A roof can serve more functions than simply offering safety protection to providing plenty of ways through which one can maximize the available house space.
Throughout the history of mankind, shelter has evolved with the advancement in human activities from primitive, simple structures such as caves dwellings to more complex art forms and architectural designs which combine different elements of both the interior and exterior of the house to make a great finish and a visual appeal. One of the most quickly noticeable exterior elements of a house design is the building envelop, which relates to the design and construction of the exterior of the house.
According to architects, a good building envelop involves using designs that are appropriate to the surrounding climate, are structurally sound and have a pleasing aesthetical effect and, none among the building envelop elements instantly communicates these needs better than the roof of a building.
Other than offering protection against environmental hazards such as heat, wind and rain, a roof is the first thing that outsiders look at whenever they want to judge the quality of any construction. As such, a properly built roof will add value to the house as well as increase the integrity levels of the construction.
Evolution of Roofing designs
The modern-day roofing materials and design have come a long way. Most common however, are the flat and pitched roofing designs whose history is as long as that of mankind.
Earliest roofs constructed by man were thatched roofs made of branches, leaves and in some instances reeds. The roofs usually sloped or pitched to drain rainfall off them. Alternatively, thicker branches pressed with clay between them were also used to make flat roofs giving rise to the two main types of roofing designs; flat and pitched roofs. Other types of roofs include vault and dome designs.
Historically, flat roofs can be traced to the Middle East and parts of South America where they were predominantly used many centuries ago before migrating to the west, to provide insulation against the harsh desert heat. Later in the nineteenth century when new roofing materials such as steel and concrete gained popularity, flat roofs became widespread in Europe and the Americas among warehouses, office buildings and residential houses.
Unlike the flat roof design, a pitched roof is a two-sided sloped roof with a gable at both ends. This type of design is the most common and it comes in various varieties. Although the earliest designs of pitched roofs are attributed to ancient Greece during the construction of temples, history considers it a staple architecture in Europe and parts of America.
As the building and construction industry continues to advance, individuals are beginning to rethink the general impact of construction on the planet and how to best utilize the available and emerging technologies for a more comfortable and dignified living space.
Roof spaces are increasingly becoming popular among designers and constructors who are keen to maximize their utility without engaging in additional cost of construction. In the twenty first century, gardens, swimming pools and a host of other amenities have found their way on the roof top spaces to give flat roofs more recognition.
A flat roof is almost level compared to the pitched roof which slopes, and is most preferred in warmer climates and areas with less rainfall where freezing is less likely to occur. Most flat roofs are built with concrete masonry where timber is not readily available making them more cost effective. However, different waterproof materials have been used in modern development to improve durability of flat roofs.
Among the notable development on the flat roofing design is a Protected Membrane Roof (PMR) where a thermal insulation is located above the waterproofing layer. The PMR is important in protecting the waterproofing membrane from thermal shock and mechanical damage among other dangers.
Other than PMR, flat roofs have also witnessed green roofs which are made by depositing top soil on flat roofs and seeding them. The soil mass provides heat to the building storing heat of the sun and realizing it into the building at night to regulate the temperatures inside the house.
Pros and Cons
Whereas a number of merits have been attributed to the popularity of flat roofs such as stability against wind, ease of construction among other advantages, flat roofs also have their flaws. Proponents of this roofing design hail it for its security and safety. It is argued that is easier to make a flat roof more fireproof compared to pitched roofs.
Also, flat roofs provide the much need space which can be used for gardening, as a play area or a drying yard among many amenities. For constructors who wish to co build multi-storied houses, a flat roofing design provides an ideal choice to utilize the aerial space.
Unlike a pitched roof which requires a false ceiling, flat roofs have inbuilt insulating properties which shield the house from external heat.
One of major weaknesses of a flat roof design is its susceptibility to cracks on the surface of the roof when the variation on temperature is high. Cracks may lead to leaks which end up weakening the building. Compared to a pitched roof which can be used over a large span, flat roofs are limited in application for quality control measures.
In terms of cost, flat roofs are more expensive than sloped roofs.
Whether an individual homeowner or a constructor settles for either a flat or pitched roof design, the ultimate value of the roof to the structure depends on the maintenance of the roof. A well maintained roof will stand the test of time.