The roof of the house is one of the main components of the house. It represents the upper structure of the building, without which it is difficult to imagine comfortable living. The main functions of the roof are protection from snow, rain and other precipitation, as well as keeping warm during the cold season and protecting against overheating during the summer months. In our years, there is a wide variety of roofs for every taste and budget. However, the most common and popular at all times are gable roofs, which are versatile, inexpensive and easy to install. We will talk about how to correctly make a gable roof with our own hands in today's article.
The gable roof structure is the most common in private construction. As is clear from the name of this type of roof, it is made in the form of two slopes or, more simply, in the form of a triangle. Such roofs are easy and quick to install, they are durable enough and appearance finds many admirers, as it combines the look of a Russian hut and a modern building. Possessing necessary knowledge, you can do it yourself using the available tools.
The rafter system of a modern two pitched roof consists of many elements, each of which evenly redistributes the weight of the structure and competently transfers it to the walls of the house. The figure below shows the construction of a gable roof of a house with its main nodes and elements of the rafter system.
Let's analyze each of the elements shown in the diagram separately:
This roof scheme is universal for many buildings, but depending on the complexity of the structure, special elements can be added here to give stability and rigidity to the entire rafter system.
The choice of an acceptable angle of inclination of the roof is a significant task, but for many builders it fades into the background, which is not true. The so-called gable structures with straight slopes are considered standard. Optimal angle the slope of the gable roof is on average 30 ° -45 ° (the angle at the base of the isosceles triangle is taken as a basis).
The choice of the angle of inclination will determine how well the upper part of the house will withstand the following factors:
The first two points must be taken into account with special care, since a miscalculation in choosing a roof slope can cost large financial losses and health in the event of a collapse.
Example: the larger the angle, the less the load on the roof from precipitation, however, the threat of wind damage due to the created wind increases (the roof can simply be blown off). The noise effect will also increase if metal is chosen as the roofing material.
Thus, when designing a roof and choosing an angle of inclination, it is important to know in advance what kind of roofing material you will be covering it with. As you can see, the minimum angle of inclination of a gable roof can be 6 °.
Most of the rafter systems for gable roofs are divided into two main types - hanging and layered. The first type is the most common. Let's take a closer look at both types.
This type of roofing structures is used exclusively when the walls of the house are at a distance of up to 10 m from each other and there are no supporting ceilings between them. The rafters (legs) are joined only with the side parts of the house in the form of a Mauerlat. Minus a gable roof with hanging rafters there is a possibility of its damage due to the bursting load, since in this case there are no stretch marks between the rafters.
The difference between layered structures is the presence of an additional support in the form of a wall or other support. Naslonnaya rafter system installed with supports that are fixed to intermediate walls. This design allows you to close large spans without compromising the rigidity of the entire rafter system.
Separately, it is worth talking about several more types of gable roofs. By design, a gable roof can be made in the following versions:
The differences between these structures are clear from the name. Depending on the project of your home and on design solutions the roof can be asymmetrical, that is, have different angles of inclination at the base. Such a roof is a little more difficult to install than a conventional symmetrical roof, which has an isosceles triangle at its base, but experienced master it will not be difficult to build such a structure.
A gable sloping roof is also very common. The rafters of such a roof are, as it were, a little broken off at the base. Such roofs practically do not retain precipitation on themselves and allow you to win in the attic space for.
Often, novice builders, before designing and calculating the purchase of material, have questions about how to find out the length of the rafters of a gable roof. For this, it is important at the design stage to know what the width of the building will be, for the selection of rafters standard size so that you do not have to splice them, sacrificing their carrying capacity. Along with this, one must not forget about the angle of inclination of the roof. All of these factors will ultimately affect the length calculation.
So, to calculate the length of the rafters of such a roof, you need to divide the triangle formed by the rafter system into two right-angled triangles. Further, knowing the width of the building and the angle of inclination of the roof, you can determine the height of the ridge of the gable roof. Knowing the two legs of a right triangle and using the Pythagorean theorem, you can calculate the hypotenuse of each right triangle, which is the required length of the rafters of our roof.
As a result, to determine the final length, another 30-50 cm must be added to the obtained value to ensure the overhangs of the roof.
All the calculations carried out to determine the height of the ridge (it is the height of the pediment) and the length of the rafters are clearly shown in the image:
From the foregoing, we can conclude that a gable roof is the cheapest and most versatile type of roof for a private house. There are examples when, with the help of improvised means, people erected a gable roof on their own alone. Nevertheless, we advise you to use the help of specialists in such matters, because a well-made roof over your head means comfort and coziness in the house.
The first and fundamental stage in the construction of a gable roof is its design. We have already said that the load taken by the roof will depend on the choice of the angle of inclination of the roof, and, as a result, the choice of roofing material that can withstand precipitation and loads from these precipitation and wind.
At this stage, drawings of the structure of the future roof are created and all the necessary calculations are carried out. This is necessary, first of all, in order to have an idea of general view roof dimensions and dimensions, and to accommodate all anticipated maximum loads.
After the design, you will have the entire package of documents in your hands, which will indicate all the dimensions of the future roof, its area for the purchase of roofing materials, the full range of lumber used in the construction. The presence of a list with the nomenclature of sawn timber will allow you not to spend extra money on its purchase, since when building a roof, sawn timber is the main cost item.
After all have been completed design work, go directly to construction work. When carrying out work with your own hands, half of the budget is saved, which could have gone to pay the builders. At the same time, it is important to remember that all norms and rules are followed so that the end result meets expectations.
The Mauerlat takes all the load from the roof and transfers it to the walls, so a fairly thick and strong beam is chosen as the Mauerlat. The thickness is chosen based on the thickness of the wall on which it rests. As a rule, they tend to choose the thickness of the Mauerlat bar equal to or close to the wall thickness.
It is necessary to lay the Mauerlat flush with outside walls by firmly joining them together. To connect the Mauerlat to the wall, even at the stage of wall construction, anchor bolts or wire are laid (poured into the armored belt). If a wire is used as a fastener, then after laying the timber, it is tightly tied around with this wire and remains firmly fixed in this form. If anchor bolts were walled into the wall, through holes are pre-drilled in the Mauerlat, with which the bar is pushed onto the bolts and tightened from above with nuts with wide washers.
It is also important not to forget to lay a layer of waterproofing material in the form of a gasket between the wall and the Mauerlat. Roofing material or similar materials are usually used as waterproofing. Read more about fixing the Mauer in this video.
After the base is prepared, proceed to the assembly of the gable roof rafter system. The installation of rafters can be done in several ways: install the rafters directly on the roof or perform some structural elements on the ground, and then lift them with special equipment to the installation site. Correctly setting the rafters on a gable roof with your own hands without the help of a partner is quite problematic, so it is better to use help so as not to make a mistake and not to nullify all efforts.
To make it easier to fasten the beams, it is worth marking the attachment points on each wall and connecting the opposite walls with beams (legs), on which the racks will be installed to support the rafters. A ridge bar is installed on the racks, which is a guide for installing the rafter system. In order to connect the rafters as accurately as possible, so that the entire skeleton of the rafters is the same, use templates. This way you can avoid dips and distortions in the roof.
After installing the ridge bar, they proceed to the most critical part - the installation of the rafters (already fastened together or separately). In this case, it is important to constantly monitor the level and evenness of the installation. The rafters are fastened to each other, as a rule, on nails or with the help of iron brackets. Common schemes for placing rafters on a gable roof and attaching them to each other are shown in the figure below.
After completing the roof frame, it is required to install auxiliary fasteners to improve the rigidity of the roof. For this, struts and middle skates are installed.
We invite you to watch a video that clearly shows the installation of rafters with your own hands for a gable roof.
The lathing of a gable roof in the simplest case is the installation of transverse boards on the rafters for laying roofing material on it. But usually modern roof is a more complex cake of different layers.
After installing the lathing, the roof is covered with a layer of waterproofing, the layers of which are mounted with an overlap on top of each other, and the joints are fastened with tape.
The next step is to secure the counter battens - slats fixed at an angle of 90 degrees to the main batten. This is to provide a ventilated gap in the roofing pie to get rid of moisture.
At the final stage of installation of a gable roof, they are laid roofing, the choice of which, as mentioned at the beginning of the article, depends on both several factors, including the financial component
External work on the installation of the roof ends with the arrangement of the gables, if they are not part of the walls. After that, they move on to internal finishing works and, if necessary. We will talk in detail about roof insulation in the following articles.
It is worth noting that building a gable roof with your own hands is not so difficult, the main thing is to correctly calculate and follow the instructions step by step so as not to miss important points during installation.
A short video instruction on the construction of a gable roof is presented in the video:
At the heart of each roof is a large number of beams, rafters, uprights and purlins, which are collectively referred to as the rafter system. Over the centuries-old history of species and methods of its organization, a lot has accumulated, and each has its own characteristics in the construction of nodes and cuts. We'll talk in more detail about what the rafter system of a gable roof can be and how the rafters and other elements of the system should be attached.
In section, the gable roof is a triangle. It consists of two rectangular inclined planes. These two planes are connected at the highest point into a single system by a ridge bar (run).
Now about the components of the system and their purpose:
Filly may still be present in the system. These are boards that lengthen the rafter legs to form an overhang. The fact is that to protect the walls and foundations of the house from precipitation, it is desirable that the roof ends as far as possible from the walls. To do this, you can take long rafter legs. But the standard length of lumber of 6 meters is often not enough for this. Ordering a non-standard is very expensive. Therefore, the rafters are simply grown, and the boards with which they do it are called "filly".
There are quite a few constructions of truss systems. First of all, they are divided into two groups - with layered and hanging rafters.
These are systems in which the rafter legs rest only on the outer walls without intermediate supports (load-bearing walls). For gable roofs, the maximum span is 9 meters. When installing a vertical support and a system of struts, it can be increased up to 14 meters.
