How to calculate the height of the ridge and the area of a
Dvukhskatnaya roof is the most popular roofing structure, which equip private homes, baths, garages and other buildings. The construction of the roof of this type is a rational solution to the issue of protecting the interior from the penetration of precipitation, wind and cold. In the process of designing a dual-slope roof, the central place is occupied by the calculation of the height of the ridge, the determination of the slope and the area of the slopes. From these three parameters depends on the life and efficiency of overlap, so in this article we will describe how to independently calculate the main parameters and technical characteristics of the roof, not using the calculator.
Ridge connection functions
The ridge is the highest point of the double-slope roof, the horizontal edge, which is located at the junction of the ramp planes. It is mounted at the final stage of roofing, but before installation of the sheathing on the rafter legs. The length of the ridge of the gable roof corresponds to the length of the slope. This element of the truss frame solves the following tasks:
- The main function of the ridge is to support the upper part of the roof truss feet. It binds together all the pairs of rafters, giving the structure rigidity, evenly distributing the weight of the roof material of the gable roof.
- Ensuring air circulation. The air gap formed in the place of the skate equipment protects the roof frame from air stagnation and rotting, provides ventilation of all wooden elements, due to which the durability of the gable roof increases.
Important! In the process of designing the roof you need to choose and correctly calculate the height of the ridge. If the room located under the roof of the roof is used as residential, then the choice is made based on the desired ceiling height, in other cases, the calculation is performed based on the recommended angle of inclination of the slopes.
The easiest way is to make calculations using a special calculator program, by entering the initial data into which you can determine the height of the ridge, the area of the slopes and the under-roofing room.
Methods for calculating the height and area of the roof
You can calculate the height of the ridge and the area of the gable roof and other related parameters without using the calculator program. This requires knowledge of elementary geometric formulas, which, we hope, you did not have time to forget from school times. Independently calculate the horse can be two simple methods:
- Mathematical. This method is based on the formula for calculating the length of the leg of a triangle. If you imagine a double-slope roof in a vertical section, it forms an isosceles triangle. The height of the ridge is called the segment, which goes from the middle of the base to the top of the triangle (roof). To determine what this distance is, you need to use the formula: a = b x tg ?, where a is the height of the ridge, в is the distance between the slopes along the eaves,? - the angle formed by the base of the roof and slope. After completing the calculation of the height of the ridge, you can calculate the area of the pediment, as well as how much lumber is required for its sewing. The calculator uses the mathematical method to calculate.
- Graphic. The graphic method is based on the construction of a scaled drawing reflecting the length and width of the house, as well as the real slope of the sloped roof slopes. On a sheet of paper, draw a frontal projection of the box of the house, then use the protractor to measure the angle between the base of the roof and the ramp. The distance from the eaves to the ridge connection is measured with a ruler and translated based on the scale. For the graphic method of determining the height of the ridge, calculation is not required, but errors in its use occur at least.
Important! The most reliable way to perform the calculation of the height of the ridge and the area of the slope is a special online calculator. To use it, you need to enter the initial data: the length and width of the house, the slope of the slope.
Determining the height of the roof
The most important factors influencing the choice of the height of the ridge joint are related to the natural conditions of the area in which the construction takes place. According to building codes, this parameter is chosen based on the following conditions:
- The amount of precipitation. The more rainfall occurs in the construction region in the winter, the higher the ridge of the roof is located in order to get steep slopes, from the surface of which the snow slides off "by gravity." For central Russia, the recommended slope is 40-50 degrees. In order to teach this figure with a house width of 6 m, the ridge must be raised at least by 2.52 m.
- Type of roofing material. The nature of the roof covering surface is reflected in the recommended slope of the roof. If the surface is rough, then the angle of the slopes is increased to facilitate the descent of snow masses. If the roofing material is ugly, then the slope is chosen in the region of the lower limit of the recommended values, since increasing this parameter increases the area and weight of the slopes.
- The power of the wind. In areas where a sharp gusty wind prevails, hurricanes often occur, the roof slope is reduced to reduce the windage of the roof structure. A strong wind breaks the coating from the roof surface, reducing protection against moisture penetration.
Note! The height of the ridge connection affects the effective area of the attic. To equip a living room under the roof, it is necessary to raise the roof to a height of at least 2.5 m, however, this will negatively affect the usable area due to the low sidewalls.
