Upholstery. So to speak: they reattached a piece of batting to the bottom of the sofa.
Ah. That I understand. I had the unenvious task of installing a queen-sized bed in an upstairs bedroom. Headboard, okay; footboard, okay; rails and mattress, okay -- box spring, not so fast.
To get the box spring up the stairs, I had to fold it. This entailed removing the dust cover (and all its staples), sawing the side frames in the middle, foding it in half and then carrying it upstairs.
Then I had to attach bracing boards to the side frames, reattach the dust cover (and all its staples), and then *voila*, one queen sized bed, upstairs. -- Easy-peasy.