Environmental Damage to Your Commercial Roof

September 15, 2020

The roof on your commercial building takes some serious abuse. It’s built to last (just not forever). Exposed to the elements, your roof is a first line of defense in protecting your building, but Mother Nature can be brutal. Let’s talk about what your roof endures and the wear and tear that results.

Heat and UV Damage

Long-term ultraviolet (UV) radiation exposure can result in cracks in the roof system. On modified bitumen and built-up roofs, this can make the roof look like alligator skin. This surface damage happens when oil leaches out of petroleum-based roof systems. If not repaired at the onset, leaking can be widespread and early replacement of the roof will be necessary.

a roof membrane with cracks in an alligatoring pattern

Heat and UV can also cause EPDM and modified bitumen roofs to shrink, pulling the flashings at curbs, penetrations, and walls. The result is splits and cracks that lead to leaks. Use of ballast or a coating can prevent UV from heating the membrane and causing shrinkage.

Destruction from Pests

Cracks and crevices provide an entrance for insects, rodents, and birds. If your roof has ponding water, grain, or residue from food processing, it’s providing a food source to these pests and your roof will suffer damage as a result.

Birds can be especially destructive to your commercial roof membrane.

Contract with a pest remediation service at the first sign of an infestation or avian population. Rodent tracks/paths, nests, gnawed materials, and droppings are sure signs it’s time to call in the professionals.

Damage Due to Inclement Weather

Dramatic swings in temperature and snow, hail, wind, and rain can all wreak havoc on your commercial roof system.

As one season gives way to another, a cycle of freezing and thawing can damage your roof membrane. Water that infiltrates, expands when it freezes. Roof damage resulting from contraction and expansion can include any of the following:

black roof membrane with a small puncture

Driving rain or a long soaking downfall can lead to leaks (and wet insulation), as well as ponding water. If hail accompanies a storm, expect punctures and splits. Damage to the roofing membrane is especially problematic at the fastener in the membrane seam. Even the insulation layer can take a beating if hail is large enough or falls with enough force.

Gusts or sustained periods of strong winds can drag tree limbs, debris, obsolete equipment, and dislodged roof elements (e.g. vents and roof hoods) across the field of the roof; punctures, tears, and abrasions are left it its wake. In extreme cases, wind uplift pressure can result in edge metal damage and even cause the entire roof to blow off.

Just like an excess of ponding water can test the integrity of the roof, so too does snow load. If a significant accumulation exceeds the structural capacity of the roof, collapse is possible.

The Problem with Dirt and Leaves

An accumulation of dust and dirt can reduce the solar reflectivity of reflective roof membranes, as well as dramatically reduce the energy output of rooftop photovoltaic panels.

When dirt and environmental debris collect, it provides the ideal environment for biological growth (e.g. algae, mildew, and mold) and vegetation. Environmental debris can impede proper drainage (leading to ponding water and leaks); saturated leaves and dust can also become rooftop compost and allow wind-borne seeds to take root. The root system of plants, shrubs, and trees will quickly destroy a roof membrane and the insulation beneath.

Trim nearby trees and remove dirt and debris on the roof once or twice a year as proactive measures. General preventive maintenance will help you keep your roof clean.

You can’t control nature or the weather, but you can prepare your roof for it with proactive maintenance and regular roof inspections.


Call D. C. Taylor Co. at 319.363.2073 to schedule general preventive maintenance today.

Contact Us Today To Get Started On A Quote