred.
- Environmental friendliness. The internal microclimate of the house will depend on how clean and natural the roofing material is.
- Simplicity of styling. The easier and easier to install the roofing material, the less time-consuming and easier it will be to repair the roof.
- Aesthetic appeal.
Today, metal tiles, ceramic and cement-sand tiles are very popular. These roofing materials, combined with good noise and heat insulation and a solid roof structure, will create a reliable roof. As for ordinary slate, it is still one of the most used roofing materials, but due to its environmental friendliness, slate is gradually losing popularity. Separately, I would like to highlight bituminous and polymer-bituminous materials. They belong to the class of soft roofing materials, and the price makes them affordable for everyone. Unfortunately, the level of their flammability is poor, but subject to all fire safety standards, they can be a reliable roof. For those who are not constrained in funds, experts recommend turning their attention to shale materials. This type of roofing has been known for a very long time, and today it is becoming even more popular due to its natural origin, durability, non-combustibility and very high attractiveness.
More and more people are striving to make their cherished dream come true - to get out of the multi-storey urban development into their own home. The acquired suburban area quickly turns into a construction site. And, in accordance with the natural mentality of most Russian men, work on the construction of a new home is very often carried out on their own. And, many of the amateur craftsmen do not have much experience in this area at all, they learn literally on the go, look for useful and reliable information in available sources, including on the pages Internet resources dedicated to construction. We hope that our portal will provide them with serious assistance in this matter.
So, after the walls of the house have been raised on a reliable foundation, it is necessary, without delaying with this, to proceed to creating a roof and laying a roofing covering. There can be many options here. And one of the most commonly used is the gable roof structure. It is not as difficult in calculations and installation as some others, that is, even a novice builder should cope with it. Therefore, the topic of this publication is the construction of the roof of a private house with your own hands using the example of a gable rafter system with
It should be noted right away that the article does not provide a ready-made "recipe". The aim is to demonstrate the principles of calculating a gable roof and the sequence of its construction. And a master who has the appropriate estimate must already bring the recommendations received to his own, specific construction conditions.
General information about the construction of gable roofs
The basic principle of the construction of a gable roof is probably already clear from its name. The roof of such a roof forms two planes, converging along the ridge line, and resting on the long walls of the house (along the cornice lines). From the end sides, the roof is limited by vertical gable walls. As a rule, both along the line of the cornices and along the pediment, the roofing is somewhat released outside, outside the building in the plan, so that overhangs are formed that protect the walls from direct atmospheric precipitation.
Most often, slopes have a symmetrical shape. Sometimes they resort to asymmetry, when the slopes are located at different angles to the horizon and, accordingly, differ in their length. But these are isolated cases, and will not be considered within the framework of this publication.
The height of the roof in the ridge, that is, the steepness of the slopes can be different - it all depends on the planned use of the attic space, the architectural idea of the owners, the type of roofing used.
Gable roofs have proven to be highly reliable. And the relative simplicity of the design makes them so popular among private developers.
The external similarity of gable roofs does not at all mean the uniformity of the design of their rafter systems. It is precisely in this matter that there can be significant differences, depending both on the size of the building and on its design features.
By the principle of structure, gable roof truss systems can be divided into two groups:
- If the rafters rest on the outer walls of the building and are interconnected in a ridge knot, then such a system is called a hanging system.
To give additional rigidity to such a structure, the rafter legs of each pair are reinforced with horizontal puffs (contractions). Vertical posts supported on floor beams or diagonally installed struts can also be used.
- In the case when the structure of the house assumes the presence of a main wall inside the building, a layered rafter system is often used. The name speaks for itself - the legs "lean" on the racks, which, in turn, rest on the bed, laid along the top end of the capital inner walls. And, this wall can be located both in the center and offset from it. and for large buildings, two internal walls can also be used as supports. Several examples of layered systems are shown in the illustration below.
- However, a kind of "hybrid" of both systems is often used. The rafters in these cases, even without the presence of an internal partition, also receive support on the central post in the ridge assembly, which, in turn, rests on powerful floor beams or on horizontal puffs between the rafter legs.
In any of the systems, especially in cases where the rafter legs are of considerable length, additional reinforcement elements are used. This is necessary to exclude the likelihood of deflection of the timber or even its fracture under the action of loads. And the loads will be tested here. First of all, it is static, due to the weight of the rafter system itself, lathing, roofing and its insulation, if it is provided for by the project. Plus, there are large variable loads, among which wind and snow loads come first. Therefore, they strive for the rafter legs to provide the required number of support points in order to prevent possible deformation.
Some of their reinforcement elements are shown on the rafter system design diagrams:
The illustration above shows an example of a layered rafter system:
1 - Mauerlat. Usually it is a bar rigidly fixed to the upper end of the outer walls of the building. It serves as a support and base for securing the lower part of the rafter legs.
2 - Lezhen. A bar fixed to the inner partition of the building.
3 - Rack (another name is the grandmother). Vertical support from the bed to the ridge girder.
4 - Ridge run. A beam or board that connects the center posts and serves as the basis for securing the upper ends of the rafter legs.
5 - Rafter legs.
6 - Braces. These are additional elements of reinforcement, by means of which it is possible to reduce the free span of the rafter leg, that is, to create additional points of support for it.
7 - Sheathing to match the selected roofing.
Prices for fasteners for rafters
rafter mounts
In systems of a hanging type, reinforcement is performed by installing horizontal ties (item 7), which rigidly bind the opposite rafter legs, and thereby reduce the bursting load acting on the walls of the building. There may be several such puffs. For example, one is installed in the lower part, closer to the level of the Mauerlat, or even almost flush with it. And the second is closer to the ridge knot (it is often also called the crossbar).
With a long rafter length, it may also be necessary to use vertical struts (pos. 3) or diagonal struts (pos. 6), and often both of these elements in combination. They can be supported by floor beams (pos. 9), as shown in the illustration.
It should be correctly understood that the shown schemes are not at all a dogma. There are other designs of truss systems. For example, the fastening of the lower part of the rafter legs is often applied not to the Mauerlat, but to the floor beams placed outside the walls of the house. Thus, the required
In the roofs of large houses, more complex schemes can be used. For example, the rafters are connected by additional longitudinal girders, which, in turn, are supported by vertical posts or struts. But taking on the creation of such complex systems without well-established experience in this area is hardly reasonable. Therefore, we will restrict ourselves to considering the construction of gable roofs, which are quite simple in design.
Calculating the parameters of a gable roof
The construction of the rafter system and the arrangement of the roof on its basis should always begin with the necessary calculations. What tasks are being set in this case?
- First of all, it is necessary to understand the relationship "ridge height - steepness of the roof slopes."
- After that, it will be possible to accurately calculate the length of the rafter legs, both "clean" and full, that is, taking into account the planned eaves.
- The length of the rafters and the estimated pitch from the installation will make it possible to determine the cross-section of the material suitable for their manufacture, taking into account the expected loads on the roof. Or, conversely, based on the available material, choose the optimal step and place additional support points - by installing the reinforcement elements mentioned above.
The listed parameters will allow you to draw up a diagram and a drawing of the rafter system as accurately as possible, and correctly arrange all its elements. According to the existing scheme, it will be much easier to calculate how much and what material will be required for installation.
- You will need to know the total area of the roof slopes. This is necessary for the purchase of roofing material, hydro and vapor barrier membranes, insulation, if thermal insulation of the roof is planned. In addition, the area parameter is also important for determining the amount of material for arranging the battens for the selected roofing.
To make it clearer in the course of the presentation of the calculation procedure, the main quantities are schematically shown in the illustration below:
D- the width of the house (the size of its gable wall);
VC- the height of the roof in the ridge above the plane of the Mauerlat or floor beams, depending on what the lower ends of the rafter legs will be attached to;
a- the angle of steepness of the roof slopes;
WITH- the working length of the rafter leg, from the ridge to the Mauerlat;
ΔC- lengthening the rafter leg to form the planned cornice overhang;
NS- the step of installing the rafter legs.
Let's start examining the above issues in order.
The ratio of the steepness of the slopes and the height of the roof ridge
These two quantities are closely related. AND Totheir calculation you can approach from various angles, taking certain criteria as the starting point.
