By far the most popular type of rigid air duct material used in today's homes is sheet metal, which generally refers to galvanized steel or metallic aluminum. Sheet metal is renowned for its durability, protection from dirt and dust, and ease of cleaning and maintenance. The sheet is made of galvanized steel or aluminum, which is hard and thick and known for its smooth surface. Galvanized steel is the most common material used in the manufacture of ducts, as it expands and contracts as it heats up and cools.
Other duct materials include rubber, stainless steel, polyurethane, silicone, PVC, and neoprene-coated polyester fabric. For commercial buildings in extreme climates, the best flexible air filter ducts are made of silicone, PVC, rubber, and stainless steel. These materials have built-in heat and cooling resistance that ensures long-lasting productivity.
Sheet metalducts are the most common type due to their numerous benefits.
A talented sheet metal company can create custom sheet metal ducts that fit any space, including square, round, and decorative shapes. Despite their supposed flexibility, the more curves and folds there are in flexible air ducts, the less efficient they end up being. Wood fiber air ducts can be manufactured on-site to fit any nook and cranny. However, a major drawback is that they are usually quite noisy when the air conditioning system is working; this means that these types of ducts may not be the best option for a bedroom, but they are ideal for living rooms or other open spaces.
Square air ducts fit on walls and above ceilings but use more metal than round ducts to produce the same airflow. You must ensure that the air ducts are always in good condition, as they help to provide thermal comfort and good indoor air quality. Inside, the air duct is sealed to prevent fiberglass fibers and particles from entering the air. Wood fiber ducts are usually covered by a thin layer of plastic to prevent them from being exposed to the weather.
To learn more about air ducts and their materials, it's best to consult an experienced air conditioning repair professional.