Hanging type of rafter system gable roof good because in most cases there is no need to install a Mauerlat, and this makes the installation of rafter legs easier: you do not need to make cuts, it is enough to mow the boards. A lining is used to connect the walls and rafters - wide board, which is attached to studs, nails, bolts, crossbars. With such a structure most of bursting loads are compensated, the impact on the walls is directed vertically downward.
Types of rafter systems with hanging rafters for different spans between load-bearing walls
There is a cheap version of the rafter system when it is a triangle (photo below). Such a structure is possible if the distance between the outer walls is no more than 6 meters. For such a rafter system, you can not do the calculation by the angle of inclination: the ridge must be raised above the puff to a height of at least 1/6 of the span length.
But with this construction, the rafters experience significant bending loads. To compensate for them, either rafters of a larger section are taken or the cut of the ridge part is made so as to partially neutralize them. To give greater rigidity in the upper part, wooden or metal strips are nailed on both sides, which securely fasten the top of the triangle (also see not the picture).
The photo also shows how to extend the rafter legs to create a roof overhang. A cut is made, which should go beyond the line drawn up from the inner wall. This is necessary in order to displace the notch and reduce the likelihood of the rafter breaking.
The ridge knot and the fastening of the rafter legs to the underlay board when simple version systems
The option with the installation of the crossbar is used for. In this case, it is the basis for filing the ceiling of the room below. For reliable operation of this type of system, the crossbar cut must be non-hinged (rigid). The best way- semi-oily (see the figure below). Otherwise, the roof will become unstable to loads.
Please note that a Mauerlat is present in this scheme, and the rafter legs should extend beyond the walls to increase the stability of the structure. To fix them and dock with the Mauerlat, a cut is made in the form of a triangle. In this case, with an uneven load on the slopes, the roof will be more stable.
With such a scheme, almost all the load falls on the rafters, therefore they must be taken of a larger section. Sometimes the raised tie is reinforced with a suspension bracket. This is to prevent it from bending if it supports the ceiling sheathing materials. If the tightening is short, it can be secured in the center on both sides with boards nailed to the nails. With a significant load and length, there may be several such belayings. In this case, too, planks and nails are enough.
With a significant distance between the two outer walls, a headstock and struts are installed. This design has high rigidity, since the loads are compensated.
With such a long span (up to 14 meters), it is difficult and expensive to make an integral tightening, therefore it is made of two beams. It is connected with a straight or oblique cut (figure below).
For a secure fit, the joint is reinforced with a bolted steel plate. Its dimensions should be larger than the dimensions of the cut - the extreme bolts are screwed into solid wood at a distance of at least 5 cm from the edge of the cut.
In order for the circuit to work properly, it is necessary to make the braces correctly. They transmit and distribute part of the load from the rafter legs to the tightening and ensure the rigidity of the structure. Metal pads are used to reinforce the connections.
When assembling a gable roof with hanging rafters, the section of lumber is always larger than in systems with layered rafters: there are fewer load transfer points, therefore, each element has a large load.
In gable roofs with layered rafters, their ends rest on the walls, and in the middle part they rest on load-bearing walls or columns. Some schemes burst the walls, some don't. In any case, the presence of a Mauerlat is required.
Houses made of logs or beams do not respond well to spacer loads. For them, they are critical: the wall can fall apart. For wooden houses the rafter system of a gable roof must be non-thrust. Let's talk about the types of such systems in more detail.
The simplest spreader-free diagram of the rafter system is shown in the photo below. In it, the rafter leg rests on the Mauerlat. In this version, it works in bending without bursting the wall.
Pay attention to the options for attaching the rafter legs to the Mauerlat. In the first, the support area is usually beveled, while its length is no more than the cross-section of the beam. The depth of the cut is no more than 0.25 of its height.
The top of the rafter legs is laid on the ridge beam, without fastening it to the opposite rafter. It turns out in structure two pitched roofs, which in the upper part are adjacent (but not connected) with one another.
It is much easier to assemble the version with rafter legs fastened in the ridge part. They almost never give space to the walls.
For this scheme to work, the rafter legs at the bottom are attached using a movable joint. To secure the rafter leg to the Mauerlat, one nail is hammered from above or a flexible steel plate is placed from below. See the photo for the options for attaching the rafter legs to the ridge girder.
If the roofing material is planned to be used heavy, it is necessary to increase the bearing capacity. This is achieved by increasing the cross-section of the elements of the rafter system and strengthening the ridge assembly. It is shown in the photo below.
Reinforcement of the ridge knot for heavy roofing material or with significant snow loads
All of the above gable roof schemes are stable in the presence of uniform loads. But in practice, this practically does not happen. There are two ways to prevent the roof from sliding towards a higher load: by installing a scrum at a height of about 2 meters or with struts.
Installation of scrapes increases the reliability of the structure. In order for it to work normally, in the places where it intersects with the drains, you need to fasten it to them with nails. The cross-section of the timber for the fight is used the same as for the rafters.
Attached to the rafter legs with bots or nails. Can be installed on one or two sides. See the figure below for attaching the scrum to the rafters and ridge girder.
In order for the system to be rigid and not "crawl" even under emergency loads, it is sufficient in this version to provide a rigid fastening of the ridge bar. In the absence of the possibility of its displacement horizontally, the roof will withstand even significant loads.
In these options, for greater rigidity, rafter legs are added, which are also called struts. They are installed at an angle of 45 ° to the horizon. Their installation allows you to increase the length of the span (up to 14 meters) or reduce the cross-section of the beams (rafters).
The brace is simply placed at the required angle to the beams and nailed from the sides and bottom. An important requirement: the brace must be cut accurately and fit tightly to the uprights and rafter leg, excluding the possibility of its deflection.
Systems with rafter legs. Above the spacer system, from the bottom - non-spacer. The nodes of the correct felling for each are located next to each other. Below - possible schemes for attaching the strut
But not all houses have the middle load-bearing wall in the middle. In this case, it is possible to install struts with an angle of inclination relative to the horizon of 45-53 °.
Strut systems are necessary if significant uneven shrinkage of the foundation or walls is possible. Walls can sit in different ways on wooden houses, and foundations - on layered or heaving soils. In all these cases, consider the device of this type of rafter system.
If the house has two load-bearing walls, install two truss beams, which are located above each of the walls. Benches are laid on the intermediate bearing walls, the load from the rafter beams is transferred to the benches through the racks.
In these systems, the ridge girder is not installed: it provides thrust forces. The rafters in the upper part are connected to one another (cut and docked without gaps), the joints are reinforced with steel or wooden lining, which are nailed.
In the upper non-thrust system, the tightening force is neutralized by the tightening. Please note that the tightening is placed under the purlin. Then it works efficiently (top diagram in the figure). Stability can be provided by uprights, or jointing - beams installed obliquely. In the spacer system (in the picture it is at the bottom), the cross member is the crossbar. It is installed over the purlin.
There is a variant of the system with racks, but without the rafter beams. Then a stand is nailed to each rafter leg, which rests on the intermediate load-bearing wall with the second end.
Fastening the rack and tightening in the rafter system without a rafter girder
For fastening the uprights, 150 mm nails and 12 mm bolts are used. Dimensions and distances in the figure are in millimeters.
The gable roof is used for various wooden houses. You can even assemble the structure with your own hands, since it is simple, in contrast to the four-slope or attic. The main building materials for installation are boards and beams from a bar or log. After reading the article to the end, readers will find out what are the main elements of a gable roof frame, and how to assemble it with their own hands and calculate the cross-section and length of the beams. About.
The rafter system of a gable roof for the construction of a house from a bar consists of: rafter legs, mauerlat, filly, ridge, struts, racks and crate. In order to assemble with your own hands, you need to represent the structure completely. We'll talk more about each element below.
Mauerlat is the main load-bearing part of the gable roof frame structure. It consists of a bar located around the entire perimeter of the house, on load-bearing walls. For the construction of a house from glued laminated timber or other type of lumber, it is fastened using a binding and metal brackets.
Through the Mauerlat, the load from the entire rafter system is transferred to the load-bearing walls of the house. Mauerlat size for wooden house suitable for 100x100 mm or 150x150 mm. Conifers are used for this node. Before laying, the timber is treated with an antiseptic and waterproofed with a bitumen tape.
The main contour of the future roof is assembled from the rafter legs. For the roof frame of a wooden house, a material with a section of 50x150 or 100x150 mm is used. The rafter legs are laid in the shape of a triangle. The entire system is supported on the rafter legs, and it depends on the quality of the material whether the roof can withstand wind and snow loads.
The weight of the entire roof structure is transmitted through the legs to the Mauerlat. Rafter legs are mounted with a step of 60-120 cm, depending on the severity and fastening of the future roof. The heavier it is, the more often the step of mounting the legs of the rafter system.
The ridge is the connecting beam of the two rafter parts of the ramp in the upper part. It is mounted strictly horizontally at the junction of the legs.
For a wooden gable roof, a beam with a section of 100x100 mm is used as a ridge. It is pretreated with an antiseptic.
A filly is an element that acts as a roof overhang. This part is attached to the rafter leg if its length is not enough to form an overhang of at least 200 mm. If the rafter leg is enough, then you can not mount the filly.
For installation, boards of a smaller size and section are used than the legs. The filly makes the installation of the frame easier, since the leg beams are no longer needed in long lengths. If the roof is assembled with your own hands, then experts recommend choosing just this option.
This is a beam that is placed horizontally on the internal load-bearing walls of a log house. The main load from the racks of the rafter system falls on the bed, and he transfers it to the bearing wall.
The installation uses material with a cross section of 100x100-150x150 mm.
The drains are mounted vertically from the ridge to the inner load-bearing wall. For their manufacture, a material with a section of 100x100-150x150 mm is used after calculations. In the rafter system, they play the role of redistributing the load from the ridge to the load-bearing wall. 
The puffs connected to the legs of the frame are in the shape of a triangle. It is the fastener to the system. It is thanks to the puffs that the legs do not scatter in different directions under the pressure of the structure and the roof.
The braces are made up of pieces of planks mounted at an angle. With the help of struts, the load from the rafter legs is redistributed to the load-bearing walls. In connection with the braces, the struts form the trusses. The truss consists of several struts and one tie. Use trusses to transfer the load if the spans are too long.
