Despite the wide range of roofing materials, steel remains demanded finish coat for roofs of residential and process buildings. Its reliability and rather inexpensive cost is the reason for that.
What is roofing steel?
Roofing steel represents sheet material 0.5-0.8 mm thick which is received, according to GOST 14918-80, two methods of rolling: hot and cold. If the second is used, metal demands the subsequent roasting for increase in plasticity of leaf. The cloths rolled on continuous machines deliver in rolls.
Roofing steel happens two types: black (thin-sheet) and galvanized. The last is more popular as it possesses anticorrosion properties. From it not only mount roofs, but also make rain water pipes, buckets, tanks for water, garden and garden stock and also set of other goods.
Galvanization of steel is carried out in two ways: hot and electrolytic. In the first case the sheet of the metal which has gone out of the rolling machine is lowered in the container with liquid zinc. The electrolytic way of galvanization gives the chance to receive better steel cloth. In order that the protective layer was durable, its thickness has to be not less than 0.02 mm. The cloth of roofing steel can be both to the straight lines (flat) and corrugated with the different height of wave. In recent years with emergence in the market of metal tile and the pro-thinned-out metalprofile for finishing of roofs use sheet steel more and more seldom. It is caused by its simple exterior. Therefore today this material can be met generally on roofs of engineering buildings and farm buildings. Private developers choose, as a rule, color metal tile or metalprofile. These materials have roofing steel in the basis too, but are covered with stronger and durable polymeric structure which includes pigment for giving of certain color. The structure of these cloths is more complex as it includes several layers: steel, protective soil, zinc, protective paint, layer of color polymer.
Features of mounting of roofing steel
As thickness of protective layer of steel is only 0.02 mm, in transportation time, laying on roof and fastenings of cloths, it is necessary to observe safety precautions not to scratch covering from zinc. Any damage of this layer will cause inevitable emergence of corrosion that will demand repair of roof and will reduce the term of its service at least by decade. Cloths of roofing steel (both black, and galvanized) stack on furring from the bars with a section of 50/50 mm located at distance of 250-270 mm from each other. Sawn timber is mounted on waterproofing covering of roof. Most often for its device use roofing material.