By David Lukiiza
Gable roofs are the most popular roof types in Uganda, because they are considered traditional.
Indeed, the truth of the matter is that they have been here for decades. “Gable” is the top end of the wall of a building, in the shape of a triangle, where it meets the sloping parts of a roof.
Therefore, Gable roofing appears in triangular shapes with a slanting peak. However, such kind of roofing is now phasing out because of new architectural and aesthetic designs that are on the market.
Today, property developers prefer flat-roofed homes. Moses Kinobe, a construction expert, says flat-roofed homes originate from architectural designs in the desert.
FLAT ROOFED HOMES
Kinobe says many Ugandans have embraced this kind of roofing because of its decorative appearance. Engineers and builders construct buildings according to a client’s desired design.
Although some people may describe such a house as one without a roof, in actual sense the house does have a roof, only that it is separated by a parapet wall. A parapet wall, according to Kinobe, is a low wall constructed above the roofline that spans around the perimetre of the building.
Kinobe adds that a parapet wall may be purely aesthetic or primarily functional. For example, it may be hiding walloping mechanical equipment or working as a firewall.
However, since a flat-roofed home has a parapet wall, which is vulnerable to moisture penetration, it is better to choose an appropriate cap to eliminate moisture infiltration.
Capping the top
Fred Lubinga, a senior quantity surveyor at the education ministry, says there are a variety of materials used to cap off the wall, such as lime stone, terracotta, hard-fired clay or precast concrete. “Such materials are preferred because, compared to those made with brick and concrete, they have thermal properties.”
He explains that a flat-roofed house must be protected from harsh weather conditions such as a rain. “Because the entire roof top is capped off, water should be channeled off safely to the ground using properly installed gutters.”
Lubinga adds that if the walls are not protected and water is not drained off properly, they will be damaged, leading to possible collapse of the building. To avoid leakages, flat-roofing should be constructed by an expert.
Reasonable wall heights
Juddie Sonkaynar, the director of Artech International Kampala says the wall heights of the entire building should not exceed 9ft and 1/8 inches. “This makes the walls firm and stable.”
Sonkaynar explains that depending on the aesthetic and architectural designs one desires, the house must have a large overhang to protect the exterior doors and windows against rain and too much heat from the sun. Gumisiriza Birantana of Pearl Engineering Company Limited says, Large overhangs make it hard for water to hit the windows and doors directly, which may cause rotting and damage, which is not the case with no or short overhangs.
Gumisiriza, however, notes that while it is impossible to stop all wind-driven rain from reaching your walls, windows and doors, wide roof overhangs make a big difference, especially for storeyed buildings.
Can a gable roof be changed into a flat one?
It all depends on one’s income levels. Muwonge says one can change a gable-roofed house into a flat-roofed one. However, to avoid damage on the parent structure, an expert should replace the roof system.