Rafter connection

Any construction consists of a set of measures and, perhaps, one of the most important stages is the installation of the roof truss system. It performs the bearing functions for the roof, and the roof in turn protects the rest of the structure from the negative effects of the environment. Therefore, we can say that ensuring the strength and stability of the frame truss system is one of the priorities. A lot depends on how well the connection is made. This is what will be discussed below.

Types of compounds

It should be noted that the main differences between the compounds, as a rule, are due to the place of their localization. And, on this basis, the node connections of the rafters can be divided into several separate groups:

• connecting truss foot with a mauerlat,
• connection of rafter legs among themselves,
• connection of truss legs and ridge beam,
• connection of rafter legs and additional elements of rafter system (struts, braces, puffs),
• connection of components of rafters when joining elements.

Each of these connections can be made in different ways, the implementation of which is somewhat different from the technological side. Different connections will be made using different fasteners. For a better understanding of the subject matter and the nuances of work, each of the methods of connection should be considered separately.

Bond of separate parts

Butt. Butt joints should be considered as one of the main ways of connecting elements of the truss system. With such a connection, the fastened parts abut each other. Basically, this method is used to increase the length of elements, for example, rafter legs. The ends of the component parts that need to be joined are sawn off at an angle of 90 ?, after which they are combined and joined with the help of overlays. You can use as trim wooden boards, and special metal plates.

Note! Attach the lining can be nails or screws, but it must be remembered that they must be placed in a checkerboard pattern.

The method of the cut. The next way to connect parts of the truss system is the so-called oblique hem method. This technique is also used when connecting the components of the truss legs to each other. In this case, the ends of the parts to be joined are sawn at an angle of 45 °, after which they dock with each other. After that, a through hole is drilled into which the threaded rod is inserted, with which the elements are attracted.

Note! When tightening, wide washers should be used to prevent the possibility of cracking.

Innocent. Another option for fastening individual parts in the truss system is overlapping. This method is characterized by the fact that the connected parts overlap with each other with some spade in length and are fixed with screws or nails. Thus, it is common to combine the components of the rafter legs, if their length is not enough. The same method can be applied when assembling long rafters of three components, when one part is clamped between two others and fixed with screws.

Note! If composite truss legs are used, their rigidity must be uniform throughout the length. If this is not ensured, the roof may be deformed.

The connection between rafters

As for the joints of the rafter legs between them at the top, there may also be various options here.

1. Rafters can be overlapped. That is, it is about the fact that the trusses are superimposed on each other, after which the through hole is drilled and the parts are attracted by either a bolt with a nut or a threaded stud. At the same time, wide washers should be planted on both sides.
2. Rafters can be connected at an angle. To do this, the ends are sawn off at the right angle, joined to each other or to the ridge girder and tightened with nails or self-tapping screws. In the absence of a ridge beam, the rafter legs can be connected using a special mounting plate, which is superimposed on both sides. Bolts or threaded rods are inserted into the through holes in the plates and rafters, and the elements are tightened.
3. Another way to connect truss feet in a skate is a half-tree cutting method. In this case, a jigsaw or a hacksaw on both rafter legs cut out notches, down to half the thickness of the beam. After that, the parts are connected, and a through hole is made at the docking point, through which the elements are drawn to each other with a bolt.

The connection of truss legs and mauerlat

Along with other things, it is necessary to consider the ways of connecting the rafter legs and power plate. This connection node plays an important role, because it is thanks to him that the whole truss system is fixed to the rest of the building frame. The connection can be made in several ways.

• Joining with a trim in a truss. In this case, a cut is made in the truss leg, up to a third of the thickness of the truss leg, which plays the role of a kind of groove. The purpose of the cut is to counteract various rafter shifts relative to the power plate. After installing the elements, they are fixed with the help of three nails, two of which are driven in at an angle to the plane of the Mauerlat, and the third is vertically. Thus, the connection is quite strong.
• Also, the rafter leg can be fixed using a specially mounted support beam. It is attached to the power plate, and the rafter leg rests on it. To prevent displacement on the sides of the truss foot fixed metal corners are installed.

As for how the additional elements of the truss system, various struts, bracing, tightening and bracing are connected, it should be said that this can be done in any of the ways listed. It all depends on the case.

It is also worth adding that as a consumable material used in the assembly of the truss system, both usual nails and self-tapping screws, wooden wedges, bolts or threaded rods can be used.

To conclude the above, you can add a few words about the fact that despite the way in which the individual elements of the truss system will be mounted, it is important to remember one rule. Unnecessarily rigid fastening elements is extremely undesirable. The fact is that a tree with temperature and humidity drops tends to change its size to some extent, namely, to expand and contract. This is a natural process.

Note! If all fastenings are made unnecessarily rigid, this can lead to a violation of the integrity of the whole structure.

By the way, some deformations can occur as a result of soil shrinkage, so this rule seems to be quite relevant in most cases.

Video

This video shows how to join and splice rafters: