Single-pitched roofs are built on various structures. It does not have to be a barn, a garage, a sauna or a utility room. Such roofs are used in complex roofing structures of cottages. The single-rafter system is somewhat simpler in design than the gable, and accordingly, it requires less costs and materials. The roof rafter system is built with soft roll materials or sheet-shaped hard roofing.
Contents of
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- roof saddle roofing system
- roof slope system for sloping rafter systems
- roof saddle roofing system
- rafters construction tools
- single-rafter truss system tools and materials
- self-sloping truss system installation
- installation of a single-roof truss system. Video:
Single-roof roof system for roof
The slope of the roofing system for a single-pit roof is chosen depending on the roofing material used. The minimum angle of inclination of 5-10 ° is allowed when using roll materials such as ruberoid or rubimaster. For the construction of roofing from wave slate, the rafter system of a saddle roof is made not less than 20 °, and for a roof tile the permissible slope is 25-35 °.
Scheme of a slope of a rafter system depending on the roofing material
When calculating the power of the skeleton of the rafter system, the following is taken into account:
- design weight of the roofing material, waterproofing and insulation;
- weight of the truss system itself;
- wind and snow loads averaged for the region;
- safety factor up to 50% in case of natural disasters.
Constructive elements of the
saddle rafter system. For the construction of a single-pitched roof rafter system, lumber of coniferous or hardwoods resistant to parasites and rotting is required. The permissible moisture content of wood for the frame of the rafter system is not more than 15 -17%.The overall dimensions of the timber are determined depending on the design loads on the roof, the total roof area and the slope angle.
- Beams with cross-section not less than 150х150 mm are used for mauerlat, lozhja, puffs and бабки.For rafter feet - board 50X150 and more. A bar from a section of 50x50 is used to arrange the struts and rear legs. For the battens, a unedged board of 20 mm in thickness is also suitable, and for a continuous plywood or OSB 10-12 mm.
- Mauerlatom called longitudinal beams, fixed on the top crown of the building. From the lower Mauerlat to the upper Mauerlat are fastened rafters, and to the vertical headstock - the tightening.
- The upper mauerlat or longitudinal ridge beam is installed at the top of the saddle rafter system. The beam can be attached to the highest wall of the building box or adjoined to another wall, depending on the architectural design.
- Rafting - inclined board connecting the upper and lower Mauerlat. The thickness of the board depends on the weight of the roofing material. The rafters are stuffed with a crate.
- Granny is a vertical stand supporting the upper Mauerlat or ridge run. The lower end of the head restrains itself in a tightening.
- Tightening - horizontal joist connecting the headstock with the Mauerlate. As a result, a rafter profile of the rafter frame is obtained from the rafter, the tailstock and the tightening.
- A ladder is a longitudinal beam located in the middle of the attic space parallel to the mauerlat. Its ends are connected with a long beam.
- With a steep slope of the rafter system and the length of the rafters more than 6 meters, additional vertical struts are installed. They are attached between the rafters and the bed. From them, at an angle, the legs are installed.
Rim - unedged board stuffed across the rafter legs. The packing step is calculated according to the overall dimensions of the roofing sheet. For soft roofing materials in rolls, the crate is made of a continuous sheet of waterproof plywood, OSB, and the like.
Tools and materials for mounting the
saddle rafter system. From the tools for erecting the rafters, you will need:
- woodworking: wood hacksaw, carpenter's ax, carpenter's, chisel and chisel;
- measuring instrument: measuring tape, plumb line, building level, woodworking corner;
- drill, hammer, screwdriver.
Assembly and consumables:
- lumber: beams, timber, board;
- fastening materials: nails, screws, staples, studs;
- insulation materials: roofing material, bitumen mastic, antiseptic for wood.
Assembly of a single-girder roofing system with our own hands
Saw-cut and sawn timber sawn timber systems are processed with antiseptic and refractory impregnation for wood. The ends and planes of the beams, attached to the brick wall, are treated with bituminous mastics. Samples and the top crown of the wall in places of contact with the wooden frame of the rafter system are laid by roofing material.
- Mauerlat is installed on the lower longitudinal wall of the building. For its fastening in advance during erection of a box of the house in a last row of a brick metal шпильки are stuck. Diameter of hairpins from 10 - 12 mm and more. A beam of Mauerlat with drilled holes is installed and tightened with nuts with wide washers. During the installation of the rafter system, the nuts are periodically tightened. Wood has the property of slowly contracting, and the resulting backlash is selected until the Mauerlat is firmly secured. Similarly, the upper Mauerlat or the runner's ridge beam is attached. If the Mauerlat is stacked around the perimeter of the box of the house, the corner joints of the beams are made by the method of notching in a half-beam and additional fixation by nails and staples.
- Rafters are fastened with anchors, screws or nails to the beams of the Mauerlat. The pitch of the rafter legs is calculated from the width of the roofing sheet. Two parallel legs of the rafters are located along the central line of overlapping roofing sheets, i.e.step rafters to 15-20 cm already roofing sheet. In the lower part of the roof slope, the filly protrudes 20-25 cm from the wall cut.
- For the installation of struts and podstropilnyh supports, at the ends of the beam and the installation site is sampled in a half-round and nailed. As additional fasteners a metal corner, bolts or roofing brackets are used.
- Depending on the type and weight of the roofing material, a solid or thin crate is made. The spaced lath is packed with nails in steps of 10 cm to half a meter. For it, you can use and unedged board, cleared from the bark. It is important that the board is of equal thickness and evenly distributed along the plane of the rafter system. For a continuous crate, waterproof boards of particleboard, OSB or plywood are used. Mount better with galvanized screws.
