You will commonly see flat roofs on ranch style homes that were built in the mid 1950s to late 1960s. Flat roofs are notorious for drainage issues and should be monitored for standing water and debris, which can damage the roof and shorten its lifespan. Ponding water can dangerously increase the weight load of the roof and eventually compromise the entire structure. In addition, ponding water can lead to mold and mildew growth, staining, and leaking. This is why pitched roofing is recommended instead.
This type of roof is nearly horizontal. A roof that is completely horizontal is not recommended because it cannot carry the weight of inclement weather. Water and other objects that hit the roof will run off the roof from a minor camber or inclination into the home or buildings gutter system or straight off the roof. This type of roof is designed to accumulate water in a pool, most likely for visual or aesthetic purposes, even rainwater buffering.
However, if you do have a flat roof there are things you can do to prolong its lifespan and ensure the integrity of the overall structure, such as installing ISO board.
Homes that were built anywhere from 1940 to the early 1980s may have low slope roofs. This type of roofing can cover the entire home, not just additional structures.Homeowners who build additions, like overhangs or porches, often choose to have low slope roofing due to the fact it never requires them to change the original roof. If a person was to build a brand new roof that had the same slope as their old roof, it would cause a huge remodeling project. This isn’t the only problem with low sloping roofs. They have a tendency to develop leaking problems before higher sloping roofs, and it is much harder to trace the origin of those leaks, as well. Water loves to pool on low-lying roofing instead of running off quickly, and this is perfect for causing leaks and other types of problems.
Conventional/Steep slope roofs gained popularity in the 1980s and is typical of new construction homes. This is the more visually appealing slope because of its critically aesthetic components, especially in the residential area where a roof can be more than 1/3 of a home’s visual experience. Conventional / steep slopes generally last much longer than other types because they will shed much more water efficiently and are subjected to less U/V direct light.