What aspect of duct material affects airflow resistance?

The aspect of duct material that significantly affects airflow resistance is surface roughness. This is due to how the texture of the duct's interior can create turbulence and friction as the air moves through it. A smoother surface allows for a more laminar flow, reducing resistance and enabling better airflow efficiency. Conversely, a rougher surface produces more drag on the air, which can lead to increased resistance and potentially compromise system performance.

Thickness, weight, and length of the duct do play roles in the overall Ductwork design and structural integrity, but they do not directly influence the airflow characteristics like surface roughness does. For instance, thick or heavy materials can be more rigid and durable, but they do not inherently determine how smoothly air flows through or how much resistance it encounters due to friction. Length may affect pressure loss, but it is the roughness of the duct's surface that most critically impacts the airflow resistance experienced.