Roof rafters with own hands. Drawing and construction of rafters

A gable roof system is considered a fairly inexpensive option for a roofing device. It is often chosen by the owners of private residential buildings. This is a simple and practical rafter system. Its design is reliable and provides the necessary protection from the weather. Next, let us consider in more detail the possible variants of its arrangement.

General information

The gable roof system is a combination of rectangular planes at an angle. On the sides, there are openings of a triangular shape. In them are inserted pediments. The roof structure (rafter system) includes various supporting and retaining elements. They provide reliability and durability. Next, let's look at what the roof structure consists of (a rafter system).

Mauerlat

The element is represented by a bar having a square section. It is made of coniferous species. Mauerlat is designed for uniform transfer of load from the rafter to the bearing walls. The size of the timber, as a rule, is 10-15 cm. It is laid along the bearing walls. As the fastening element protruding rods on the thread or anchors.

"Leg"

It is a bar whose size is 15 X 5 (or 10) cm. With this element, the triangular contour of the roof is assembled. It, in turn, carries all the load from atmospheric phenomena: snow, hail, rain or wind. To ensure greater reliability rafter legs are located at a distance of 0.6-1.2 meters. The distance is less than the depth of the roof. In addition, the size of the step in some cases will affect the structural features of the roof covering.

Sill

This bar has the same cross-section as for the Mauerlat: 10 x 10 cm. It is laid horizontally on the bearing walls. This ensures an even load from the racks.

Tightening and braces

The first element completes the triangle of the "legs". The tightening prevents it from spreading. The struts fulfill the task of the link between the rafter legs and the supporting elements. When you connect these parts with tightening, you get a farm. This element is very strong. Even in the case of a large span, the farm will be able to withstand all loads.

Racks

For these elements, the same bar is used, as for the tightening. The racks are located vertically. They take on the load from the ridge and transmit it to the bearing inner wall.

Rims

Elements of the frame are laid perpendicular to the rafter legs. As part of the crate can act boards or bars. This construction transfers the weight of the roof to the legs of the rafters and provides their additional fastening. It is better to take trimmed elements for the crate. However, if this is not possible, you can use a unedged board or a bar with the bark removed. If a soft roof covering is used, for example, tile based on bitumen, the crate is made solid. In this case, plywood sheets (moisture resistant) act as its elements.

The horse and overhang

The first element is the upper section of the roof. Here, the roof slopes are connected. The horse is formed by connecting the legs. It is located horizontally. At a distance of about 40 cm from the walls is overhang. This element protects against rainwater.

"Mares"

These elements form a overhang. "Mares" are necessary only when the feet of the rafters are too short. For these elements, smaller boards are used.

Roof truss system: types

There are only two of them: a layered and hanging type. The latter are applied in the case when the walls of the exterior walls of the building are located at a distance of up to ten meters from each other. Another condition, which uses a suspended roof truss system (shown in the article) is the absence of a load-bearing partition between the opposite elements of the building. If it is, then a nylon type is used. If the separation within the structure is carried out using columns, rather than a bearing wall, both rafters are used. The drawing will consist of the elements located at an inclination, and the hanging parts located between them. Next, consider the structure in more detail.

Hanging type

A feature of this scheme of the device system is the location of the rafters with support on the side walls. A disadvantage in this case is the formation of a bursting load, due to which the walls may eventually undergo destruction. To prevent this phenomenon, a tightening is used to join the rafter legs. As a result, a rigid triangle is formed, which does not undergo deformation under load. Instead of puffs, overlap beams are often used . They are particularly relevant if an attic space is planned. Such a gable roof system with its own hands settles quite simply. The plus of this structure is the absence of the need for fixing the Mauerlat. Together with this, the elements of the structure, where the rafter legs rest on the walls, are quite simply fastened. The board laid through the insulation layer will make the farm even and stable. This is made possible by providing a larger footprint. There are several types of suspended rafters. They are all three-hinged.

Simple triangular construction

This gable roof system with its own hands is going to be the easiest. The structure is a closed triangle. Its two upper sides are subject to bending stress. The tightening used in this design does not work solely on stretching and does not apply to the carrier element. In this regard, it can be replaced by a steel cable. There are several options for organizing the device eaves. For this, plate or board mounts can be used, as well as frontal orthogonal felling.

Three-hinged triangular arch using raised neck

Such a gable roof system with its own hands is arranged in the event that the equipment of the attic room is expected. In this case, the tightening is not set at the bottom, but at the top. In this case, the tensile load is increased. The rafters themselves are kept on the beams of the Mauerlat. At the same time, the load becomes uniform, because of which the whole rafter system of the gable roof will be more stable. The calculation of the structure should be carried out taking into account that the edges of the elements should protrude beyond the outer walls of the building. To prevent sagging, tighten it with a suspension. This is especially important when it is planned to build a suspended ceiling or laying an insulating layer. In case the tightening is short, it is fixed to the ridge and the crossbar. For this, two boards are nailed. If the tightening is long, then several suspensions are made.

Layer type

If such a rafter system of a gable roof is arranged by one's own hands, then it is necessary to arrange a vertical beam exactly in the middle. The weight of the roof will pass through it from the ridge to the inner supporting wall located at the same distance from the edges of the building.

The undisputed built-up structure

It is possible to mount such a gable roof system with its own hands in three ways. The first option involves the presence of Mauerlate as a support. Or the rafters are hemmed with a special beam. For fixing, tooth-cutting is used. To ensure reliability, the structure is insured with wire or clamps. At the top of the elements, holes are necessarily fixed. According to the second variant, the roof rafter system is equipped with the help of a sliding joint by the type of the slider. It is also possible to fasten with a piece bar. In order to ensure a strong hold on the leg, a nail is driven from above or a flexible steel plate is fixed. The rafters lying on the ridge run are fastened in pairs to the holes or to the run. As for the last version of the installation, there is a rigid connection. Parallel to the ridge element, bridges or planks are packed from either side. In this case, a strong bending stress is applied to the beam. However, the truss legs are much less bent. This type of installation is somewhat more difficult to perform than the first one. In this regard, it is used less often.

Spacer layer elements

Such a roofing device is almost similar to the above options. However, in this case there is a nuance: the movable attachment of the legs must be replaced by a fixed (rigid) one. In this case, the expanding load of the rafters will be transferred to the bearing walls. In general, such spacer elements act as an intermediate link from an inclined to a suspension system. However, you can do without a run. To equip the spacer system, a very strong fixation of the Mauerlatt to the wall of the house is necessary. In this case, the building elements themselves must be strong and thick.

Rafters with struts

In this case, the additional elements are set at an angle of 45 degrees. The hinge, in fact, acts as the third leg of the rafters, which works on compression. Thus, it becomes possible to block spans that are up to 14 m in length. Beams with a small cross-section can be used. Calculation of the attachment of the strut is not necessary, since it is sufficient to substitute it under the rafters and nail it from the sides. In this case, the element will not move. However, the main thing is the exact cutting of the angle of the strut. At the same time, the slope of the rafter should be taken into account. To determine the cross-section of the bar, it is necessary to determine the compression load.

Sub-truss constructions

They are used in buildings with two bearing walls. Podstropilnye designs include beams, laid along the long side of the roof. Under them are installed racks, which are laid beams. As the support also serve the inner walls of the building and the log. The rafters in the upper parts are connected one to the other. They are bandaged with wooden or steel plates. Ridge run is absent, in connection with which there appears a spacer. The tightening is placed below the through runs. In this way, the spacer is eliminated. For the stability of the pillars at the bottom, fights are fixed. They take the load on the compression, acting as a bolt. The fastening of the stitches is done crosswise.