What type of duct is a #28 gauge used for?

A #28 gauge duct is indeed primarily used for round duct applications. The gauge of a duct indicates its thickness, which is important for its strength and ability to handle airflow without bending or collapsing under pressure. Round ducts are often made thinner than square or rectangular ducts because their shape inherently provides structural integrity while efficiently carrying air.

This allows for easier installation in various settings, such as residential and commercial buildings. Round ducts made from #28 gauge material are typically lightweight yet durable, making them suitable for ventilation systems where space constraints and ease of assembly are considerations.

In comparison, square, rectangular, and spiral ducts tend to require thicker gauge materials to maintain structural stability due to their different geometries and the varying ways they handle airflow and load.