Roof lathing device
They make a crate from boards or not thick bars. In the rafter system, the lathing is attached perpendicular to the legs to them. With the help of the crate, the load from roof structure(roofing, insulation, vapor barrier -), evenly distributed over all rafter legs. Another function of the lathing is to connect the rafter legs together into a single system. Even a non-edged board is suitable as a crate. But first you need to peel off the bark from it.
If the roof is rolled, for example, bituminous, then instead of boards, sheets of plywood are used as sheathing. This makes the underlay for the roof rigid and flat surface, on which it is easy to roll out the same roofing material.
All of the listed parts of the frame of the gable structure are dried and treated with antiseptic impregnations before installation, you can do it yourself. Otherwise, the rafter system will quickly rot.
The gable roof rafter contract for the construction of a house from profiled timber can be sent or suspended.
This system has a structure resting on the side load-bearing walls of the log house. But at the same time, the rafters interact negatively with the walls, bursting them. To avoid this, in the frame of the gable roof, the legs are pulled together with special puffs. The cuffs and legs form a triangular mount that has stiff ribs and the structure does not deform over time.
In the rafter structure, the role of puffs can be played by floor beams. So the structure can be used as an attic. For greater strength, a tightening of at least 50 cm from the roof ridge is also installed on top of the rafter.
It is necessary to make such a structure if the span between the load-bearing walls of the log house is not more than 10 cm.If this span is larger and there is a load-bearing wall between it, which divides it in half, then the hanging system can be mounted
The slanting rafter system is installed on a log house with any span. Its peculiarity is in the support beam, which is located in the middle in the span of the walls. It is advisable to use such a structure when the distance between the load-bearing walls is more than 10 m.
If there is a supporting column between the main load-bearing walls, then the attic version of the layered rafters can be used. In this case, the rafters will be attached to the column, and additional rafters are made between the columns. But doing it without certain skills is difficult.
Before you start making a roof frame with your own hands, you need to calculate the length and thickness of the beams.
The cross-section of the rafter beams is directly related to their length and fastening pitch. To determine the ratio of these indicators, there are special calculators with which it is not difficult to calculate and GOST.
Calculation of the ratio of the length and section of beams in the form of a table:
| Rafter beam length, m | Section of the material used, mm | Rafter leg step, m | |
|---|---|---|---|
| Beam or board | Log | ||
| 1-3 | 80x100, 90x100, 90x160 | 100, 150, 160 | 1 – 1,35 |
| 3-4 | 80x160, 80x180, 90x180 | 160, 180 | 1,40 – 1,70 |
| From 4-5 | 80x200, 100x200 | 200 | 1,40 – 1,75 |
| From 5-5.8 | 100x200 | 200 | 1,10 – 1,40 |
| From 5.9-6.5 | 120x220 | 240 | 1,10 – 1,40 |
Judging by the numbers, if the length of the rafters is large, then the distance between them decreases, and the section increases. If you take rafters of a smaller section and do not make the necessary calculation, then over the years the roof will sag.
Saw off the beams-legs after the calculation is made, you need the same length and mount each pair on this straight line.
The main stages of building a roof frame with your own hands consist of:
How professionals do roof installation can be seen in the provided video:
In the video, you can see the finished frame from a bar and its description, each node is clearly visible. Readers will find the Mauerlat, rafter legs, their mountings, etc. on the video.
In wooden houses, you do not need to install an additional Mauerlat. Its role will be played by the upper log or timber. But if the roof structure should be higher, then you need to bind the timber.
The laying of the timber begins with its insulation; for this, the walls are covered from above with a double layer of roofing material. The timber is processed and laid. In the corners, they connect it with their own hands using metal brackets and half-section cuttings.
Mauerlat is placed strictly parallel to the opposite wall so that the rafter legs are subsequently the same.
More details on how to attach the rafters to the Mauerlat can be seen in the video below:
The video clearly shows how the fastening of legs - beams to a bar from professionals should look like.
For the exact location of the rafter legs, a pencil and meter mark are made on the Mauerlat. But before that, it is necessary to draw up a diagram or a calculation of their location.
The preparation of the rafter legs begins with a cut from the bottom side, a cut is made 1/3 wide. Their leg will rest on the Mauerlat. The option of their fastening depends on what material the rafters will be.
The slope of the future roof will depend on the angle at which the beams are fixed. You need to make it not very flat and steep. It is better to make a calculation before that according to the indicators of the region. If there are large wind loads on the territory of residence, then the angle cannot be more than 20 ° С. At high precipitation rates, the slope is made at 35-40 ° С. So snow and precipitation will not accumulate, and the roof will self-clean.
In the upper part, the rafter legs are connected to the ridge using iron brackets into a single structure.
Beams - legs are assembled together even before their installation. The connecting elements can be bolts or nuts with iron plates. After the end of the collection of triangular fasteners with rafter legs, they begin to install from the two extreme ones. Then two subsequent ones are installed. You need to fix the frame with temporary jibs. At the end of the installation, they are removed.
