What is a key indicator for evaluating low-slope roofing systems for recovering versus replacement?

A key indicator for evaluating low-slope roofing systems for recovering versus replacement is the presence of signs of moisture, vegetation, or fungal growth. These indicators can reveal underlying problems that may compromise the integrity of a roofing system.

When moisture penetrates the roofing material, it can lead to structural damage, mold growth, and reduced performance of the roof. Vegetation and fungal growth often signal that there is prolonged moisture accumulation, which indicates that the roof may not be performing as intended. In contrast, if a roof exhibits these signs, it is likely that a simple recovery—applying a new layer over the existing roofing—would not solve the underlying issues, necessitating a full replacement instead.

While surface appearance, age of the roof, and type of roofing membrane can provide guidance in assessing the condition, they do not directly reflect the immediate and critical concern for water infiltration and its associated risks that are indicated by moisture, vegetation, or fungi. Therefore, these signs are crucial in determining whether a low-slope roofing system should be recovered or completely replaced.