Sloping roofs – general information

tmp107d-1The basic task of the roof is to reliably protect the building against the influence of external factors, however, one should not forget about the huge aesthetic function of the roof in shaping the appearance of the building. The shape of the roof depends on the shape of the building, architectural assumptions, type of coverage, intended use and geographic location. Regional traditions have a great influence on the shape of the roof, fashion and architectural trends. Among the complex roof forms, basic types of pitched roof shapes can be distinguished:

• Mono-pitched (otherwise desktop) -1 pour, 1 hood, 1 kalenica.
• Gable – 2 tracts, 2 hoods, 1 kalenica.
• Four-pitched (otherwise envelope) – 4 tracts, 4 hoods, 1 kalenica, 4 corners.
• Mansard – roof slopes broken in this way, that the upper ones are less steep and the lower ones more; the mansard roof can be double or hipped.
• Tent – as many roofs and eaves as there are sides in the building and the same number of corners converging at one point without a ridge.

Each roof consists of a load-bearing structure, primer under the cover and coverings.

The supporting structure can be made of wood, steel or reinforced concrete – from components made on site or prefabricated and imported from the factory. In Poland, traditional wooden truss is most often used.

The roof covering can be made of various materials:

• Light materials, e.g.. bituminous plates (3,3 kg/m2), Grandpa (4-6 kg/m2), tile sheets (5 kg/m2), bituminous tiles (8-15 kg/m2).

• Heavy materials, e.g.. cement tiles (36-46 kg/m2) and ceramic tiles (40-75 kg/m2).

The difference in weight between light and heavy roofing materials affects the roof structure used and the cross-sections of the roof truss elements and is an important point in structural calculations. The slope of the roof slopes depends on the type of material used, the possibility of shaping architectural details and the selection of a primer for the cover.