Roofs that appear flat often contain a low slope. For example, "flat" commercial roofing can be sloped nearly two degrees-a measure that brings significant benefits. Flat roofing that contains a slope lasts longer and is easier to maintain, two qualities that any building owner wants in a roof. If you are considering implementing a low slope roof, but have questions about its efficiency, the answers below can help.
Why is a slightly angled roof better than a flat one? Flat roofs allow pools of water to collect above sagging roof decking. As roofs age, these pools can gradually see through their coating and water barrier, causing leaks and water damage. In cold weather, standing water can form ice dams that prevent water from draining, resulting in pressure that could cause decking to sag or collapse.
How much does a low sloped roof cost compared to other designs? The cost of a rooftop is based on three factors: surface area, materials used and labor required. With that said, flat roofs, which require fewer materials and less construction than pitched roofs, are quite affordable new. But replacing them can cost more than replacing pitched roofs, which may require only felt underlayment and shingles or tiles.
How many low floor slopes are available? Some companies offer up to six types of roofing technologies for "flat" roofs: energy efficient thermoplastic polyolefin (TPO), ethylene propylene diene terpolymer (EDPM) that is applied in an adhesive sheet, vinyl single-plys, hot moped tar roofing covered with gravel, modified rubber bitumen roofing, and roled roofing that has a mineral surface. Some of these solutions work better for some buildings than others.
Can a slightly angled roof be used as a green roof? As they have their own design elements, green roofs are not simply placed on an existing rooftop. While they do require a rooftop that is basically flat, their support requirements extend deeper than roof pitch. Garden rooftops should be pursued for their own merits, not simply as an aesthetic addition to a flat roof.
How much maintenance do low sloped rooftops require? With the best materials in place, maintenance inspections may occur twice annually. For example, a high quality ventilation system, drain guards and topcoat should be in place if inspections are conducted twice annually. Under standard conditions, light commercial roof repair and maintenance are performed thrice yearly.
What are the disadvantages of a low sloped rooftop? Ice damming, high replacement cost, leaks, increased interior heating in the summer and frequent maintenance are disadvantages associated with low sloped roofing. However, these problems can be reduced or eliminated with the application of the right materials and design techniques.
Is it possible to keep repairing a flat roof instead of replacing it? When the right materials are used and proper maintenance is performed, repairs can reserve a flat roof for an extended period of time. As designs go, garden and concrete rooftops tend to age the best, with the former improving a roof's lifespan by up to 100%.
