Among the materials tested for chimney construction, which is the least durable?

Wood is considered the least durable material among those tested for chimney construction due to its vulnerability to environmental elements and its inherent properties. Unlike concrete and brick, which are highly resilient to heat, moisture, and weathering over time, wood can deteriorate when exposed to fire and moisture. It is susceptible to rot, insect damage, and warping, which can compromise the structural integrity of a chimney.

Metal, while durable, may be prone to corrosion and rust, especially in climates with high humidity or where salt is used for de-icing. Therefore, wood stands out as the least suitable material for chimney construction due to its lack of resistance to the factors that commonly affect chimneys, such as heat from flue gases and the potential for moisture damage.