By Adalheid Voigt. Sofa. At Tuesday, March 05th 2019, 07:49:03 AM.
Before you start, remove your jewelry, especially rings. I almost lost mine in the process! To give yourself room to work on the seat backs, remove all the seat cushions and set them in a clean workspace. Grab a large amount of Poly-fil and begin to shove it up inside the cushion, making sure to position it behind any foam or pillow that may already be in the cushion.
My mom was pretty positive there were no zippers to access the seat backs on her sofa, but after a little spelunking she was very surprised to find that, indeed, there were hidden zippers along the bottom back sides. If you can only get to the seat cushion, skip the Poly-fil and just pick up batting. For seat back access only: just Poly-fil.
Your final product will end up looking really puffy and overstuffed, but the fill will start to settle after a few weeks, so you want to pack it as full as you can. Next, move on to the seat cushions. Remove the cover and set to the side, and vacuum the cushions to get rid of any deteriorating foam.