The erection of the roof is one of the most important stages in the construction of the house. The simplest structures include gable roofs with straight ramps. Their calculation and installation can be performed independently, having carefully read the step-by-step instruction. Functional parameters of the roof also depend on the correct insulation, characteristics, and quality of the finish coat installation.
To determine the configuration and size of the roof, it is necessary to take into account the snow and wind load in the existing climatic conditions – the smaller the angle of inclination, the better the construction resists the loads. But a small angle of inclination (40 degrees or less) does not allow full use of the attic space.
The shape and construction of the roof are designed in accordance with the design plan of the house: the key points of support of the roof truss system must coincide with the lines and points of location of the bearing structures of the underlying floor. Thus, it is necessary to take into account the width of the house, the presence of a longitudinal load-bearing wall in the center. If the attic is not planned to be used as an additional useful area for permanent or seasonal living, you can build a reliable roof with layered rafters. In this case, the rafters are attached to the ridge run, which supports the posts resting on the inner supporting wall.
Hanging rafters – the most practical and economical option for light buildings. In this case, the rafter legs are connected in pairs by bolts – horizontal bridges, which provide the necessary rigidity of the structure. The system with hanging rafter’s rests on the side walls of the structure.
If the width of the house exceeds 6 meters, in addition to the crossbars, which serve as the basis for the ceiling, the installation of runs and racks is carried out. The run is a horizontal bar that acts as an additional support for the rafters that form the roof slope. Mounting the run requires the use of racks. Racks, in turn, rely on the ladders – a special bar, laid along the ramp. Lying and stands perform the function of the skeleton of the walls of the attic room. Such a built-in design allows you to make a loft or a spacious attic for your own needs.
If construction of a simple and reliable roof is required, a gable construction with an angle of inclination of 45-50 ° is ideally suited. This rafter system is suitable for installation on residential buildings and buildings for various purposes. When calculating materials, it is necessary to take into account that the rafter system should be light enough to avoid excessive load on the foundation, but at the same time is strong. The sawn timber section should be chosen based on the dimensions of the rafter structure.
Mounting the Mauerlat
Consider a step-by-step way of building a roof with ramps and a loft. At the first stage the installation of the upper strapping – Mauerlat – is installed on the longitudinal walls of the house. The piping takes on the pressure of the entire roofing system and evenly transfers it to the building structures – walls and foundation.
“Mauerlat is made of a bar (section from 50 × 150 to 150 × 150 mm), treated with special protective means to protect from rotting and ignition.”
Mauerlat can be done in various ways:
- in the masonry, rolled wire is embedded, through which the bar is fixed to the wall (the wire is passed through specially made holes and tightly twisted);
- in the masonry long metal studs with a diameter of 12 mm are embedded;
- In the upper part of the wall, a monolithic concrete beam with embedded steel studs is made.
The studs should be located in steps of not more than 120 mm. The height of the protruding end of the fastening element should be 20-30 mm higher than the total thickness of the waterproofing and the bar, in which it is necessary to make holes in advance. The beam is put on the studs and tightened with nuts with wide washers.
Roofing system erection
The roofing system, which can be made with your own hands, consists of a number of elements, united in a single whole. A rafter A-shaped truss is a rigid structure, working “on the strut”. If the construction of the roof is carried out on a timber house, the opposite walls should be reinforced with 100 x 150 mm screeds at the level of the ceiling beams. This is done so that the walls do not move apart under the load.
On the ceiling overlap lie down – additional elements from the bar 150 × 150 mm or more, which serve as a support for the pillars and redistribute the point load on the surface of the overlap. Folding with your own hands should be done along the lines of the location of the walls of the future attic space. If the attic is not planned to be used, the ice can be laid directly under the ridge for mounting the support posts. If necessary, you can do the splicing of the bar, but only in the places where the joint will lie on the beam. The stud joint is strengthened by a bracket or metal plate.
Repeating details of the rafter system should be made completely identical to each other in order to build an isosceles gable roof, the weight of which will be evenly distributed even under atmospheric loads. With this end in mind, we make the patterns of the same parts with our own hands.
On the floor of the house, boards of 50 × 150 mm are laid out, a triangle of the required height is made of two rafter legs and a plank (its length corresponds to the height of the future roof) connected by a nail. With two or three of them, the structure rises – the rack is installed on the central axis of the ceiling, the rafters are mounted on the Mauerlat.
“During the preparation of the template, you can extend the elements, varying the height of the roof and choosing the most suitable option.”
Having defined the dimensions, it is necessary to make curly cuts on the rafters in the places of their contact with the harness. The rafter should be firmly resting on the Mauerlat. There are a number of ways of fastening, it is necessary to choose the most convenient and reliable, it is desirable to use metal overlays. With the subtleties of technology can be found on the video. The resulting rafter structure later acts as a template, and the support board helps to control the height of the installed trusses.
The pediment is a continuation of the wall, bounded by the roof slopes. If a gable roof is provided, the pediments of the house are triangular. When installing the truss structure, the first trusses are first installed, which later serve as a frame for the gables. It is necessary to strictly verify the verticality of the structures and make sure that they have the same height. In the upper part of the pediments, a ridge run is attached, to which the rest of the rafter structures are later mounted.
Typically, the pediments are sewn up after the roofing works, but this can be done at an earlier stage. Mounting of boards 50 × 100 or 50 × 150 mm is carried out in a vertical or horizontal direction. The pediment, which can be built with their own hands, is often provided with windows.
It is necessary to provide for the insulation of the pediments.
Roof insulation and roof installation
The lath is stuffed onto the rafter system, the step of which is calculated based on the characteristics of the roofing material – its dimensions and stiffness, the method of installation. If the use of flexible materials (bitumen shingles, PVC film, rolled bitumen roofs) is required, it is necessary to make a continuous flat floor.
To insulate the roof must be treated as carefully as possible, otherwise, heat losses will be very significant. Usually, gable roof is immediately performed taking into account the use of various materials for insulation – when building a rafter system with their own hands, the rafter step is calculated relative to the width of the sheet insulation. This allows you to build a roof with minimal economic costs, as the material for insulation will not have to be cut. In addition, this approach speeds up and simplifies the installation of a thermal insulation and vapor barrier system.
The construction of a gable roof is recommended to be performed by two assistants. Compliance with the technology of work allows us to build a reliable, durable construction.