After complete installation of the legs, filly are attached to them. The size of the overhang of the future roof will depend on their length. For a wooden house, this distance is taken as maximum in order to prevent water from entering the walls.
With this installation, the rafters begin to be mounted from the bed, on which two supports are installed. A ridge bar is mounted on top of the supports. Jibs give additional rigidity to the structure.
Rafter legs are attached to the ridge beam. If, at the same time, take the length of the rafter legs a little more and file them with a circular saw after twisting, then the work will be more productive.
After the installation of the rafter legs is completed, they begin to fasten the crate. At the same time, spotting begins from the ridge, where first two massive wide boards are mounted.
It is necessary to mount the lathing along the entire length of the gable roof with a step under a certain roof.
When the rafter system is fully assembled, the overhang and gables of the roof are sewn up. After that, the roofing material is laid and the structure is insulated. We talked about how to properly insulate the roof HERE.
As you can see from the article, it is not difficult to do the work with your own hands, but by imagining what the structure of a gable roof looks like, you can easily make a plan and calculation for your log house. And the material that will be used for installation, it is advisable to choose the best and highest quality.
The gable roof rafter system is considered one of the simplest in purely constructive terms. It contains only a few elements, the number of which decreases or increases due to the size of the roof itself. But despite the apparent simplicity, the process of erecting a gable roof itself requires knowledge of some nuances that affect the quality of the final result.
Gable roof rafter system
From the name it becomes clear that the roof structure is two slopes that have a rectangular shape in the plane. More often the slopes have the same dimensions, but there are so-called asymmetric structures in which the slopes differ in size from each other.
In this case, the slopes are set to each other at a certain angle, which is called an inclination. The line of contact is the ridge beam, which is part of the rafter system. In a simple way, it is called a ridge, and it is the highest point of the roof.
The side planes formed by the slopes are called gables. They have triangular shape... After the construction of the roof, the sidewalls are revetted with sheet or panel materials: plywood, OSB, even boards, etc.
The basis of the constructions of the slopes are rafter legs, they are also rafters. They are made either from lumber (beams, boards), or from a steel profile (corner, channel). In private housing, wood is used. It is easier to work with, plus lumber is cheaper.
The device of the gable roof rafter system is not only rafters. In addition to them, there are several more required elements... In the photo below, all the elements of the gable roof are shown. Let's designate them.
Each of the elements of the roof has its own purpose.
Elements of the gable roof truss system
Mauerlat... In fact, this is a beam on which the rafters rest. Its purpose is to evenly distribute the loads from the rafter legs on the walls of the house. If the Mauerlat is not used, then the rafters will press on the walls pointwise, that is, large stresses will arise at the installation sites, which will lead to cracking of the walls.
Rafters installed at an angle.
Ridge, he is a ridge bar or girder. Its task is to form the junction of the rafter legs. A ridge bar is an optional element of a gable roof. There are designs in which it is not installed. But more on that below.
Puffs... They are not always used, but only on hanging rafters or, if the rafter system is installed on a wide house.
Floor beams that form the ceiling in the room and the floor in the attic.
One of the floor beams, which is called lie... It additionally acts as a base for the support posts that support the rafters. Not always used.
Support posts, they are also the grandmas supporting the rafter legs. They are installed only if the length of the span of the house is at least 6 m.
Braces, they are also diagonal props. They are used only if the support posts cannot provide the overall reliability of the rafter system.
There is one more element that is clearly visible in the photo below. These are the support legs for the ridge run. They are installed if the structure of the rafter system is heavy. That is, the entire structure is assembled under heavy roofing material, for example, under ceramic tiles.
Rafter rafters with support legs under the ridge girder
You may be interested in this! Warm roof Is an important detail when building an energy efficient home. From the article at the following link you can find out.
The roof rafter system (gable) can be assembled from layered or hanging rafters.
They got their name because they rest on the lower ends of the walls of the house, the upper ends on the ridge girder. In this case, the rafter elements are subjected to loads that bend them. The construction is reliable, durable, with a high load-bearing capacity.
The photo above just shows the layered rafter system. It is clearly seen that the legs rest in the upper part on the ridge. In this case, there are two types of fastening of the rafters themselves in the upper part:
fastening is made to the ridge:
fastening is made to each other with an emphasis on the ridge (photo above).
It is necessary to immediately indicate that given view The rafter system can be used if the distance between the walls of the house does not exceed 12 m. Because the rafters rest against the lower ends of the walls, and the upper ends only between themselves (there is no ridge run in the structure). Hence the low bearing capacity with a large expansion.
Hanging roof rafters have one purely constructive drawback - a large supporting load on the walls of the house. To reduce it, tightens are installed between the legs to make a hard triangle. Often, the functions of the puffs are performed by load-bearing floor beams.
If necessary, strengthen the hanging rafters, install racks and struts under them.
Hanging gable roof rafters
Two types of rafter system determine two types of technology for their assembly. Let's consider each separately.
There is a certain sequence for assembling layered rafters.
