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:
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.
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 March 2017 issue of College Planning & Management.