The roof in most cases has a factory protective layer, which protects against the destructive influence of external factors. Conventional ceramic tiles have a terracotta in connection with the presence of iron compounds contained in clay in it. It is not processed with a protective layer. Angobbled (matte) ceramic tiles before firing is covered with liquid clay with the addition of dyes to it. Therefore, it has a different color and, unlike ordinary and practically does not expose mosses. The glaze is applied to the glazed tile after firing and still burned. Such a tile practically does not absorb water. It is very easy to care for it: water from such a roof flows without delay, so mosses and lichens do not grow on the coating. Cement tiles are stained with a factory acrylic or acrylic-silicate paint, and therefore does not absorb water, has a smooth surface and fades slowly. The accumulated dirt is easily washed off with rain, the growth of mosses is prevented. The primitive layer of paint is applied to the liquid mass placed in the shape, and the next two – already on a completely dried tile. Metal roof is resistant to adverse factors due to various additives. In order to protect the sheet and give it color and brilliance, various polymers are applied to it: glossy or matte polyester, polyvinylidiftoride, purple, so the coating is the highest operational qualities. Among the metal coatings, the most durable is copper: from corrosion the roof protects the patina consisting of several layers of oxides. The main material for the manufacture of bitumen tiles is oxidized bitumen. Modifiers give bitumen small sensitivity to high temperatures and low. Wooden gont roofs are preserved from damage by impregnation. Every three years to process the roofs of reeds with fire -retardant impregnation. Galled sheets are subject to restoration as periodic tinting, and with each layer, their service life will increase.
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