The inner wall of a type "B" vent is typically made from which material?

In the context of venting systems, a type "B" vent is specifically designed for venting gas-fired appliances, such as water heaters and furnaces. The inner wall of a type "B" vent is typically made from aluminum because it is an effective material that provides a balance of durability, corrosion resistance, and thermal expansion, essential for safely conducting flue gases.

Aluminum can withstand the high temperatures and the acidic condensation produced by combustion gases without deteriorating quickly. This characteristic makes it ideal for type "B" venting applications. Additionally, aluminum's lightweight properties and ease of installation contribute to its widespread use in residential venting systems. Other materials, such as stainless steel or copper, are effective in other applications but do not fit the specific requirements for type "B" vents like aluminum does. Plastic, while used in some venting systems, does not provide the necessary temperature resistance for gas venting applications.