Approved liners for a masonry chimney consist of approved aluminum, stainless steel and ______.

Approved liners for a masonry chimney consist of approved aluminum, stainless steel and ______.

• A. listed vent systems
• B. magnesium
• C. black iron
• D. galvanized steel

Answer: (A)

The key idea is that chimney liners must be proven, listed products or specifically approved liners. Aluminum and stainless steel are the two metal options that are commonly accepted, but there’s also a third category: factory-built liners that are “listed” for use as chimney liners. These listed vent systems are manufactured, tested, and labeled for installation inside masonry chimneys, ensuring the liner is designed to handle the heat, vent products safely, and fit with proper clearances. Magnesium isn’t used as a chimney liner because it isn’t a standard, approved material for this application. Black iron and galvanized steel aren’t considered approved liners for masonry chimneys under typical codes either; galvanized coatings can deteriorate with heat and the other materials aren’t listed specifically for lining masonry chimneys. So the best, code-approved third option is listed vent systems.

The key idea is that chimney liners must be proven, listed products or specifically approved liners. Aluminum and stainless steel are the two metal options that are commonly accepted, but there’s also a third category: factory-built liners that are “listed” for use as chimney liners. These listed vent systems are manufactured, tested, and labeled for installation inside masonry chimneys, ensuring the liner is designed to handle the heat, vent products safely, and fit with proper clearances.

Magnesium isn’t used as a chimney liner because it isn’t a standard, approved material for this application. Black iron and galvanized steel aren’t considered approved liners for masonry chimneys under typical codes either; galvanized coatings can deteriorate with heat and the other materials aren’t listed specifically for lining masonry chimneys. So the best, code-approved third option is listed vent systems.