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Commercial Low Slope Roofing


Commercial low slope roofing, commonly referred to as flat roofing, is usually found on commercial and industrial buildings, such as factories and warehouses. But many apartment buildings and townhouses have low slope roofs, too.

The terms low slope and steep slope describe roof slope. Slope is how much a roof slants or the incline of a roof. In commercial low slope roofing applications, the roof has a slope of less than 3 inches per foot. This means that for every horizontal foot, the roof level goes up less than 3 inches vertically. Steep slope means that the roof has a slope of more than 3-inches per foot. Roofs on most commercial buildings have at least a small slope of 1/4 inch per foot.

There is a good reason for roofs to have some slope – for proper water run-off or drainage. When it rains, water has to go somewhere, and that is why drainage is so important. Water should not stay on a roof. In commercial low slope roofing, water is directed to drains. Use of small areas called crickets and saddles can help direct water to the drains.

Drains on low slope roofs are located at the low points of roofs, called valleys. A valley is where two slopes meet at a low point. There are two types of drains: interior and exterior. Sometimes interior and exterior drains are used together. An overflow scupper is an example. A scupper is an exterior drain. It can handle water runoff if the interior drain gets clogged. Another drain that can handle overflow is called an overflow drain.

There are thousands of commercial low slope roofing configurations to choose from. There are numerous roof deck types, insulation requirements, roof membrane requirements and other factors complicating the selection. To simplify the process, a professional roofing contractor should be involved to assist in the selection of the appropriate commercial low slope roofing system for the particular application in new construction or replacement applications.

Innovative commercial low slope roofing solutions
CertainTeed leads the way in smart, energy-saving commercial low slope roofing products that help you meet new building standards. For instance, our CoolStar™products such as Flintlastic® SA Cap FR CoolStar® and Flintlastic® GTA CoolStar® with solar-reflective surfaces meet ENERGY STAR® requirements, can be used to comply with 2016 California Title 24 Part 6 Cool Roof Requirements, and offer several installation advantages.

Workmanship is key
To help assure the best possible workmanship for your commercial low slope roof installation, CertainTeed has established the Gold and Silver Star Contractor programs. These programs offer the building owner a selection of highly credentialed roofing contractors who have met the strictest criteria relating to financial credibility, workmanship history and sound business practices, including proper licenses and appropriate insurance.

Outstanding low slope roofing warranty options
Only CertainTeed Gold and Silver Star Contractors are eligible to apply for CertainTeed’s NDL (No Dollar Limit) and Integrity Coverage (IC) warranties on specific commercial roof projects. The three levels of IC warranties (see box below) are only available through CertainTeed Gold Star Contractors. Owners and specifiers who choose an IC option have the added security of manufacturer involvement in the maintenance and upkeep of each commercial low slope roofing system to maximize the life expectancy of the roof. Contact CertainTeed for complete warranty and maintenance plan details, including limitations and costs.