Symptoms
- Persistent musty or stale odor from cushions
- Smell stronger in humid weather
- Odor doesn't go away with normal cleaning
Likely causes
- CommonTrapped moisture in cushion foam or fabricFoam and fabric absorb and hold moisture, which can develop mildew smell.
- CommonMildew or mold growth inside cushionsProlonged dampness, like from a spill or humid storage, can grow mold inside foam.
- PossiblePet odors absorbed into fabric and paddingPet dander and accidents can soak deep into upholstery over time.
- PossibleSmoke or cooking odor absorptionFabric readily absorbs airborne odors from smoking or strong cooking.
What to do
- Remove cushions and covers if possible and air them outside in sunlight and fresh air for several hours.
- Vacuum all surfaces thoroughly, including crevices, using an upholstery attachment.
- Sprinkle baking soda over cushions and fabric, let sit for several hours, then vacuum it off.
- Spot clean with an upholstery-safe fabric cleaner, testing on a hidden area first.
- Run a dehumidifier in the room and improve ventilation to prevent moisture buildup from returning.
- If the smell persists after cleaning and airing out, mildew may be inside the foam and cushions may need replacing.
Tools and parts
- Vacuum with upholstery attachment
- Baking soda
- Upholstery fabric cleaner
Upholstery fabric cleanerSearch: “upholstery odor removing fabric cleaner”
Replacement cushion insertSearch: “replacement foam cushion insert”
When to call a pro
A professional upholstery cleaning service has stronger deodorizing treatments and can assess if mold has developed inside cushions.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.