Gable roof system 2

12-04-2018

Useful

The gable roof thanks to a simple, reliable and presentable design has been popular for many years. Depending on the slope of the slopes, it is used in regions with different amounts of precipitation. The rafter system of the gable roof provides a natural gathering of precipitation.

Gable roof models

Symmetrical - both slopes have the same length and are mounted at the same angle. Such a roof is an isosceles triangle with a blunt or acute angle.
The broken roof is created to accommodate the attic room, its truss system implies a complex, two-level structure.
Different angles of slopes - this is the original design, emphasizing the unusual architecture of the house.

Tilt angle

The angle of inclination is selected after analyzing several indicators: the type of roofing, amount of precipitation, wind load. For regions with heavy rainfall, a small angle of slopes is recommended, but not less than 5 degrees. Snow masses do not linger on a steep surface. Flat roofs with a blunt angle of slopes are suitable for a windy climate.

The rafter system of a gable roof must comply with accepted safety standards and be built according to standards.

Rafter systems

Bearing elements and rafters take over the load from external forces and redistribute it to the walls of the building. From their reliability depends on the strength of the entire roof. When constructing a structure, two rafter device systems are used:

Hanging - truss feet have two points of support on the walls of the building. They experience a strain on compression and bending. When the distance of the span, exceeding 8 meters, the installation of the headstock with struts is required. To reduce the impact of rafters on the walls of the building, they are connected by pulling.
Suspended - these bars have a support on the inner wall or a special design.

If it is impossible to use one of the systems in its pure form, they resort to a hybrid design that allows alternating hanging and rafters.

Calculation of materials

The device truss system gable roof allows you to carry out the calculations on their own, based on knowledge of geometry. To calculate the area of the structure you need to set the length of the slope. The amount of material required depends on the angle of inclination. The acute angle allows you to save, but at the same time minimized the attic space.

The height of the ridge, the length of the rafters and the area of the roof will be calculated using geometric formulas. For clarity, fit scheme houses. Example - let's take the slope of a slope at 45 degrees, the width of the house (the base of an isosceles triangle) - 6 m, length - 10 m.

First, divide the triangle in half by the height lowered from the top corner. It turns out two right-angled triangles, and one of their legs is the desired height of the roof. The height divides an isosceles triangle in half, which means that one leg is 3 m. We calculate the second one using the formula:

3 ? tg 45⁰= 3 m

Knowing the legs, according to the Pythagorean theorem, we calculate the hypotenuse, which is a rafter:

3² + 3² = X² .

The length of the rafter will be equal to the square root of 18, approximately 4, 25

The number of rafters is calculated by dividing the total length by a step (0.6 m):

10: 0,6 = 16,6 - this value needs to be doubled.

The area is calculated by multiplying the length of the ramp and the house and multiplying the value by 2:

4.25? 10? 2 = 85 m².

Using various formulas, you can calculate the required amount of materials.

Installation of truss system

The basis for the roof is the mauerlat, a durable timber with a cross section of 150 × 150 mm from treated coniferous woods. Its attachment is performed on an anchor, immured in the upper row of the masonry. They must rise 2-3 cm above the beam to provide a place for tightening the nut. A ruberoid layer is laid under the mauerlat to protect it from moisture. Between the walls is laid transverse timber, fastening the mauerlat and protecting against longitudinal loads. To maintain the ridge, a special timber is laid along the slope - a lay, with a section equal to the mauerlat. With a significant width of the building installation of runs is necessary.

The cross section of the rafter is determined by the pitch and length of the rafter element, usually it is 50–150 mm. Roof trusses are easier to assemble on the ground and ready to serve on the roof. For the template are taken two boards, equal in length to the rafters, and are connected with a nail. The free ends are laid on supports, the resulting angle is fixed with a crossbar. Places and the shape of the gash are marked with the help of the second template made of plywood. Bars are fastened at the right angle with bolts, they are washed down, and after the truss they are lifted up for mounting.

The first set of rafters on the gables. They are attached to the mauerlat with the help of corners or brackets. The first farms are set strictly on the level. A cord is drawn between them, which is a guideline for installing the remaining elements.

To give sufficient rigidity of the whole structure to the rafter leg are attached to the struts and girders. The ridge girth is bolted to each truss. This connecting element should be made of durable timber.

With a significant width of the building, the installation of girders is necessary; it is a horizontal bar of 50 × 150 mm in size, supporting rafters. For its installation install vertical racks, based on the ground. These elements will form the basis of the framework for the attic.

In order to avoid water running onto the walls, it is necessary to provide an overhang; for this, the rafters are made hanging down 30 cm or additional boards are attached.

A crate is filled on the finished rafters, the necessary pitch is selected for each roofing material, and solid shingles are made for shingles. Warming of the roof is an important part of the construction. You can reduce heat loss to a minimum by correctly laying the insulation. Basalt wool is taken for this purpose, the width of the material is equal to the step between the rafters, which allows you to quickly and reliably perform insulation. Laying waterproofing will help to ensure reliable protection of the roof from moisture.

The symmetrical model of a gable roof is the easiest to build and reliable in use option. The load in the roof system is distributed evenly, which allows to extend the service life of the structure. Visual video lessons will help to master the subtleties of work.

Video

This video explains how to build a gable roof system:

In this video you can see the truss system on the example of one gable roof: