I know I have leaks in ductwork. House built in 1973, rigid ducts. 1800 sq ft, ranch with ducts in attic. Rather than new ductwork-flex for $3 grand, we are planning on starting at one end of house, removing insulation off ducts, reseal all joints, connections with mastic, reapply insulation wrap on duct and tape with foil tape. Does this sound right. My husband will do the work when temp cools down in attic. I hope to save some money on heat/ac bills. Then we plan to blow in extra insulation. Should we cover the ducts with insulation? Thanks guys for your info. At least I know hubby will not miss any connections.