How to Fix a Sagging Couch with Non-Removable Cushions

1 Assess the Damage & Identify the Problem

Start by examining your couch to determine what's causing the sag. Sit on each seat and note where the sagging occurs. Press down on the cushion to feel if the foam has lost its density or if there's a structural issue below. For non-removable cushions, you'll need to work from underneath or through the back of the couch. If you're unsure about the cause, our cushion repair guide offers additional diagnostic tips. Look for these common signs:

• Foam compression: The cushion feels soft and doesn't spring back.
• Broken springs: You feel a hard spot or hear creaking noises when sitting.
• Worn webbing: The fabric straps underneath have stretched or torn.
• Frame damage: The wooden frame beneath may have cracks or splits.

2 Prepare the Area & Access the Cushion

Since non-removable cushions are permanently attached, you'll need to access them through the couch's underside or rear. Carefully turn the couch onto its side or back (with assistance) and locate the dust cover—the black fabric stapled to the bottom. Remove the staples using pliers to expose the inside. If you have a storage couch, you may have easier access through the storage compartment. Once open, you'll be able to assess the internal structure and reach the cushion foam.

3 Replacing or Reinforcing the Cushion Foam

If the foam core is compressed but not completely deteriorated, you can reinforce it without full replacement. Cut a piece of high-density foam to match the cushion's dimensions and insert it beneath the existing foam, resting on the spring deck. This adds support without removing the old foam. For deeper compression, you may need to replace the entire foam core. Measure the cushion carefully and cut the new foam slightly larger (1/2 inch) to ensure a snug fit. For detailed measurements, refer to our measurement guide.

4 Address Spring & Webbing Issues

If the foam is intact but the seat still feels saggy, the springs or webbing may be the culprit. Check the sinuous springs (zigzag springs) for breaks or tension loss. Replace broken springs with new ones of the same gauge. For sagging webbing, you can tighten it by adding additional webbing strips or replacing the worn ones. Use a staple gun to secure new webbing tightly across the frame. This is also a good time to inspect the couch frame for any structural damage that might need fixing.

5 Reassemble & Test Your Repaired Couch

Once you've reinforced the foam and springs, reattach the dust cover using staples. Flip the couch back to its upright position and test each seat. Sit on the repaired areas to ensure they feel firm and supportive. If you notice unevenness, you may need to add additional foam layers. For sectionals, ensure all segments are properly connected. If you have a pull-out sectional, double-check that the bed mechanism still operates smoothly after the repair.