Does Return Duct Need To Be Insulated

Supply air ducts may be left un insulated if they run exposed through the space being conditioned.

Does return duct need to be insulated.

Have to get the air back to the furnace. Typically in residential basement applications they are not insulated. Ductwork insulation prevents condensation. Answered october 21 2019.

Be careful as you choose from the various insulation options. For instance a 2 5 ton system approximately 400 cfm per ton would require 2 14 flexible return ducts or 1 very short flexible 18 duct to move the 1000 cfm required by the 2 5 ton system. If the return duct is subjected to unconditioned air condensation may form and it will need to be insulated. The most applicable repair for duct temperature loss is adding insulation.

Return air ducting is necessary in almost every room. In turn the moisture can lead to all sorts of problems such as mold and mildew growth. Hvac ductwork sizing is critical for proper heating and cooling in every room. Some insulation types offer high promises but fail to consistently perform in the field.

However in recent years u s. Cool air passing through warm areas in your home can cause condensation in the ductwork. Exhaust air ducts normally do not need insulation. These ductwork tips will help balance your air conditioning and heating system.

Un insulated cold air ducts very often have surface temperatures below the local dew point. Then close off that supply and insulate the ducts. Most technicians are skeptical about these numbers especially on the return air side of the system. As you consider adding insulation first be sure the duct system is delivering proper airflow.

If the basement crawlspace is sealed add a return. The school of thought used to be that return ducts only need to be insulated if they pass through an area where the ambient temperature will negatively affect the temperature of the returned air. Insulation prevents condensation and dripping from ducts. Return air ducts only need to be insulated if they pass through environments that adversely affect the return air temperature.

If its not sealed. Department of energy codes ashrae 90 1 2007 and 2010 indicates that returns should in fact be insulated though not usually with the same insulation thickness as the supply.