What is one potential cause of cracking in EPDM roofs?

Cracking in EPDM (Ethylene Propylene Diene Monomer) roofs can be significantly influenced by sustained exposure to UV light. EPDM is a synthetic rubber material that offers good resistance to weather and aging, but prolonged UV exposure can lead to degradation of the material. This degradation can manifest as cracking, as the material becomes less flexible and more brittle over time.

In contrast, the other options mention factors that may contribute to various forms of damage or deterioration but do not primarily cause cracking. Heavy foot traffic can lead to wear and potential punctures but is less directly related to cracking itself. Discoloration due to oil may affect the appearance and possibly the integrity of the roofing surface, but it does not specifically cause cracking. Improper installation techniques can lead to a range of issues, including leaks and sagging, but the root cause of cracking is more closely associated with environmental factors such as UV exposure. Thus, understanding the impact of UV light on EPDM helps in identifying and mitigating potential cracking issues in roofing systems.