- For example, the owners see their house with a high roof, somewhat vaguely reminiscent of the Gothic style of architecture. It is clear that with this approach, the height of the roof in the ridge and, accordingly, the steepness of the slopes increases sharply. However, it should not be forgotten that such roofs experience maximum wind loads due to their pronounced "windage". But the snow on such slopes will practically not linger. So it is worth considering these two factors initially. Perhaps for an area closed from the winds, but with a predominance of snowy winters, this option will generally be the most acceptable.
There are pronounced steep slopes and a high ridge - snow on such a roof does not linger at all, but the effect of the wind becomes maximum But do not forget that the longer the rafter legs, the more difficult the system itself will be in the arrangement, which will require a lot of reinforcing parts.
- Another consideration for making the roof taller is very often the desire to have a functional attic space, up to the equipment of a full-fledged living room in it.
For an attic room, a broken rafter system is certainly preferable. But if, nevertheless, a gable is planned, then a lot of space is eaten up by the corner zones along the line of connection of the rafters with the Mauerlat. We have to increase the steepness of the slopes (see above).
True, there may be an acceptable solution here as well. For example, the Mauerlat is not located at the floor level, as in the "classic" version, but on the side walls, which are deliberately raised above the floor to a certain height. Then, even with a large steepness of the slopes, and without much complicating the design of the system, magnon will achieve very spacious attic rooms.
Prices for metal tiles
metal roofing
By the way, it is this option that will be considered below, when the story goes about the installation of the rafter system.
- It happens that the owners of the future house, on the contrary, decide on the minimum steepness angles of the roof. This can be caused by structures for saving materials, the lack of the need for usable space in the attic, the peculiarities of local conditions - for example, very windy, but not particularly snowy terrain.
True, with this approach, one must not forget that any roof covering has certain lower boundaries of the steepness of the slopes. For example, if you plan to lay piece shingles, then it is necessary to provide an angle of steepness of at least 20, and for some models even 30 degrees. So if the plans already have this or that roof covering, its characteristics should be correlated with the height and steepness of the roof.
So, how is the calculation done. As a constant value - a constant, we have the width of the house along the pediment wall ( D). Using the well-known trigonometric formula, it is easy to find the height ( VC), starting from the planned steepness of the slopes (angle a).
Sun = 0.5 × D × tg a
It is clear that to calculate a symmetrical gable roof, half the width of the building is taken, that is 0.5 × D.
One more nuance. When calculating according to this ratio, the height difference is taken to be the difference between the heights of the ridge point and the Mauerlat plane. That is, the excess over the attic floor is not always meant - this should be borne in mind.
The mentioned formula is included in the proposed calculator.
Calculator of the ratio of the steepness of the slopes of a gable roof and the height of its ridge
The roofs of private houses are divided into several different categories, depending on the shape, structural elements, the complexity of the device, and more. The choice of the type of roof during the construction of a building should be taking into account many factors: the amount of precipitation in a particular area, the strength of the structure, wind load, the arrangement of living rooms in the attic, etc.
The roof of the house performs several important functions at once:
- provides hydro and sound insulation;
- creates a barrier from the wind;
- acts as a thermal barrier.
The durability of the structure depends on the quality of the structure itself and the roofing material. Also, these indicators affect the cost of heating rooms inside the building.
Flat and pitched roofs
The roofs of houses can be flat and pitched (inclined).
Depending on the architecture of the building, the appropriate roof structure is selected even at the design stage. Drawings are created, and calculations are carried out, taking into account all the features of this architectural structure. The layout of the roof - the attic or living quarters - is also thought out in advance.
Country cottage with a flat roof Flat structures are found mainly in countries that receive insignificant annual rainfall. Since with abundant rainfall, water will accumulate on such a roof, and it can begin to leak. In the vastness of our country, pitched roofs are used in the construction of buildings. The plane of such structures is located at a certain angle, usually it is more than 10 degrees and depends on the abundance of precipitation falling during the season in a given region.
All other advantages and disadvantages of flat roofs can be learned in more detail in this special video.
Much more often they use projects of roofs of private houses with an inclined structure, which can have several slopes at once.
