What is a critical issue regarding ductwork installation in rated roof assemblies?

The correct answer focuses on the critical issue that ductwork from roof-top units (RTUs) can indeed penetrate a rated roof assembly. This is significant because rated roof assemblies are designed to maintain the integrity of fire-resistive barriers, which protect against the spread of fire and must comply with specific codes and standards. When ductwork penetrates these assemblies, careful consideration must be given to how those penetrations are sealed and protected to ensure that the fire-resistance rating is preserved.

Properly managing these penetrations is essential to maintain the safety and functionality of the building. Neglecting this can lead to violations of building codes and compromises in life safety, ultimately affecting the building's overall performance in emergency situations. When ductwork runs through a rated assembly, additional measures such as fire dampers and appropriate sealing methods become necessary to comply with building regulations and ensure the safety features of the building remain intact.

The other choices, while relevant to the overall discussion of ductwork and installation practices, do not capture the specific critical concern regarding fire-resistance ratings and the implications of penetrating rated structures.