How to Fix a Slumping Couch

Take off the cushions to figure out exactly why the couch is slumping. If the problem is a broken platform or springs, pressing down on the seat will result in your body sinking down heavily; the springs won’t bounce back as they should or the platform won’t be able to hold your weight. To see if the problem is seat cushions that need replacing or fixing, place them on the floor and sit on them. If they immediately sink down and provide little support and you know your springs and platform are fine, the cushions are your problem.

Measure the length and width of your couch's seat with measuring tape before purchasing anything to fix a slumping seat or busted springs. Otherwise, you may not get the right size product and your couch will still slump.

Buy a product designed to alleviate the problem of a broken platform or springs, such as Sofa Savers or Furniture Fix. You can get it from your local supermarket, discount store, home décor center or through an online retailer. These products can be custom-fitted to the length of your couch, do not require tools and are relatively affordable. They will not fix the problem of sagging cushions.

Purchase a piece of ¼-inch thick plywood the same size as the seat of your couch. Place the wood on top of the seat, then replace the cushions. This solution is best when you do not mind a very firm couch seat or have platform or spring and cushion problems

Use a piece of high-density foam board instead of plywood, if your couch doesn’t slump terribly and you have good cushions. This type of foam board can be bought at craft and hobby supply stores. You may need to buy several pieces, if the store doesn’t sell boards large enough to fit your entire couch seat. Place the foam board on your couch’s seat and put the cushions back on top.

Write down the length and width of each couch cushion, and buy two pieces of high-density, ¼- to ½-inch upholstery foam for each one. The saggier your cushions, the thicker the foam you should get. Furniture repair, upholstery and some hobby shops sell this type of foam.

Unzip your cushions and put one piece of foam on either side of the sagging filling. The foam will enable the cushions to absorb more weight without immediately slumping down.