Attic and attic roofs
According to their design, roofs can be divided into attic and attic. For those who are not attic, the load-bearing elements of its structure are at the same time the overlap of the upper floor of the house. They can be ventilated or non-ventilated. Attic roofs have an attic floor that separates their structure from the living quarters.
Roof purpose
When choosing a roof for a house, you should decide in advance how its space will be used: as a simple attic or living room. These moments significantly affect which shape and type of roof is suitable for your home.
The main types of roofs of houses in shape
Roof structures of private houses in their form can also be divided into several types:
- single-slope,
- gable,
- hip,
- multi-pliers,
- attic,
- tent,
- domed,
- conical,
- flat.
The main types of roofs for private houses For pitched roofs, the angle of inclination usually does not exceed 20-30 ⁰. The planes of mansard roofs are set at an angle of 45-60⁰ in the lower part and 25-35⁰ in the upper part. For conventional gable structures, this figure is in the range of 25-45⁰.
Hip roofs offer 4-8 planes for better rain and snow removal.
Beautiful roof structures of private houses are obtained by combining several gable elements or types, however, maintaining such structures in good condition and installing them is not easy.
Shed roof
It has a fairly simple form. At the same time, in the arrangement of private residential buildings, this type of roof is extremely rare, since with such a design, the load on the rainwater drainage system increases significantly, and they just do not look very beautiful.
Detached house with a pitched roof In most cases, such roofs are used in the construction of small width outbuildings. If you nevertheless decide to equip just this type of roof, then you will need a reinforced drainage system with a higher capacity.
Gable roof
Also with a very simple structure, they are the most common type of roof for private low-rise buildings. When arranging it, you can use almost any roofing material.
Diagram of the device of a simple standard gable roof of a private house Hip (gable) roof
The hip (hipped) roof is more common in the southern regions. With this version of the roof arrangement, the attic has no gables, and the dormer windows, in most cases, are located at the intersection of the ridge with the hip ribs. By its design, a hip roof is much more complicated than a gable roof, therefore it is more often used in cases where a building needs to be aesthetically pleasing.
The structure of the hip hipped roof of the house Multi-gable roof
The multi-gable roof type is distinguished by an impressive number of different versions, depending on the size and number of gables (gables). It is recommended to trust its construction only to experienced professionals, since its arrangement is accompanied by the formation of sunken corners, which require very precise and accurate roofing work.
Construction of a multi-gable roof of a house Roof roof
As a rule, they are equipped in cases where the use of the attic for living quarters is expected. This type of roof has a broken profile and, accordingly, is somewhat difficult to manufacture. It is often a type of multi-gable and gable roof.
Sloped mansard roof scheme Other types of roofs for private houses
In addition, conical, domed and combined types of roofs are quite common. Conical and domed roofs are often used as decorative or individual elements of more complex building structures. The combined type is one of the most common types of roofs, since it combines several elements of separate types at once.
Private country cottage with a conical roof The choice of the type and shape of roofs for private houses
When choosing the shape and type of roof, it is necessary to take into account the factors on which its performance depends. First of all, you should pay attention to the slope of the roof. In snowy areas, it is advisable to select structures with simple and steep shapes, since snow will practically not accumulate on such.
In areas with strong winds, the strength of the wind load must be taken into account when choosing.
The higher it is, the greater the angle of inclination, area and height of the roof. In addition, it is required to take into account the fire protection requirements for roofs.
Read also
Insulation of the roof of the house
Glass roofs for private houses
Many owners of country cottages dream of enjoying the view of the starry sky. Roof projects for private houses can involve both partial glazing and the arrangement of a transparent dome. Glass roofing is installed on the terrace, balconies, veranda.
The shape of the roof for private houses and various types of structures is performed in the form of an inclined plane, dome, sphere. Panoramic glass roofs are mounted on several slopes, which significantly increases the viewing area. During the installation of such a structure, it is necessary to use reinforced aluminum and steel profiles.
Glass roofs for private houses have their own distinctive features. When designing a structure, it should be borne in mind that it will be necessary to periodically wash and repair glass. The roof, like the windows, will eventually tarnish from dust and precipitation on its surface. It is also advisable to install a heating system on the glass so that ice and snow do not accumulate on them in cold weather, and you can enjoy the views.
