Does Return Duct Need To Be Insulated

If its not sealed.

Does return duct need to be insulated.

Cool air passing through warm areas in your home can cause condensation in the ductwork. Condensation will cause a multitude of issues that you definitely want to avoid. If the basement crawlspace is sealed add a return. Hvac ductwork sizing is critical for proper heating and cooling in every room.

Exhaust air ducts normally do not need insulation. Supply air ducts may be left un insulated if they run exposed through the space being conditioned. Be careful as you choose from the various insulation options. These ductwork tips will help balance your air conditioning and heating system.

Insulation prevents condensation and dripping from ducts. Typically in residential basement applications they are not insulated. Un insulated cold air ducts very often have surface temperatures below the local dew point. Some insulation types offer high promises but fail to consistently perform in the field.

This condensation leads to moisture buildup inside the enclosed space of the duct system. However in recent years u s. 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. As you consider adding insulation first be sure the duct system is delivering proper airflow.

Return air ducting is necessary in almost every room. Then close off that supply and insulate the ducts. 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. Return air ducts only need to be insulated if they pass through environments that adversely affect the return air temperature.

If the return duct is subjected to unconditioned air condensation may form and it will need to be insulated. Most technicians are skeptical about these numbers especially on the return air side of the system. Answered october 21 2019. This arrangement also reduces system first cost.

The most applicable repair for duct temperature loss is adding insulation. In turn the moisture can lead to all sorts of problems such as mold and mildew growth.