Slate is an inexpensive and affordable roofing material inherited from the Soviet era. This wavy gray coating has become a symbol of the flourishing of country and garden construction. In the conditions of fierce competition in the construction market, slate has survived among more modern, attractive materials due to the improved appearance as well as the performance characteristics of manufacturers. The peculiarity of working with this roofing coating is the large weight of slate, which must be taken into account when designing the roof and erecting the truss framework. In this article we will talk about the technical parameters of the main types of materials made of asbestos cement.
Composition and types
Slate is a material made from a mixture of asbestos, Portland cement and purified water, which is used for arranging the roof and wall cladding. In the production process, all the ingredients are mixed in the right proportion, laid out in a form, and then remain there until complete solidification. It has a high resistance to moisture and ultraviolet rays, does not burn, is not afraid of temperature changes. Depending on the shape and purpose, there are 2 types of slate:
- Волновой. Этот вид материала представляет собой кровельный материал с листами прямоугольной формы, которые в результате формовки приобретают волнистый профиль. Wave Slateиспользуется для настила на скат крыши, так как за счет желобов он лучше отводит жидкость. Производители рекомендуют использовать его, если угол наклона ската превышает 12 градусов. Учитывая, сколько весит шифер волнового типа, монтаж выполняется на усиленную обрешетку.
- Плоский. Flat slate, в отличии от волнового, не имеет характерного рельефа. Он представляет собой плоский лист из асбестоцемента в виде прямоугольника или квадрата. Этот материал чаще всего используется для обшивки стен, строительства заборов, а также для изоляции участков, контактирующих с элементами дымохода и теплогенерирующих приборов. Однако, плоский шифер иногда применяют как кровельное покрытие, если уклон крыши больше 25 градусов. Он обладает большей механической прочностью, высокой устойчивостью к низким температурам и влаге.
Note! The weight of slate, depending on the size and type of sheet, is 23-39 kg. This means that for 1 m2 of area there is a load of 9-17 kg without taking into account the weight of the insulating material. To make a coating of this material, you should take into account the possible mass of the roofing pie when calculating the foundation and truss frame of the house. Without the necessary margin of safety, the structure will collapse or skew.
Number of crests
Yet for the construction of roofs, wave slate is more often used. Manufacturers produce products of various sizes, so that it is suitable for private construction, which is dominated by small-sized buildings, as well as for the construction of industrial buildings of a large area. According to GOST, this type of product is distinguished from slate with a standard, unified and reinforced profile. But it is easier for customers to navigate according to a different classification, based on the number of waves in the sheet:
- 5 wave. Slate with 5 ridges on the surface is an innovation in the construction market, the effective use of which has not yet been found. The size of the sheet of this material corresponds to the size of the 8-wave, but due to the greater wave width, the effective coverage area is only 1.6 m2. It turns out that 20% of the surface of the material "eats" overlap.
- 6 wave. This type of slate is produced with a sheet size of 1125x1750 cm, 6-7.5 mm thick, and the distance between the ridges is 20 cm. It has a reinforced profile and a weight of 26-35 kg, therefore it is used for construction in regions with high wind loads, for overlapping industrial buildings of a large area.
- 7 wave. This type of slate with 7 ridges is traditional, therefore it has standard dimensions of 850x1750 cm, sheet thickness of 5.8 mm and weight of 23 kg. Due to the small surface area and light weight, 7-wave roofing made of asbestos cement is widely used in private low-rise housing construction.
- 8 wave. The slate dimensions of this variety are 1130x1750 cm, thickness is 5.2 mm or 5.8 mm, the useful area of the sheet is 1977 cm. It is used in industrial construction due to its impressive dimensions. The weight of each sheet is 23-32 kg, depending on the thickness of the material.
Important! Slate is considered a reliable and durable coating, it serves at least 20-30 years. This inexpensive roofing material withstands temperatures in the range of -50 to +80 degrees, does not burn. Cipher weakness - point beats, which can easily lead to a splitting sheet. This feature must be considered during transportation, storage, installation of asbestos-cement coating.
Knowing how much a sheet of slate weighs, it is easy to imagine how durable and bulky should be the roof truss system that you plan to cover with this material. Considerable weight is the main feature of work with asbestos cement roofing. Professional roofers offer 3 important tips to avoid problems in the operation of a slate roof:
- Make a project and perform calculations. Slate roof has a tremendous load on the roof frame, as well as the foundation of the house, so you need to calculate everything before you begin to install.
- Calculate the options. Slate is considered one of the cheapest roofing materials, however, the considerable weight of the coating makes it necessary to reinforce the foundation and roof frame. A large amount of concrete and high-quality wood are expensive, so sometimes it will be cheaper to buy a lighter and more expensive material (ondulin, decking, shingles).
- Do not forget the overlap. Inexperienced masters forget to take into account overlapping sheets when calculating the required amount of material and the total weight of the roofing pie. Because of this, an error creeps in the calculation of the carrying capacity of the frame, the result of which can be a complete collapse of the roof.
Remember! Slate is a construction product, which for the admission to the implementation does not require mandatory certification. Most manufacturers regulate the quality of their products not by GOST, but by their own technical regulations. Therefore, carefully inspect the appearance of the material when you purchase, so that the roof covering will last no less than the time stated by the manufacturers.