What is the advantage of using double wall pipe?

The advantage of using double wall pipe primarily lies in its ability to provide better draft temperature regulation. Double wall pipes offer insulation between the inner and outer layers, helping to maintain consistent temperatures within the system. This insulation minimizes heat loss, which is crucial for ensuring that the flue gases remain at an optimal temperature for efficient drafting. This means that the exhaust gases can vent effectively, reducing the risk of condensation, which can lead to corrosion and other long-term issues within the piping system.

While the other options present valid aspects to consider in pipe systems, they do not highlight the specific benefits that double wall pipe offers in terms of temperature management and efficiency in drafting.