What Causes a Flat Roof to Leak?

Many campus buildings feature flat roofing. Because there is no pitch, these systems rely heavily on a combination of product quality, membranes and initial installation. Some reasons your flat roofs may develop leaks include:

Clogged Drainage
A flat roof relies on a drainage system to remove rain water. If the drainage system is clogged, water will pond on your roof. Ponding water eventually leads to excess strain on the roof, and inevitably the water will start to seep inside.

Damage to the Perimeter Flashing
Flashing is installed on the edges of the rooftop as well as the interior parapets to protect the roof’s membrane. Moisture and water can seep underneath this flashing and into the building if it is not installed correctly, or becomes damaged.

Open Penetrations
Penetrations are common on rooftops, including as drains and pipes. When these are not installed properly, they leave a roof prone to leaks. They should be kept watertight with flashing, wraps, rain collars and pitch pans.

Damage to the Membrane
When a roof’s membrane becomes damaged, it allows water to enter through the opening. Membranes can become damaged for a variety of reasons. Sometimes it is just a matter of age.

The Age of Your Roof
Flat roofing in areas that experience hot summers or harsh winters will eventually start to fail due to age. Most systems deteriorate at about 15 to 20 years post-installation.

This article originally appeared in the issue of .

Featured

  • Philadelphia Middle School Facility Earns LEED Gold Certification

    The Alternative Middle Years (AMY) at James Martin Middle School in Philadelphia, Penn., recently received a LEED Gold certification from the U.S. Green Building Council, according to a news release. The School District of Pennsylvania partnered with KSS Architects on the project.

  • Arizona District Breaks Ground on Community Training, Learning Center

    The Tolleson Union High School District (TUHSD) in Tolleson, Ariz., recently broke ground on a new Training & Learning Center (TLC) for both district professionals and the community at large, according to a news release. The 90,000-square-foot facility has an estimated completion date of spring 2027.

  • Moline-Coal Valley School District to Consolidate Two Schools into New Facility

    The Moline-Coal Valley School District in Moline, Ill., recently broke ground on a new elementary school that will consolidate the students and staff from two existing schools, according to local news. Robert Ontiveros Elementary School will serve as the new home for Lincoln-Irving Elementary School and Willard Elementary School.

  • Designing Third Spaces That Do What AI Can't

    In 2026, education is evolving faster than ever. With AI reshaping everything from lesson planning to personalized instruction, schools and universities are turning their attention to what AI can’t replicate: spaces that foster collaboration, community, and creativity.