What's the difference between rigid and flexible duct? A hybrid approach to transitioning to flex duct and the benefit of silence. Risinger gives us an in-depth explanation in this video and tells us which variety he prefers. [Spoiler Alert] It's metal. Why? For starters, they have smoother interiors which results in better air flow, they're more likely to be installed without constriction, it's smooth," and it's not easy to damage when encountered with rodents and UV light. Be sure to ask your HVAX company if they employ this ductwork strategy. Watch now.