Rigid ducts are durable and are usually used for which part of the system?

Rigid ducts are durable and are usually used for which part of the system?

• A. Main trunk ductwork
• B. Only attic ventilation
• C. Noise reduction only
• D. Outdoor exhaust

Answer: (A)

Rigid ducts are used for main trunk ductwork because those long, primary air paths need to stay straight, sealed, and durable to move conditioned air from the furnace through the entire system. Their rigid metal construction holds its shape, resists crushing, and provides a smooth interior that minimizes friction and leaks, which helps maintain consistent airflow and static pressure along the trunk line. Attic ventilation or outdoor exhaust often involves routing through tight spaces or around obstacles where flexibility is more practical, and many performance considerations like insulation, noise, and routing come into play beyond just rigidity.

Rigid ducts are used for main trunk ductwork because those long, primary air paths need to stay straight, sealed, and durable to move conditioned air from the furnace through the entire system. Their rigid metal construction holds its shape, resists crushing, and provides a smooth interior that minimizes friction and leaks, which helps maintain consistent airflow and static pressure along the trunk line. Attic ventilation or outdoor exhaust often involves routing through tight spaces or around obstacles where flexibility is more practical, and many performance considerations like insulation, noise, and routing come into play beyond just rigidity.