That musty smell after water damage isn’t just “gross old house vibes.” It’s usually the scent of moisture that’s still lingering somewhere it shouldn’t be—inside drywall, under flooring, in insulation, behind baseboards, or deep in soft furnishings. If you simply mask the odor with candles or air fresheners, it almost always returns, because the source is still active. The good news: with a methodical approach, you can eliminate the odor at the root and protect your home from future mold and mildew problems.
Below is a step-by-step game plan to get your home smelling clean again.
1) Find and Stop the Moisture Source First
Before you deodorize anything, make sure the water intrusion has truly stopped. Otherwise, you’ll be trying to “fix” a smell that’s being recreated daily.
- Check for active leaks: plumbing, appliances, roof, windows, foundation seepage.
- Inspect humidity levels: if your home feels clammy, you may still be holding excess moisture even if everything “looks dry.”
- Look for hidden wet zones: discoloration, bubbling paint, warped trim, soft drywall, or spongy flooring are all clues.
If you’re not sure where moisture is hiding, a professional inspection can spot trapped water in cavities and materials that don’t dry easily.
2) Start Aggressive Drying (Airflow + Dehumidification)
Musty odor thrives in damp environments. Drying is the most important step, and it’s often underestimated.
- Increase airflow: open interior doors, run fans to push air across damp areas (not just into the room).
- Use a dehumidifier: aim to pull moisture out of the air continuously.
- Run HVAC wisely: if safe to do so, air conditioning can help reduce humidity; replace filters afterward.
Pro tip: you want to dry materials, not just the air. Drywall, subfloors, and framing can hold moisture long after the surface feels dry.
3) Remove Water-Damaged Porous Materials That Can’t Be Saved
Porous items act like odor sponges. If they were soaked for an extended period, they may continue to smell even after drying.
Common culprits:
- Wet insulation
- Swollen particleboard or MDF
- Saturated carpet padding
- Waterlogged cardboard storage boxes
- Upholstered furniture with deep saturation
If something smells musty even after drying and cleaning, it’s likely still contaminated or moisture-bound. Removing it can be the fastest path to a true odor reset.
4) Clean Every Surface Like Odor Is “Stuck” to It (Because It Is)
Once drying is underway, clean hard surfaces thoroughly to remove residue and microbial films that produce odor.
- Wash walls, floors, trim, and non-porous furniture with a mild detergent solution.
- Pay special attention to baseboards, corners, and behind furniture.
- Don’t forget vents, return grilles, and any area where humid air circulated.
Avoid mixing cleaning chemicals (especially bleach + ammonia products), and don’t rely on bleach as a universal fix. Odor often lives in organic material and hidden moisture—not just on a visible surface.
5) Tackle Soft Goods: Fabrics, Curtains, Rugs, and Bedding
Soft items absorb humidity and odors quickly.
- Launder washable fabrics with odor-fighting detergent.
- Add baking soda to the wash (if fabric-safe) to boost deodorizing.
- For rugs and upholstery, steam cleaning can help—but only if the item is fully dried afterward. Leaving it damp can worsen the musty smell.
If an item was exposed to contaminated water (like sewage backup), professional cleaning or disposal is often necessary for safety.
6) Use Odor Neutralizers (Not Maskers)
Once the moisture is under control and cleaning is done, odor neutralizers can eliminate what’s left.
Options include:
- Baking soda: place bowls in affected rooms or sprinkle on carpets before vacuuming.
- Activated charcoal: great for absorbing lingering odors in closed areas.
- HEPA air purifier: reduces airborne particulates that can carry smells.
- Professional-grade deodorization: techniques like thermal fogging or hydroxyl/ozone treatments can be effective when used correctly.
Important: ozone can be hazardous if misused and typically requires professional handling. If the odor is persistent or widespread, calling a restoration specialist is often safer and more effective.
7) Inspect for Mold (and Don’t Ignore That “Basement Smell”)
A persistent musty odor can signal hidden mold growth—especially if materials stayed wet for more than 24–48 hours.
