Duct sealing isn't complicated, it's difficult. If your entire duct system needs to be sealed, it's best to have trained professionals do it for you.  If your duct work needs to be sealed, it's typically in the crawls space and attic, which are difficult spaces to move in and pose threats of inhaling nasty dust and insulation. Proper safety gear should be worn, like a dust mask and Tyvac suit. When you add up the time that it will take to do this work yourself, you might be more interested in paying skilled professionals to do it for you. That's where we come in.