Your central heating and cooling system uses a network of ducts to distribute heated or cooled air throughout your home. The EPA estimates that on average, about 20 percent of the air moving through these ducts leaks out before reaching your vents. All this lost conditioned air means that your HVAC system must work that much harder to keep your home comfortable.
In addition, if your ducts run through areas that get cold or hot like a basement or attic, insulating the ducts can improve the performance of your HVAC system. Insulating and sealing your ducts can help with uneven heating and cooling problems. The rooms farthest from your air handler are usually the most affected by this problem.
Some ducts are inaccessible because they are concealed behind walls or in ceilings or floors, but if your ducts are accessible in your crawlspace, basement or attic, sealing them properly can save you money on your heating and cooling bills and keep your home more comfortable.
If you choose to tackle the project yourself, use mastic or metal tape to seal any leaking joints in the duct system. Be sure to check around where the ducts connect to the vents and make sure these connections are well sealed. Insulate any ducts you have access to.
A better alternative is to let a reputable local HVAC contractor with experience in air duct fabrication handle the job. They will do a professional job of sealing and insulating your ducts and can identify any other problems with your ductwork such as improper installation and design.