Materials for transparent roofs
To create transparent and, at the same time, warm and safe roofs are used:
- glass triplex,
- plexiglass,
- polycarbonate,
- transparent slate.
Ordinary glass is not used to create transparent roofs due to its high fragility; if broken, the fragments can harm human health.
- Triplex is the safest material for creating a safe coating.
- Laminated glass also does not shatter when broken, however, the light transmittance is not very high and it is very thick.
- Reinforced glass is sometimes used for roof glazing. If the glass breaks, the shards will remain in the wire mesh frame.
- Plastic translucent materials - polycarbonate, plexiglass and slate have excellent properties (lightness and high strength), which make them possible to use them to create complex sliding structures.
Construction of a simple roof of a wooden country house
Roof projects usually involve maximum use of the attic space, for which the upstairs room is expanded and insulated. The resulting usable attic area can be used for housing.
The roof structure of a wooden house consists of a frame and a roof. The roof frame consists of load-bearing and fastening elements. The main part includes: rafters, mauerlat and crate. Important additional elements of the frame are transoms, struts, struts, etc. They add rigidity to the structure.
Construction of roof elements of a wooden house The height and volume of the resulting room depend on two factors: the angle of inclination and the number of slopes. Typically, projects for the roofs of country houses suggest a gable broken shape. This design is most convenient for human life. Sometimes on the second floor the plan includes a balcony. It should be taken into account that at the maximum point, the height of the attic floor should not be less than 2.2 m.
The interior of a conventional gable roof can also be used as a living area. Bedrooms or an office are located here. At the same time, the height of the middle part of the room should not be less than 1.8 m.
The roof consists of materials that provide heat, hydro and vapor barrier.
When installing a roof, special attention is paid to the choice of insulation. It is also worth dwelling on a roofing material that is more suitable in terms of characteristics for your structure.
Detailed diagram of the device of the roof of a wooden house - Waterproofing provides protection from precipitation, so the coating should not have any damage on its surface and even very small holes and holes.
- The vapor barrier ensures that there is no condensation, which can cause dampness in attics and mansard rooms. Also, excluding the dampness of the wooden structure will allow the inclusion of window openings in the projects of the roofs of country houses, which will allow for ventilation. The location and number of vents affects the ventilation of the attic and its illumination.
- produced depending on its design features. Rigid material is laid on monolithic floors. A screed is made on top and the floor covering is mounted. On wooden structures, the following are laid: a vapor barrier material, insulation, a rough floor is made and only then the floor covering is installed.
The construction of a roof is required for absolutely any building, and the final result depends on how much the developer is familiar with the basics of erecting such structures, expressed in its reliability, durability, and the ability to withstand any whims of the weather. The structure of the roof is not as simple as it might seem to someone at first glance. It consists of many parts and elements, requires a competent calculation and the same execution.
Features of some types of roofs
There are 2 main types of roofs:
- pitched;
- flat.
Both structurally and in terms of the materials used, the differences between these types of roofs are significant.
Flat roofs are usually arranged on top of industrial buildings, as well as on multi-storey buildings, while pitched roofs, as a rule, are crowned with low-rise buildings - 2-5-storey buildings: cottages, summer cottages, some Khrushchevs and other types of structures. The most common type of pitched roof is the classic gable roof.
With sufficient desire and skills, flat roofs of small structures such as garden houses, gazebos, and sometimes private houses, can well be erected with your own hands, even if you decide to carry out the entire list of work alone.
As for the device of a pitched roof, it will be quite difficult to act here with one pair of hands, and if possible, it would be better to invite 1-2 assistants to help.
Required roof slope
The device of the roof of a private house, as well as buildings of a different kind, presupposes a slope. The roof slope is chosen, guided by the following set of rules:
- It should not be forgotten that the value of the chosen slope is directly proportional to the total cost of the roof. With an increase in the slope, the consumption of materials also increases, and, consequently, the overall estimate. Therefore, when choosing a slope, it is necessary to maintain a balance between all the requirements and components. For gable slopes, the optimal roof slope limits are 20-45 degrees, for single-slope ones - 20-30 degrees.
External roof structure
The load-bearing elements of the roofs are made of boards, beams and logs. Based on the materials used, the method of joining the individual roof elements is determined.
