Symptoms
- Seat cushions dip in the middle
- You feel the frame or springs when sitting
- Cushions don't spring back after standing up
Likely causes
- CommonCompressed or broken-down foamFoam loses resilience after years of regular sitting.
- CommonStretched or torn support webbing/strapsThe webbing under cushions holds their shape and wears out over time.
- PossibleBroken or sagging springsCoil or sinuous springs can lose tension or snap.
- PossibleCushion covers not rotated or fluffed regularlyUneven wear from always sitting in the same spot speeds up sagging.
What to do
- Flip and rotate cushions regularly to distribute wear evenly.
- Remove the cushion and press down on the base to feel for broken springs or torn webbing.
- For fiber-filled cushions, add polyester fiberfill through a small opening to restore loft.
- For foam cushions, order a replacement foam insert cut to the same dimensions.
- If webbing is torn, replace it with new elastic webbing stapled or stretched across the frame.
- Reassemble and check that the seat sits level and firm again.
Tools and parts
- Staple gun
- Scissors
- Measuring tape
Replacement foam cushion insertSearch: “high density foam cushion replacement”
Elastic webbing for furnitureSearch: “sofa support webbing”
When to call a pro
For an antique or expensive upholstered piece, a professional upholsterer can rebuild springs and webbing without damaging the fabric.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.