Two extreme support posts are installed under the ridge beam. They will not only support the timber, but also be the elements that form the gables of the building. Attach them at the bottom to the Mauerlat. In this case, they are strictly set vertically, and the upper ends are in the same horizontal plane. To do this, a strong thread is pulled between the racks, the level is checked for horizontalness. If there are deviations, then one of the supports (low) is raised using wooden supports.
Along a horizontally stretched thread, intermediate support posts are mounted with a step of 2-2.5 m. To prevent the beams of the posts from moving, they are propped up with temporary fasteners: props or puffs.
A ridge bar is laid on the racks, which is attached to them.
Produced in pairs installation of gable roof rafters... Installation can be started from either side. Fastening is immediately carried out to the Mauerlat and to the ridge. The main thing is to maintain the distance between the legs, which is determined depending on the severity and bearing capacity of the roofing material. Usually, this parameter is indicated in a house project.
If necessary, intermediate support posts and struts are mounted.
Installing rafters on a ridge along a stretched thread
The technology for installing hanging rafters is different. For this, the entire structure, assembled from two rafters and tightening, is assembled on the ground. That is, roof trusses are prepared in the required quantity, which are then raised to the roof. Sometimes craftsmen assemble roof trusses. Collected one - installed, collect the next.
It should be noted that such farms have a significant mass. It is difficult and dangerous to lift them manually, therefore they use the services of a crane. And this increases the cost of the structure.
Suspended trusses assembled on the ground
The hardest part is setting up the farms. All of them are installed at the installation site with a planned step, where they are temporarily fixed with jibs and props. Then a thread is pulled between the extreme trusses. It must be positioned so that, firstly, it is stretched strictly along the horizon, and secondly, according to the structure, which is higher than the rest.
It only remains to lift roof structures which turned out to be below the stretched level. And the last is the installation of the lathing, which will fix all the trusses into one rafter system. Please note that at the bottom of the rafters will be fixed to the Mauerlat.
You may be interested in this! When the installation of the rafter system is completed, then the turn comes roofing works... From the article at the following link you can find out.
the length of the rafter legs;
step of their installation;
section of the used lumber.
With the length, everything is simple, for this you have to use the Pythagorean theorem, which is based on the formula: c 2 = a 2 + b 2, where c is the hypotenuse of the triangle (these are the rafters), a and b are the legs. The latter are the height of the roof and half the width of the house. All parameters can be easily measured.
The length of the rafters is l 2 + H 2
It is more difficult with the installation step, because much will depend on the mass of the roofing material and the loads from natural precipitation. The larger both loads, the smaller the installation step. But, as practice shows, this parameter varies from 60 cm to 2 m. The latter indicator is used if corrugated board with large corrugation parameters is used as a roofing material, for example, H75.
As for the cross-section of the rafter legs, here, as in the case of the installation step, loads are taken into account, as well as the length of the legs and the step of their installation. Here the dependence is as follows: the greater the load, step and length, the larger the section.
In the video, the process of installing the rafter system:
And one moment. Rafters for a gable roof are laid at a certain angle (marked with the letter "a" in the photo). The slope is selected taking into account the choice of roofing material. That is, some coatings cannot be laid on roofs if the angle of inclination is less than required. Here are some ratios:
the minimum angle of inclination of the rafter system for slate is 22 °;
for corrugated board - 12 °;
for metal tiles - 14 °;
soft tiles- 15 °.
The ratio of the slope of the roof to the type of roofing material
On our website you can find contacts construction companies, which offer a turnkey roof design and repair service. You can communicate directly with representatives by visiting the Low-Rise Country exhibition of houses.
Gable roofs are traditional designs. But from the article it becomes clear that there are two rafter systems that form the basis for the construction of roofs. The one that fits the size of the house is chosen. As a selection criterion, the loads that press on them are also taken into account. Therefore, it is important to correctly correlate everything, taking into account the nuances of construction processes.
The gable roof is the most common construction used in construction. residential buildings, since building a gable roof with your own hands is quite simple and quick. The massive use of this type of roof is explained by its reliable, proven excellent characteristics: it copes well with protecting the house from wind and precipitation, in winter it can easily withstand a significant load from snow, and no special construction skills are required during its construction. It is widely used not only in the construction of a residential building, but also for outbuildings: a bathhouse, a garage, a cellar, a gazebo.
First, let's try to figure out why a gable roof is so popular today, what are its advantages, for example, in front of a hipped roof and which one suits it best.
First you need to decide on the size of the roof and the angle of its inclination. To do this, you need to take into account: the amount of precipitation, snow and wind load in your region, as well as the type of roofing material that will be used.
On a note! The smaller the angle of inclination of the roof, the better design will withstand these loads. However, too small an angle of inclination will not allow in full use the attic space, so you need to find a middle ground.
Before you start building a roof, you need to familiarize yourself with what it is and what it consists of. In accordance with the project of the house plan, the future structure and shape of the roof is being developed.
A gable roof consists of two inclined planes (slopes), located at an angle to each other, connected in the area of the ridge. Triangular pediments are formed at the ends of the roof.
