The minimum slope of the roof of the professional sheet -

Decking is a practical, inexpensive and durable material, with the help of which it covers the roofs of low-rise private houses, garden or farm buildings, industrial buildings. Roofs made from this material are renowned for their reliability and corrosion resistance. With proper calculation and installation, this design can last up to 20-25 years. The key to a long service life of profiled sheeting is considered to be the correctly chosen angle of inclination of the roof, on which the efficiency of water drainage and snow removal from the surface of the slope depends. In this article we will tell you about the recommended and minimum slope of the roof from the profiled sheet, which provides sure waterproofing of the structure.

Characteristics of the material

To choose the right angle of inclination of the roof from corrugated board, you need to know the technical and operational properties of this material. It is made of rolled rolled steel with a thickness of 0.5-0.7 mm, which in the production process is covered with a zinc alloy and a polymer or paint coating. Using a powerful roller on the surface of the steel sheet, a trapezoidal or rectangular profile is extruded. The profiling process increases the strength and carrying capacity of this roofing material. There are 3 professional leaf categories:

1. Wall. This category of corrugated board is made of very thin steel and has a small profile height. The wall profiled sheet is cheaper, and is used for wall cladding, making fences and fences, building roofs with a small area.
2. Carrier. The bearing profiled sheet is supplied with additional stiffening ribs, which increase the load-carrying capacity of the material. It is made of thicker steel billet, has a profile height of up to 114 mm. It is used for the construction of garages, hangars, installation of floors and the creation of roofs with a large area and the distance between the rafters.
3. Universal. The universal profiled sheet has average characteristics that make it possible to use this material for most construction tasks. This type of coating is marked with the letters "NA"

Note! According to construction standards for arranging overlappings, the use of profiled wall, carrier and universal type sheets is allowed as a roofing material if the height of the material profile exceeds 20 mm and the roof slope is at least 8 degrees.

Slope selection factors

For non-professional builders who are unfamiliar with building codes, it often seems that the slope of the roof is chosen from the profiled sheet only in accordance with the architectural style of the building and the taste of the customer. However, this approach is a gross mistake, because the choice of this important indicator is influenced by factors that can be divided into 2 groups: technical and mechanical. The technical factors that take into account when determining the angle of inclination of the roof of corrugated board are the properties of the material itself. Climatic factors include:

• Determining the angle of inclination of the roof from the profiled sheet, first of all take into account the snow load. In regions where a large amount of snow falls, structures with a slope of 20-25 degrees are made to prevent the formation of a snow cap on the surface of the slopes.
• An important factor that is taken into account in the design process of the roofing structure is the amount of rainfall. The more rainfall in the construction region, the steeper the angle of the roof.
• Also the wind load influences the slope of the slopes from the profiled sheet. If in the construction region strong, gusty winds are blowing, then the roof is made more flat in order to reduce the windage of the structure.

Important! When determining the roof slope, the most important factors are the recommendations of the manufacturer of the roofing material and the climatic conditions in the construction zone. After this, a design project is created reflecting the composition, cross-section and mutual arrangement of the truss system elements.

Minimum slope

According to building codes, the minimum allowed slope of the roof made of profiled sheet is 8 degrees, provided that the installation of a solid or partial lathing. However, experienced roofing masters say that, observing some special conditions, this material can be laid on more gentle slopes. If the angle of the roof is less than the recommended overlap between the sheets increases, and the horizontal and vertical joints are treated with silicone sealant. There are 3 types of roofs from a professional sheet:

• Low sided. If the angle of inclination of the roof of the profiled sheet is less than 14 degrees to increase the waterproofing properties of the coating, the horizontal and vertical overlaps increase to 20 cm, make a frequent or continuous crate, use membrane material to protect the rafters from moisture. Each sheet of material overlaps the previous one by 3 waves, which reduces the effective area of ​​the material, increasing consumption.
• Medium carbon. If the slope of the roof is 15-30 degrees, then the overlap between the sheets of corrugated board is 15-20 cm, which corresponds to 1-2 waves. This slope of the slopes allows you to save money on roofing by increasing the effective area of ​​the sheet.
• Steeply. If the slope of the roof exceeds 30 degrees, the installation of corrugated sheet allowed a minimum overlap of 10-15 cm, corresponding to 1 wave of material. At the same time for the flooring, you can use a lattice crate with a step of up to 25 cm.

Consider that a clear pattern is observed when laying profiled sheets: the smaller the angle of inclination of the construction slopes, the more overlap is required between the sheets in order to protect the roof from leaks in the joints and tearing off the material by gusts of wind.

Dependence of the type of batten from slope

Industrial buildings are most often overlapped with a flat roof type, household ones with a single-slope type, and residential buildings with double-slope, hipped and four-slope ones.  Regardless of the type of roof construction, the coating should be laid on a reliable foundation that can withstand intense loads, and evenly distributes the weight of the corrugated flooring. The slope of the roof of corrugated has an impact on the choice of type of crates:

1. If the height of the profile of the material does not exceed 20 mm, and the slope of the roof is less than 15 degrees, then to ensure reliable support, a solid base and a cut board with a thickness of 2-3 cm are mounted.
2. If the profile height is more than 35 mm, and the roof slope is also less than 15 degrees, mounting of the grating base is allowed, the step between the boards in which is 30 cm.
3. If the profile height is 44 mm or more, and the slope of the roof exceeds 15 degrees, an edging board 2-3 cm thick, nailed with a step of 35-50 cm, is used for mounting the batten.

Note that any roof of corrugated, no matter how steep the angle of slopes, requires the installation of a drainage system consisting of gutters, funnels, pipes, which is responsible for collecting and transferring rain or melt water to storm sewers.

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