The roof in any house is the face of the owner, protection from the weather, the safety of its residents. Rafters for the roof are the bearing, the main part of the structure and the main element. The appearance of the house depends on their construction. First you need to figure out what types of coverage exist. Roofs are flat and pitched. The latter are divided into three design options, depending on the number of slopes and the engineering solution:
- single slope;
- gable;
- multi-slope.
In the installation of the roof can be distinguished: tent, hip, half-hip, mansard and other roofs. Rafter systems can be layered and hanging. As a rule, in practice, a combination of several types of rafter structures is used.
Roof construction always starts with design. It is necessary to calculate the strength of external factors. Take into account additional features of the functional use of the roof, taking as its basis its main task - protection and safety at home. A properly planned roof can help to increase the living or economic area of the building. Here you can equip a room for rest and guests, use the space for storing household equipment and blanks. When calculating the following must be considered:
- the strength and speed of the wind in the region of the house under construction;
- the amount of annual precipitation characteristic of the area;
- characteristics of the material (weight, strength, etc.) from which the roof will be made.
Rafters for a shed roof have the simplest design. They are used for outbuildings, summer kitchens, and also in cases where the house has walls of different heights or is located in mountainous areas. The roof covering is turned on the windward side. The rafter system is applied in layered. These are two inclined beams in relation to each other, in the upper part connected by a ridge, and the lower parts resting on two longitudinal beams, which are called "Mauerlat". The angle of inclination is determined individually with the calculation of the necessary parameters and existing conditions.
For low-rise construction, mainly for the construction of cottages, gable types are used - they are the most economical and reliable. The rafters for the roof are used both for outdoor and hanging. To install the first option, you must have internal longitudinal walls and poles. In the absence of them, only the external walls of the house and the hanging rafter system, which provides for the presence of puffs - horizontal beams, which are the support for the rafters, their strengthening and uniform distribution of the load, are used for the construction bond. This provides the necessary stability and fixing the middle of the structure. Depending on the weight of the roofing material and possible precipitation, the roof rafters consist of racks, struts, stops, crossbars. The whole system is called a "truss farm". Its most reliable form is a triangle. The material for manufacture is coniferous wood with preliminary treatment with fire-fighting and antiseptic agents. It is worth warning that if you do not have experience in the construction of this type of structure, then professional roofers should make roof rafters.