How to make a truss system 2

During the construction of the roof of the house the installation of the truss system is considered to be the most crucial and difficult step. Roof maintenance is associated with constant and periodic loads in the form of snow or gusts of wind.

To figure out how to make a truss system with your own hands, you need to decide on its components. The rafter frame is used for any type of roof, it differs by the level of complexity during installation. Shed and gable roofs are considered simple structures. Hip or hip roofs provide a reliable roof, but are difficult to calculate and install rafters.

When choosing the size of the material for the frame has to take into account many factors. The cross section of the rafters and the supporting base must withstand the weight of the roof, climatic loads, the mass of devices installed on the roof (if any will be installed).

Main elements

The following elements are necessary for the gable roof skeleton:

1. Mauerlat is a timber of significant size 150? 150 mm or 200? 200 mm, which is laid and fixed along the perimeter of the walls. It connects the roof system and the structure of the building into a general structure, distributes the load exerted on the walls.
2. The ridge is the highest point of the roof, where the rafter legs are connected. The longitudinal beam helps to keep the structure, provides stability under wind loads.
3. Rafters - are made of boards with a section of 70? 150 mm, they have the entire load. Of the boards are truss legs, which are mounted in increments of not less than 60 cm.
4. Lezhine - the bar which is parallel to the fad. Its dimensions are equal to the power plate. Lent is a support for racks and other elements.
5. Tightening - the crossbar of the boards connecting the rafter foot.
6. Racks - bars, installed vertically, they are installed to support the ridge girder.
7. Overhangs - parts of rafters, protruding beyond the wall. They allow you to divert precipitation from home.
8. The struts - are used to strengthen the rafters, allow you to create durable structures.
9. Crate - boards required for tying rafters and laying roofing material.
10. Filly - when the length of the rafters is not enough for the overhang, fill additional boards "filly".

Varieties of roof systems

For the device frame gable roof uses several types of roof systems.

Sideways - the choice of this design implies the presence of a support in the form of a wall in the center of the building. They get three points of support and are only subjected to bending. The upper part of the truss foot rests on the girder, and the lower part on the power plate. This system allows you to use thinner lumber, reduce costs and carry out a construction of less weight.

Hanging - truss legs rely only on the walls, so they are under heavy load. To give strength connect by tightening. Such rafters are usually collected at the bottom and served directly for installation.

Complex roof forms require non-standard solutions, for which combinations of hanging and wall girders are used.

When installing the four-sided roof, the main framework is the diagonal rafters connecting the ridge girder and the corners of the building. They are supported by ladders - short rafters, which together with ordinary side rafters form the basis of the roof slope.

Material preparation

The service life of the truss construction depends on the quality of the sawn timber and its processing. For structural elements it is necessary to select dry wood, with a moisture level below 22%. It should be smooth and knotless. Before installation, all parts are treated with two layers of antiseptic and means that prevent burning. When processing it is worth using a brush, but not a spray, then the composition is better absorbed. When choosing lumber, coniferous wood is preferred.

Mount

The durability of the structure will ensure proper installation of the truss system with your own hands. To connect the rafters use different types of fastening: brackets, nails, shaped steel parts - angles and platinum, which are fastened with screws.

Cross section

The dimensions of the timber used for the rafters are influenced by:

• span size;
• constant load on the roof;
• impact of climatic conditions;
• the angle of the slope and the pitch of mounting truss legs

Permanent load is calculated from the total weight of the roofing material, insulation and waterproofing. With increasing distance between the rafters, a larger section material is required. The coefficient of wind and snow load necessarily laid in the calculation of the cross section. The common size of rafters is 50? 150 mm and 60? 200 mm.

Rafter length

The base of the symmetrical gable roof is an isosceles triangle. Knowing the height of the ridge, you can calculate the length of the rafter by the Pythagorean theorem. In this case, it is a hypotenuse, and half the width of the lady and the height of the roof are the legs.

Installation of rafters

The first step in installing a truss system for any kind of roof is the installation and mounting of the power plate. Under it must fit waterproofing in the form of roofing material. This timber requires the drilling of holes along the length, into which the studs walled in the masonry are inserted and tightened with a nut.

Having created the basis for the frame, they make a template according to which all the rafter legs for the hanging system are assembled on the ground. To create a sample take two thin boards of equal length rafters and fasten at the ends with a nail. This workpiece is set to the width of the girder, and the resulting angle is fixed by pieces of the board.

For marking the mounting gouges in the upper and lower rafters, the second template is used. Its basis is plywood. When collecting your legs, you need to strictly follow the pattern so that you do not have to redo the structure. The upper part of the rafters is connected with a wooden or metal plate.

If the assembled trusses have a significant weight, you will have to use equipment or devices for lifting.

The first pair of rafters is installed on opposite gables. It is fixed by temporary struts and exhibited by level. A cord is drawn between the legs as a guideline for installing the remaining trusses. The design is connected by bolts, struts and supports.

With a small span, the rafters are not fastened with a ridge girder. A roof with a width of more than five meters requires strengthening the structure with a ridge beam. This timber is fastened both under the rafters and above them. Connection occurs with gash and plates. With a large length of rafters, support posts are installed to prevent sagging.

Completion of the installation of the truss system will be mounting crates.

To know how to properly perform the truss structure, you can watch a video telling about the stages of work.

Video

The author of the video set a goal, without attracting professional builders, to quickly and affordably build a good, reliable roof with your own hands. What he did, you will learn by watching the video: