Is it true that the existing roof must be adequate as a base for additional roofing layers?

The assertion that the existing roof must be adequate as a base for additional roofing layers is true, as indicated by the correct answer. When adding new layers of roofing, it is essential that the underlying structure is sound. A sound roof provides the necessary support and stability needed to ensure the longevity and effectiveness of the new roofing materials being added. If the existing roof is compromised—whether by age, damage, or structural issues—it can lead to serious problems such as leaks, inadequate insulation, or even collapse of the additional layers. Proper assessment of the existing roof’s condition helps to prevent further complications and extends the overall lifespan of the roof system.

Other options suggest scenarios that could potentially lead to roof failure or inadequate performance, which underscores the importance of having a sound existing roof before any new roofing work is undertaken.