The outer structure of a complex hipped roof consists of the following elements:
- stingrays;
- skate;
- hips;
- grooves;
- pediments;
- pediment overhangs;
- gutters;
- drain pipes;
- chimney pipes.
Internal roof structure
As for the internal structure of the roof, here the main role is played by the structure of the roof frame, which is represented by the supporting roof truss system, consisting of rafters, lathing and Mauerlat.
In addition, fasteners such as posts, transoms, struts, struts and others can be included in such a structure. All of them are applicable to give the truss more rigidity.
The composition of the roof supporting structure is as follows:
- racks;
- crossbars;
- rafter legs;
- overlapping;
- struts;
- mauerlat;
- grandmother;
- spacers;
- runs;
- tightening;
- beams.
The device of the rafter system
Rafter system The need for the use of additional structural elements appears with an increase in the span. The rafter truss is formed by the individual parts of the roof, which are connected to each other.
The truss is based on the use of triangular fasteners, since this figure gives the structure the greatest rigidity.
Wooden beams, which are laid in the cutoffs of the outer walls, are called Mauerlat. It serves as a base for load-bearing rafters. The Mauerlat is attached to the walls by means of metal brackets and tie bolts.
The roof construction scheme can provide for the use of one of two types of rafters:
- hanging;
- layered.
Reinforced rafters are applicable in roofs of houses with medium retaining walls. The span between the supports is usually up to 4.5 m, and with an increase in the length of the spans up to 6 m, struts are installed under the rafters.
Do-it-yourself roof rafters of this type rest against the Mauerlat with their lower ends, through which the load from the weight of the roofing structure is transferred to the wall.
Such a support scheme provides for the transfer of not only vertical, but also horizontal loads on the walls. The load appears due to the operation of the rafters against the rafters, therefore, the use of layered rafters is recommended in buildings with massive walls that are able to perceive and withstand the spacer load emanating from the rafters.
Hanging rafters are used less often, since they require even more careful manufacturing of nodes, especially screeds. The advantage of such rafters is the absence of horizontal load transfer to the walls, as well as their ability to cover large spans.
Roof insulation and waterproofing
The device of a continuous sheathing for a soft roof After the construction of the roof frame is over, they move on to its insulation and waterproofing. Particular attention should be paid to materials used for insulation and waterproofing of the roof and located in the under-roof space.
Mineral wool basalt slabs, expanded polystyrene slabs and glass wool at least 15 cm thick can be used as a heater. They will keep the attic warm in winter and prevent it from overheating in summer.
To protect the insulation from moisture, it is covered with a waterproof film that forms a continuous waterproofing layer. With a large amount of moisture, it will be able to drain through the film onto the street, and with a small amount, it can evaporate and be removed with an air flow to the street through the roof ventilation system.
This system is very effective against dampness.
The air-conducting sub-roof space is formed by such structural elements as battens and counter battens.
The counter-lattice is nailed longitudinally over the rafters. In the transverse direction, a crate is attached to it, which is necessary for laying the roofing covering.
For roll-type roofing materials, the lathing is performed in the form of a continuous flooring, for piece roofing materials - in the form of a lattice.
Roofing decking
Roofing installation rules:
- Any type of covering is laid in dry and warm (moderately warm) weather.
- The roofing material is lifted onto the roof carefully one sheet at a time.
- Decking starts from the bottom row, moving from right to left.
- The material is hardened using various methods depending on its properties. For some types, nails are applicable, for others - screws or special clamps.
Advice! In no case should you save on fastening, as this is fraught with inevitable roof leaks.
- If there is not enough length of material for laying the last row, the sheets are usually cut with a grinder to the required length.
- The installation of roofing material implies the obligatory observance of overlaps of a certain length for each roofing material. The amount of overlap depends not only on the material, but also on the slope of the roof. The smaller the slope of the roof slope, the greater the slope must be provided.
Among other things, the roof construction scheme assumes the presence of other elements on it: windows, stove, fireplace or ventilation pipes, valleys, ridge, fencing grilles, antennas, snow retention and drainage systems.
Each of them can be provided both to improve the appearance of the structure and to protect the roof.