Not sure how smart this is – but I thought it was pretty clever, and glad that it worked out for them!
pic via
Category: Did You Know?
Folding a Blanket for Storage
Fix a Saggy Sofa with Zip Ties
Use 11″ or better zip ties to tighten up old springs:
First pull off the bottom batting/fabric. Check the springs and make sure there are no broken ones. Start by zip-tying the S springs around the wooden frame (at the top and bottom of each S spring.) Then start on one side and zip-tie diagonally all the way across.
Do It And How 
