A roof is not mere covering on the topmost part of an edifice. It is a must-required shelter for a building, its dwellers and its contents protecting them from the effects of atmospheric adversity. A shield to resist sunlight, rain, snow and wind, a roof is of several types depending on the variety of roofing materials, building structures and geographic conditions. The roof of a garden conservatory should be protective against rain, cold and wind but let sunlight pass through it. 
The features of a roof vary with the purpose of a particular building structure, availability of roofing materials, local construction systems and architectural design concepts. Many mistake roof types for roofing materials. The roof type is determined when your home roof is designed and constructed. Here is a brief note on the basic roof design types for common architectural designs of buildings.
Flat Roof
It is easier to build flat roofs than any other roof. Fewer materials and less labor are required for flat roofing than any other roofing type. That is why the roofs that are commonly installed on commercial buildings are flat. It is no wrong to call flat roofing commercial roofing. Generally, a flat roof is not much attractive as other roofing structures. A flat roof in modern style may be found on modern day, multi-family residential apartments.
Gabled
A classic gabled roof comes with two slopes that form a peak or a ridge at the top. Gabled roofs are braced property so that they can prevent the collapse or damage of the buildings because of high winds. In case of a triangular roof for residential and commercial buildings, the gable does not let rain and snow accumulate at all.
Cross Gabled
Somewhat akin to gabled roofs, a cross gabled roof comes with two gables crossing each other. Typically designed for Tudor as well as Cape Cod style homes, cross gabled roofs require more of construction materials and much of labor. Front gable roofing is a gabled roof type.
Gambrel
Gambrel is a flat gable roof type. Residential roofing for homes built in Dutch colonial style and American farmhouses, gambrel roofs resemble a bell in look from the side view. This roof type may be side or front facing.
Hipped
Common to be found on bungalow style residential houses, a hipped roof slopes down from all edges of a building. It is usually built low-pitched to let rain and snow run off easily. Such a roof type is more competent than gabled roof types to withstand the impact of high winds. Cross hipped and pavilion hipped are two principal hipped roof types.
