Most modern public and residential buildings are covered with metal roofing materials. These include metal tile and corrugated roofing sheets. They are made using similar technology, so the difference is only in the form of a picture. If the former it is made in the form of tiles, the latter has the appearance of longitudinal ridges imitating slate. In order to better understand what type of corrugated roofing sheets to choose for a roof, you need to study its varieties and understand the meaning of marking.
Classification of corrugated roofing sheet
A corrugated roofing sheet is produced by cold rolling of a metal sheet. The product has a comb surface. This gives rigidity and allows water to flow along the grooves formed by the ridges. The ridges can have a different geometric cross-section, starting from a triangle and ending with a trapezoid. This does not affect the mechanical properties, but creates a variety when choosing a material. Therefore, it does not matter which deck to choose for the roof: with triangular or rectangular ridges. This is simply a matter of consumer taste.
Types of protective coatings
The profiled sheet after the rolling mill enters the workshop, where it is protected by galvanic treatment. There are two types of protection:
- zinc coating involves the use of zinc salts as a working substance. As a result of electrolysis, metallic zinc settles on the sheet, covering it with a continuous layer. This metal interacts poorly with oxygen, which guarantees excellent corrosion protection of steel. The more zinc was spent, the stronger the protection;
- aluminum-zinc coating is produced by the same technology, only aluminum salts are added to zinc salts.They are cheaper, so this coverage is more budget. At the same time, the degree of protection is reduced, which makes it necessary to make another decorative coating of polymeric materials and dyes.
The top color coating is more likely a decorative function, since it is not very durable. However, it is able to slightly enhance the basic defense.
Useful advice! You need to be careful when installing the roof from corrugated board, as this coating can be scratched. Scratches will be clearly visible on the surface, which will reduce the presentability of the object.
Types of decorative coatings
Decorative coating is also of several types:
- glossy polyester is the easiest and cheapest coating option . During installation and operation, it quickly loses its appearance due to scratches and chips;
- matte polyester has great reliability and resistance to mechanical stress. Its structure is like velvet, and its thickness is greater, which allows it to preserve color longer and not give glare;
- pural is a polyurethane, with the addition of polyamide, a coating having a thickness of 50 μm. It has high reliability, immunity to low air temperatures and ultraviolet rays. Pural is best suited for application on roofing sheets;
- Plastisol is the most reliable of all types of coatings. The thickness of the polyvinyl chloride layer is 200 microns. Such a coating of polymers has embossed embossment and a dashed notch. It is intended for operation in harsh climatic zones, has resistance to mechanical stress, and is very durable.
All these coatings are applied to a layer of paint, which can be of various colors. The name of the color may be different for different manufacturers, but the most common are shades of red, brown, blue and green. You can find bright orange, yellow and purple options for corrugated board. Which flooring to choose for the roof of his house, each owner decides according to their color preferences.
Types of corrugated roofing sheets as intended
Based on the scope of the material, the following types of profiled sheet can be distinguished:
- Roofing (R) is used only for roofing. It has a profile height of more than 20 mm, and a wave height above 44 mm.
- Bearing (B) is used in the construction of frames of various stalls and trade pavilions, sandwich panels and ceilings. It has a wave height of 35 mm.
- Wall and bearing (WB) has a universal purpose. Bearing structures are made of it, they are facing walls. The wave has an even greater height (35−44 mm.).
- Wall (W) is used only as a facing material for walls. Its profile is from 6 to 35 mm in height.
All types of corrugated board are cut into standard sheets from 1.5 to 12 m long. At the same time, at the request of the customer, manufacturers can cut sheets of any desired length.
Useful advice! In order not to make a mistake in the amount of material needed to close a complex roof, you need to buy 10-15% more. If the sheets are of standard length, surplus can always be returned to the store.
Which decking to choose for the roof
Before you start choosing roofing material, you need to learn the following important things that you should pay attention to when buying:
- when calculating the area of the roof, it is necessary to take into account 200 mm tolerances;
- Do not buy too cheap non-galvanized sheets that quickly rust and collapse under adverse environmental conditions.
Useful advice! For the roof, only a roofing sheet with a wave height of at least 20 mm will fit, while the more precipitation falls in a particular area in winter, the higher the ridge should be.
So which roof decking to choose from the listed options? Experts advise making a choice taking into account the region of residence, as climatic conditions are crucial in choosing.
Among the main options for corrugated board with which you can cover the roof, there are:
- R20 – is used in roofing in the zone of moderate rainfall. It is necessary to install a battens with a step of no more than 80 cm. The sheet has a working width of 110 cm
- W21 is a wall profile, but it can be used for roofing in the temperate zone. The step of the crate is also not more than 80 cm.
- WB35, 44 are used in more severe climatic conditions, since they have a greater permissible bearing load.
In addition, B-57, 750 (900), B-60, 75 are used in roofing works, depending on the required load bearing.
If a question arises, which roof decking to choose, do not deduct such parameters as colors and decorative properties. After all, the roof, in harmony in color and texture with other buildings on the site, looks much more attractive and creates the impression of the integrity of the entire architectural environment.
Features of installing corrugated roofing sheets for different types of roofs
The general rules for installing roof decking are as follows:
- the crate is made continuous or in steps, but no more than is prescribed for a particular brand of sheet;
- film or roll vapor barrier is placed on the crate;
- sheets are fastened with special roofing screws with rubber gaskets along the waves.
For different types of roofs, the rules are slightly different. So, flat roofs begin to close from the right edge. The installation of tent-type roofs is carried out simultaneously from two sides, and begins from the highest place of the slope.
Useful advice! It is better to close complex roofs with corrugated board than with metal tile. It does not require alignment in length, which greatly saves material.
If you correctly decide which roof decking to choose and lay it in accordance with the requirements, you get a beautiful and reliable roof.