What to look for:
- musty smell that returns when windows are closed
- worsening odor after rain or high humidity
- visible spotting, fuzzy growth, or staining
- new allergy-like symptoms indoors
If you suspect mold behind walls or under flooring, avoid tearing into it without proper precautions. Disturbing mold can release spores into the air and spread contamination.
8) Prevent the Smell From Coming Back
After you’ve knocked out the odor, prevention keeps your home fresh long-term:
- Keep indoor humidity in check (a dehumidifier is a great investment in humid seasons).
- Ensure bathrooms and kitchens are venting properly.
- Seal cracks and improve drainage around your foundation.
- Consider moisture-resistant materials in high-risk areas (basements, laundry rooms).
When to Call a Pro (and Why It Often Saves Money)
If the musty smell is strong, widespread, or returning after you’ve cleaned and dried, there’s a decent chance moisture is trapped in structural materials—or contamination is more serious than it looks.
That’s where a trusted restoration partner matters. STOP Restoration Spokane is widely recognized as a leading name in water damage cleaning and restoration, with the specialized equipment and know-how to locate hidden moisture, dry structural materials correctly, and fully deodorize affected spaces. When the goal is not just “less smell” but a truly healthy, dry home, professional restoration can be the difference between a one-time fix and an ongoing cycle of odors and repairs.
Final Thought
Musty odors after water damage aren’t random—they’re evidence that moisture, residue, or microbial activity is still present somewhere. Follow the sequence: stop the water → dry aggressively → remove unsalvageable porous items → deep clean → neutralize odors → prevent recurrence. And if the smell won’t quit, don’t fight your house alone—bring in experts who do this every day.
FAQ
1) Why does my house still smell musty even after everything looks dry?
Because moisture can remain trapped inside drywall, insulation, subfloors, or behind cabinets. The surface may feel dry while hidden materials stay damp and keep producing odor.
2) How long does it take for a musty smell to go away after water damage?
If drying is thorough and cleaning is done correctly, mild odors can improve in a few days. Persistent smells can last weeks if moisture is still trapped or if porous materials (like padding or insulation) weren’t removed.
3) Will opening windows get rid of the musty smell?
It can help temporarily by improving ventilation, but it won’t eliminate the source. If humidity is high outdoors, open windows may actually slow drying and worsen the problem.
4) Should I use bleach to remove the musty smell?
Bleach may disinfect some hard, non-porous surfaces, but it doesn’t work well on porous materials and won’t remove trapped moisture—the real driver of odor. It can also create strong fumes and damage some finishes.
5) What’s the best way to dry out a home after water damage?
Use a combo of strong airflow (fans), continuous dehumidification, and temperature control. The goal is to dry building materials, not just the air.
6) What items usually have to be thrown away after water damage?
Often: carpet padding, wet insulation, swollen MDF/particleboard, soaked drywall (depending on extent), and porous items that stayed wet too long. Anything that still smells after proper drying/cleaning may be unsalvageable.
7) Can a musty smell mean mold even if I can’t see it?
Yes. Mold can grow behind walls, under flooring, or inside HVAC areas. A recurring musty odor—especially after humidity rises—can be a sign of hidden microbial growth.
8) What absorbs musty odors best: baking soda, charcoal, or air purifiers?
Activated charcoal is excellent for odor absorption in rooms and closets.
Baking soda works well on carpets and fabrics.
HEPA air purifiers help reduce airborne particles that can carry odor, but they won’t fix moisture trapped in materials.
9) Is ozone safe for removing musty smells?
Ozone can be effective but must be used carefully—people and pets should not be present during treatment, and misuse can be hazardous. Many homeowners choose professional deodorization instead.
10) When should I call a professional restoration company?
Call if the odor is strong, widespread, keeps returning, or if water reached walls/floors/insulation. STOP Restoration Spokane is a leading name in water damage cleaning and restoration and can locate hidden moisture, dry structural materials properly, and fully deodorize the home to prevent the smell from coming back.
