METAL TILE

Metal tile, which we referred to the category of the newest roofing, is quite known in our country. Metal-tiled roofing has gained popularity due to its look, reminding of tiled roof according to its colour and profile. Metal tile is made of rolled zinc-coated steel, which is covered by polymers. Producers buy this steel (with polymerous covering already) from metal processing-plants and produce metal tile using the method of rolling of steel and cold punching next.

THE SPHERE OF USAGE

Metal tile is used both in a new building and repairing. In the west metal tile is generally used as a roof covering for small premises of practical function: petrol stations, stores, practical premises. In private building it is not practically used. When repairing old roofs it is not necessary to reassemble the previous covering. But to avoid corrosion it is necessary to avoid a direct contact of zinc-coated steel and bitumen. Metal tile is not recommended to install on the roofs with an incline less than 14 degrees.

THE TYPES OF METAL TILE

The variety of goods, supplied on the market, differs by the geometry of profile (width and height of a wave, the design of tile etc); types of polymerous coverings, colour palette. The equipment, used for the production of metal tile, defines the geometry of profile. All the machines, though not significantly at times, differ from each other. For more convenience each of them (and respectively each profile) is given a trade name, for instance "Monterray", "Cascade", "Elite", "Classic" etc. A customer must know all that to understand that a name of metal tile is just the geometry of profile. Polyester and plastisol are used as a front layer of a polymerous covering for the production of metal tile. A colour palette of metal tile, which is offered by producers, is rather diverse. It depends on a colour palette of a producing plant.

ADVANTAGES AND DISADVANTAGES

The main advantages of metal tile are: small weight, easiness in assembling, various colour ranges, ecological safety and a reasonable price.

A disadvantage of metal tile is an increased noise during rain or when it is windy. When fastening metal tile one has to violate surface protecting polymerous layer. As a protecting layer is violated, a potential corrosion-dangerous zone is formed. Besides, the majority of sheets always have a big line broadening, consequently, the constant shaking of support will always take place at fluctuations in temperature. That is, supporting holes will be constantly broadening. These broadening holes must be painted over with some mastic as the time passes. Heat conductivity of metal tile is also high. Consequently, good warming is necessary for life. There is one more peculiarity of this material, which must be taken into consideration: it is increased forming of condensate on the lower surface of sheets (a dew-point is placed on this very surface). The formation of condensate causes, for instance, an overfall of day and night temperatures. Condensate is formed in such quantities that it becomes necessary to draw it outside. If you do not do it, water will leak from the ceiling in the attic. Both the ceiling and the floor are ruined, to say nothing of furniture, and truss system is beginning to rot.

Firms producing metal tile have more and more problems with the roofs with the covering made of PVH. Plastic colouring PVH of plastisol begins to break off after 10-year service. Particularly it is seen on black and brown roofs, which do not bear ultra-violet rays and warmth; red roofs become dull, they form dross, and the colour is dissolved. The problems are connected first of all with old roofs. The problems are connected with heat resistance of plastisol PVH, it can bear the temperature till 60 degrees. Its only advantage is thickness and the fact that it is not scraped as easily as other coverings. Cracks and breaks off are caused by the fact that plasticizers evaporate and PVH loses its elasticity. After that water gets into a crack, contacts with a zinc layer on the surface of tin and separates a covering from basic colouring.