Mauerlat as it is often called (roof foundation) - a support bar for rafters installed on the top of the walls of the house, evenly distributing the load on the building. In a house made of wood, the last row of the log house acts as a mauerlat.
Installation of the Mauerlat on brick or block walls is carried out using powerful anchors. Mauerlat is made of dried wood, treated with a protective fire-fighting and antifungal agent, with a cross-section of 100x100mm. up to 150x150 mm.
Rafter legs- installed in pairs, on both sides of the roof and fixed on the ridge, thereby forming the rafter system (roof contour).
The pitch of their installation is usually in the range of 0.6-1.2 m, and depends on the type of roofing material used. The heavier the roof is, the smaller the pitch is used. Rafters are made from dry edged boards conifers, from 50 mm thick. For the safety and durability of the structure, it is also necessary to use special impregnations for wood.
Roof ridge- horizontal, upper line of connection of the rafter legs to each other. Its height at the beginning and at the end in relation to the upper points of the walls should not differ. You can measure this using the hydro level.
Do-it-yourself gable roof - elements of the rafter system
Hanging rafters at the top rest on each other, and at the bottom to the tightening or floor beams. In houses built of wood, the fastening of the rafters to the Mauerlat is made sliding, this will avoid breaking the roof frame when the house shrinks.
Roof truss Is a flat structure, which includes: rafters, posts, braces and guy wires. the main task this design, arrange all the elements so that the inner walls of the house do not experience stress, and the entire vertical load goes to the outer, strong walls. The wider the span, the more struts and braces will be required.
Do-it-yourself gable roof - gable roof truss
Suitable for the type of roofs, the span of which is from 10 to 16 m. The rafters can be installed at any angle, and the presence of load-bearing walls or columns is required in the house. At the top, the rafters rest on a ridge girder supported by an inner wall or uprights, and at the bottom on a Mauerlat.
The loads in this design are vertical, so there is no need to install puffs. To strengthen the rafter legs, are installed crossbars and struts.
On the walls of the house along the entire perimeter, as well as on the inside, the Mauerlat and the bed are attached to the anchor bolts, additionally fastening it on the inside with a strong metal plate.
A waterproofing material must be placed under the Mauerlat; roofing material is most often used. The material of the Mauerlat and the bed is a bar with a cross section of 100 to 150 mm.
Do-it-yourself gable roof - Mauerlat mount
On the Mauerlat and the bed, opposite the rafter legs, floor beams are placed. They are made from edged boards 50x150 mm. For further safe movement, you can put a rough floor on them, securing it with a self-tapping screw or a nail.
Under the ridge girder, racks are placed on the bed, fastening them to the bed with powerful metal corners, plates or nails, the installation step is not more than 2 meters. Racks (supports), using a level, are aligned vertically, and temporarily fixed in any suitable way. Then a girder (ridge bar) is placed on the vertically installed supports and fastened in a similar way.
Do-it-yourself gable roof - installing vertical racks under the ridge
Rafter legs are made from edged boards. First, a template of one leg is made, where the angle of the saw cut of the attachment to the ridge bar and the Mauerlat is measured. The resulting template must be measured on both sides of the roof at the rafter attachment points.
If the cut is done correctly, then the rest of the rafters are made according to the template. In the event that the Mauerlat and the ridge bar are installed strictly horizontally, the fitting of the template in all places can be omitted.
do-it-yourself gable roof - fastening diagram of the main nodes
If the board has a sufficient length, then the overhang from the roof is left at least 30 cm, otherwise it will be necessary to lengthen the rafters by attaching an additional board (filly) to it.
In the ridge, the rafters are fastened to each other using metal plates and nails. In attaching the rafters to the Mauerlat, metal brackets are used, one end of which is driven into the board, the second is driven into the Mauerlat, in addition, you can use corners and nails.
If the width of the roof is large, the rafters are reinforced with struts, which are attached at an angle to the support post standing on the bed and the rafter itself. After all the rafters are installed, their length is measured again and if there is no need to adjust it, then a wind bar is nailed to the ends of the board.
Important! The rafters of the layered type withstand greater loads than a system with hanging rafters, therefore this design is chosen when building large houses with the presence of an attic floor and an insulated roof.
Such a rafter system is ideal for the construction of gable roofs, where the span does not exceed 6 meters, and there are also no internal load-bearing walls. The support of the lower parts of the rafters is the Mauerlat, at the top, resting on each other, they themselves are supports.
A feature of this design is the need to use a tightening that does not allow the rafter legs to diverge, thereby, there is no expanding load on the walls of the house and only a vertical force acts. An additional bolt (crossbar) can also be installed under the ridge. Everything construction works are made by analogy with the installation system of layered rafters.
Do-it-yourself gable roof - examples of hanging rafter systems (diagram)
The advantages of the hanging system include the absence of support posts in the center, which makes attic floor more spacious and allows you to more rationally plan this space.
This design is lighter in execution, it requires less building material, which automatically significantly reduces its cost. It is recommended for use in the construction of small houses. The reliability of this design is high enough.
As you can see for yourself, a gable roof with your own hands is a completely doable task for everyone. You just need to have basic knowledge and building skills in order to do everything right.
