Get Rid Of Mildew Smell: How To Eliminate And Prevent It

Open a closet, step into the basement, or start a wash cycle—and that stubborn musty, mildew smell hits you. It’s more than an annoying odor; it’s a red flag that moisture has lingered long enough for microbes to grow and release gases that cling to fabrics, carpets, drywall, and even your HVAC. Left alone, smells get worse, allergies can flare, and materials may deteriorate.

The fix isn’t a quick spritz of air freshener. You have to stop the moisture, locate the source, dry things quickly, and clean with the right methods for each surface—without spreading spores or damaging your home. That means smart ventilation, dehumidification, safe cleaners (never mix bleach and ammonia), odor absorbers, proper laundry techniques, and knowing when a hidden problem calls for a certified pro.

In this guide, you’ll get a clear, step‑by‑step plan: find the source, protect yourself, fix leaks, air out correctly, choose effective odor absorbers, clean hard surfaces, rescue clothes and soft goods, address bathrooms and basements, silence a smelly washer, check walls and HVAC, consider advanced tools carefully, build prevention habits, and recognize when to call in expert help.

Step 1. Identify and locate the source of the musty odor

Before you can get rid of mildew smell, you need to find what’s feeding it. Musty odors usually point to moisture hanging around—think bathrooms, basements, laundry rooms, kitchens, or anywhere a leak, spill, or condensation sits. Start with your nose, then your eyes: follow the strongest scent and look for damp spots, discoloration, peeling paint, swollen baseboards, or speckled growth on surfaces and fabrics. If you can’t see it, it may be inside walls, under carpet, or in HVAC components.

• Work the usual suspects: Under sinks, around toilets, tubs, and tile grout; behind appliances; window sills; closets; crawlspaces; basements; and along exterior walls.

• Check laundry hotspots: Washer door gasket and detergent drawer, damp hampers, gym bags, and towels left piled up.

• Move and lift: Pull furniture from walls, lift corner of rugs, inspect padding and subfloor for dampness.

• Use simple tools: A flashlight, a mirror for tight spots, and a basic moisture meter can reveal hidden damp areas.

• Isolate what you find: Bag musty textiles and remove them from the room so the odor trail is easier to follow.

Document locations and severity—you’ll use this map to dry, clean, or remove materials in the next steps.

Step 2. Protect yourself and assess when to skip DIY

Before you try to get rid of mildew smell, protect your lungs, skin, and eyes. Cleaning disturbs spores and fine dust that can irritate airways and spread odors. Suit up, isolate the work area, and set up safe habits so you don’t move contamination into clean rooms.

• Wear protection: Non‑porous gloves, eye protection, long sleeves, and a particulate mask or respirator.

• Isolate the area: Close doors, cover doorways/returns with plastic and tape, and keep kids/pets out.

• Control dust: Mist surfaces lightly before scrubbing, use microfiber and a HEPA‑equipped vacuum where appropriate.

• Vent safely: Use a fan that exhausts air outdoors; avoid blowing air into the rest of the house.

• Use chemicals carefully: Follow labels, ventilate, and never mix bleach with ammonia or other cleaners.

Know when to skip DIY and call a certified pro. Do that if any of the following apply:

• Large or hidden growth: Affected area roughly bigger than a small patch (about a few square feet), or suspected inside walls/HVAC.

• Contaminated water: Sewage/back‑up or floodwater saturation of porous materials.

• Structural/electrical risks: Sagging drywall, soft subfloors, or wet wiring.

• Health concerns: Anyone in the home has asthma, allergies, is immunocompromised, elderly, or an infant.

• Ongoing moisture: Active leaks or chronic humidity you can’t quickly control.

Step 3. Stop the moisture: fix leaks, dry quickly, and dehumidify

Odor control starts with moisture control. Until you stop the water and dry the area, any effort to get rid of mildew smell is temporary. Act fast: eliminate the source, remove what’s wet, and lower humidity so microbes can’t thrive.

• Fix the source now: Shut off water if a pipe is leaking, tighten fittings, replace failed caulk around tubs/sinks, and patch roof or flashing issues. Maintain gutters to route water away from the foundation, and seal gaps at windows/doors to keep damp air out.

• Remove standing water and damp materials: Soak up or extract pooled water. Pull up wet mats/rugs, bag damp towels and textiles, and get them out for separate cleaning or disposal.

• Dry the structure: Run a dehumidifier in the affected rooms to pull moisture from air and surfaces; empty or drain it frequently. Clean or change HVAC filters so the system can move air efficiently while you dry.

• Be weather‑smart: During rainy or humid weather, keep basement and ground‑level windows closed; opening them can add moisture instead of removing it.

• Stay on it: Recheck suspect spots (under sinks, behind appliances, basements/crawlspaces) for fresh dampness and address any new leaks immediately.

Once the source is controlled and surfaces are drying, you’re ready to ventilate without spreading spores.

Step 4. Ventilate and air out without spreading spores

Smart airflow helps you get rid of mildew smell without pushing spores into clean rooms. On dry, low‑humidity days, you can open windows to flush stale air; on rainy or humid days, keep windows closed and rely on dehumidification and targeted exhaust. Your goal is to move damp, musty air out of the house—not through it.

• Exhaust to the outdoors: Place a fan in a window blowing out and crack another window slightly to supply makeup air. Avoid blowing air into hallways or other rooms.

• Use built‑in exhaust fans: Run bathroom and kitchen fans to remove humid air at the source.

• Go gentle over suspect areas: Don’t aim strong airflow directly at dusty or visibly affected surfaces; start with indirect air movement to limit dispersal.

• Add a HEPA air purifier: Run a unit in the affected room to capture airborne spores while you ventilate.

• Support with filtration: Clean or change HVAC filters so your system can move and clean air efficiently while drying.

• Air textiles outside when possible: After washing, hang items outdoors in sunlight to help eliminate lingering musty odors.

Step 5. Use odor absorbers to reduce lingering smells

Once you’ve stopped the moisture and moved air correctly, a faint musty note can still hang around. Odor absorbers trap the musty compounds so rooms reset faster. They don’t replace cleaning or repairs, but they help you get rid of mildew smell while surfaces continue to dry.

• Baking soda: Set shallow bowls of baking soda in the room, closets, or cabinets. For soft surfaces, lightly sprinkle, let sit, then vacuum to lift trapped odors.

• Activated charcoal: Place charcoal bags or bowls of granules in stale areas (closets, basements, under sinks). Swap them out regularly per package directions.

• Household stand‑ins: Bowls of coffee grounds, cornstarch, or unscented kitty litter can neutralize residual musty odors in closed spaces.

• White vinegar (room bowls): Place open bowls of white vinegar in the affected room for several hours to help neutralize lingering smells. Remove and ventilate afterward.

• Commercial odor absorbers: Gel cups or charcoal sachets work well in small spaces like bathrooms, laundry rooms, and mudrooms.

Position absorbers near odor sources (not just the middle of the room), give them time to work, and replace them as they lose effectiveness. Keep bowls and gels out of reach of kids and pets. Next, clean hard, nonporous surfaces so smells don’t return.

Step 6. Clean hard, nonporous surfaces properly (vinegar, peroxide, or diluted bleach—never mix)

Once moisture is under control, scrub away the films and residues that trap odors. To get rid of mildew smell on hard, nonporous surfaces (tile, tubs, sealed counters, glass, metal), use one proven cleaner at a time: white vinegar, 3% hydrogen peroxide, or a diluted bleach solution. Pre‑clean visible grime, keep the area ventilated, follow product labels, and test a small spot first. Never mix chemicals—especially bleach with ammonia or vinegar.

• White vinegar (odor neutralizer): Spray undiluted white vinegar on the surface, let it sit for about an hour, then scrub, wipe, rinse, and dry thoroughly. The vinegar scent fades as it dries.

• Hydrogen peroxide 3% (disinfect/deodorize): Apply 3% hydrogen peroxide, allow a 10‑minute contact time, then scrub, wipe, rinse, and dry.

• Diluted bleach (as labeled): Prepare a diluted bleach solution per the label, wear protection, and ventilate well. Apply, allow the directed contact time, then rinse and dry. Never mix bleach with other cleaners.

Work top‑to‑bottom, use microfiber or non‑scratch pads, and bag disposable wipes. Launder reusable cloths in hot water and dry completely. If odors return, recheck for lingering moisture or hidden sources before repeating.

Step 7. Get mildew smell out of clothes, towels, and linens

Musty textiles hold onto odor compounds, and heat can lock them in. Act quickly and use the right sequence so you truly get rid of mildew smell instead of masking it. Always check garment care tags first and spot‑test anything delicate.

1. Sort and isolate: Keep musty items separate so odors don’t transfer.

2. Pre‑treat with vinegar, then rinse: Mix 1 part white vinegar : 2 parts water, spray or soak 15–30 minutes, then rinse before machine washing. Avoid vinegar on delicate fabrics or elastic; spot‑test.

3. Wash hot (fabric‑safe) with baking soda: Use your regular detergent plus about 1/2 cup baking soda. Choose the hottest water and cycle the care label allows.

4. For stubborn odors: Soak items in an oxygen‑based laundry additive (per label, up to several hours) and rewash. Alternatively, repeat the vinegar pre‑treat (rinse before washing).

5. Dry completely—sun if possible: Line‑dry in sunlight to help neutralize odors, or machine‑dry thoroughly. If odor lingers, rewash before heat sets it.

6. Prevent the comeback: Remove wet loads promptly, leave the washer door/gasket area open to dry, and clean the drum, dispenser, and rubber seal regularly. Avoid pouring vinegar directly into the washer long‑term, as acidity can be hard on components. Store clean textiles in a dry, ventilated area.

Step 8. Treat carpets, rugs, and upholstery (or remove if saturated)

Soft surfaces trap moisture and the VOCs that cause musty odors, so decide quickly whether you can salvage them or need to remove them. If materials are moldy, deeply saturated, or contaminated by dirty flood/backup water, disposal is often the safest route. Otherwise, work methodically to dry, clean, and deodorize without overwetting.

• Start with drying: Extract as much moisture as possible, then run dehumidifiers and gentle air movement until surfaces feel dry to the touch.

• HEPA vacuum first: Use a HEPA‑equipped vacuum to remove fine dust and spores from carpet, rugs, and upholstery.

• Baking soda deodorize: Lightly sprinkle baking soda, let sit several hours, then vacuum to lift trapped odors.

• Spot‑treat stains and odor zones: Use an oxygen‑based carpet/upholstery cleaner per label. For fabric that tolerates it, a light mist of 1 part white vinegar : 2 parts water can neutralize odors—spot‑test first and blot; do not oversaturate.

• Rugs: take them outside: Sunlight helps reduce lingering smells; air on a clean surface and flip to dry both sides.

• Upholstery cushions/covers: Launder removable covers as in Step 7. For non‑removable pieces, clean in small sections and accelerate drying with dehumidification.

• Reassess padding and subfloor: Persistent odor after cleaning often points to musty pad or underlayment; consider removal and professional remediation.

If smells persist or materials stay damp, pause DIY—hidden moisture below the surface needs expert attention before odors will clear for good.

Step 9. Banish bathroom mildew smells at the source

Bathrooms are moisture factories, so musty odors usually mean humidity is lingering on tile, grout, caulk, and textiles. The fix is daily drying plus targeted cleaning. Focus on removing moisture right after showers, scrubbing the biofilm that traps odor, and replacing materials that can’t be salvaged. With the right routine, you’ll get rid of mildew smell and keep it from creeping back.

• Vent right, every time: Run the exhaust fan during showers and 20–30 minutes after; add a dehumidifier in windowless baths.

• Dry daily: Squeegee tile and glass, leave the curtain/liner open to dry, hang towels, and launder mats on a hot, fabric‑safe cycle.

• Clean correctly (pick one): Spray undiluted white vinegar, wait about 60 minutes; or apply 3% hydrogen peroxide for 10 minutes; or use a diluted bleach solution per label. Never mix chemicals.

• Refresh grout and caulk: Scrub clean, let fully dry, then seal grout. Cut out failed or blackened caulk and re‑caulk.

• Declutter and deodorize: Clear under‑sink storage, keep items off damp corners, and place baking soda or activated charcoal under the vanity.

• Replace porous offenders: Swap moldy shower liners, loofahs, and wooden bath mats; clean drain stoppers and fan grilles to remove odor‑holding gunk.

If odors return quickly, recheck for hidden leaks at the toilet base, under the sink, or around the tub/shower valve and fix them before repeating the routine.

Step 10. Tackle basement and crawlspace odors for good

Basement and crawlspace mustiness usually comes from trapped humidity and slow leaks that feed microbial growth on dust, cardboard, fabrics, and old carpet. To truly get rid of mildew smell down there, combine moisture control, smart airflow, surface cleaning, and better storage so odors don’t creep back the next rainy spell.

• Dry the air: Run a dehumidifier to pull moisture from the space; empty or drain it regularly. Use a moisture meter to spot hidden damp areas.

• Fix water entry points: Repair plumbing drips, check water heaters and foundation walls, and keep gutters clear to route rain away. Seal gaps at doors and windows to block humid air.

• Ventilate wisely: On dry days, air out with a window fan exhausting to the outside; keep windows closed during rainy or humid weather.

• Improve airflow and filtration: Keep vents clear, clean/replace furnace or air filters, and consider a HEPA air purifier to reduce airborne spores.

• Ditch odor sponges: Remove old carpet and musty cardboard boxes; opt for hard flooring (tile, vinyl, sealed concrete) and store items in airtight plastic bins.

• Use odor absorbers: Place activated charcoal or baking soda in corners, closets, and under stairs to neutralize lingering smells.

• Insulate and declutter: Proper insulation helps stabilize conditions; fewer dust‑catchers means fewer odor sources.

If odors persist or you suspect growth behind walls or under flooring, pause DIY and bring in a qualified mold/water‑damage professional to inspect and remediate safely.

Step 11. Eliminate washer and laundry room odors

When the laundry room smells musty, the washer is often the culprit: residual detergent, lint, and moisture trapped in the drum, detergent drawer, and rubber door gasket can breed odors. To get rid of mildew smell for good, dry the machine after each use, clean it monthly, and keep the room itself low‑humidity.

• Empty promptly: Don’t let damp loads sit. Move washed items to the dryer or hang‑dry right away.

• Dry the machine: Leave the door/lid and detergent drawer open to air out; wipe the rubber gasket, glass, and drum dry after the last load.

• Clean the gasket and dispenser: Remove hair and residue, then scrub and rinse the rubber seal and detergent drawer.

• Run a clean‑washer cycle monthly: Use the appliance’s cleaning cycle with bleach or a washing machine cleaner tablet; if no cycle exists, run the hottest empty cycle per label directions.

• Ventilate and dehumidify: Run an exhaust fan and/or a dehumidifier so the room actually dries between loads.

• Mind vinegar use: Vinegar can be harsh on washers—don’t pour it in routinely. If you pre‑treat clothes with vinegar, rinse them before putting them in the machine.

If odors persist, recheck for leaks around hoses, valves, or the gasket and address moisture before repeating the cleaning routine.

Step 12. Address odors inside walls, drywall, insulation, and wood framing

When a room still smells musty after surface cleaning, the source may be inside the wall cavity. Drywall, insulation, and dust in stud bays can trap moisture and odor compounds; once contaminated, many porous materials must be removed rather than cleaned to truly get rid of mildew smell.

• Verify and plan: Look for bubbling paint, stains, warped baseboards, or soft drywall. Use a moisture meter. Isolate the area and wear protection.

• Open for inspection: Cut a small low wall section to peek inside. If you find damp, crumbling, or musty drywall/insulation, expand the opening beyond visible staining.

• Remove porous materials: Double‑bag moldy drywall and insulation and dispose of them. BHG advises discarding items that can’t be washed, including insulation and drywall.

• Control airflow and dust: Exhaust air outdoors, not into the home. HEPA vacuum debris and surfaces.

• Clean framing: Wash studs and cavities with detergent first. Then choose one method: apply 3% hydrogen peroxide with 10‑minute contact, or a diluted bleach solution per label, or white vinegar. Never mix chemicals; rinse and dry thoroughly.

• Dry before rebuild: Dehumidify until odors fade and wood is dry to the touch. Fix leaks and moisture entry.

• Rebuild smarter: Consider mold‑resistant drywall and paint to reduce future risk.

If you suspect extensive hidden growth, HVAC involvement, sewage/flood water, or structural damage, bring in a certified mold/water‑damage professional.

Step 13. Check HVAC filters, ducts, and condensate lines

Your HVAC can quietly recirculate musty air or even seed new odor hot spots if dust is loaded with spores or moisture lingers inside the system. To truly get rid of mildew smell, give the system some attention: improve filtration, clear vents, and make sure the air handler isn’t harboring standing water that feeds odors.

• Change/upgrade the filter: Install the highest-rated MERV filter your system is designed to handle and replace it on schedule—more often during heavy use. A clean filter captures more spores and improves airflow.

• Clean registers and returns: HEPA-vacuum grilles and the surrounding drywall, then wipe with a damp microfiber. Keep furniture and drapes from blocking returns so stale air can be pulled out efficiently.

• Look for moisture at the air handler: Check the condensate pan and surrounding area for dampness or pooling water. Standing water breeds odors—if you find any, pause DIY and have an HVAC pro service the drain/line.

• Assess ducts if smells persist: Visible dust buildup or recurring musty odors from multiple vents warrant a professional duct and coil inspection/cleaning and a general HVAC checkup.

• Support with room purification: Run a HEPA air purifier near a central return during cleanup, then replace the HVAC filter after major deodorizing/cleaning work.

A well-filtered, dry, and freely draining HVAC system helps prevent musty air from recirculating and speeds the odor reset across the whole home.

Step 14. Consider advanced odor remediation tools cautiously

If you’ve stopped moisture, cleaned thoroughly, and still catch a stubborn musty note, specialized equipment can help—but treat these as finishing tools, not a shortcut. They work best after leaks are fixed and materials are dry, and they should be used with safety in mind or by a professional.

• HEPA air scrubbers (often with UV): These machines continuously pull room air through high‑efficiency filters (some units add UV) to capture spores and odor‑carrying particles. They’re effective during and after cleanup to reset air quality. Set up in the affected space, seal off doorways, and let them run long enough to exchange the room’s air multiple times. Professional operation is recommended for best results.

• Ozone generators (use only in empty spaces): Ozone can neutralize entrenched odors. However, per common guidance, never run one while people or pets are inside—set it up, leave the area, and air out thoroughly before re‑entry. Ozone treats air and surfaces but does not fix moisture or remove mold growth.

If odors persist after these measures, pause DIY and consult a certified mold/water‑damage pro for targeted remediation.

Step 15. Prevent musty odors with daily, weekly, and seasonal habits

Once you’ve cleared the smell, keeping it gone is about steady moisture control, smart ventilation, and quick cleanups. Build simple routines that dry surfaces and fabrics fast, move stale air out, and stop small leaks before they become big odor problems.

• Daily

  • Vent steam: Run bathroom/kitchen exhaust fans during use and 20–30 minutes after.

  • Dry wet spots: Squeegee showers, spread the curtain/liner to dry, hang towels and bathmats.

  • Handle laundry right away: Don’t let damp loads sit; leave the washer door/detergent drawer open to air out.

  • Stop small leaks fast: Wipe and fix drips under sinks, around toilets, and near appliances.

  • Store smart: Keep clothes dry before putting them away; don’t overcrowd closets or use sealed plastic bags for storage.

• Weekly

  • Wash and fully dry textiles: Towels, mats, and gym gear on fabric‑safe hot settings.

  • Refresh absorbers: Replace or recharge baking soda and activated charcoal in closets, bathrooms, and basements.

  • Check moisture hotspots: Look under sinks, behind washers, and along window sills for dampness.

  • Keep air moving: Clear supply/return vents; wipe gaskets and door seals in washers and fridges.

  • Laundry machine upkeep (monthly): Run a clean‑washer cycle with bleach or a washer cleaner; wipe the rubber gasket and dispenser.

• Seasonal

  • Manage water outside: Clean gutters, ensure downspouts move water away, and seal gaps at doors/windows.

  • Service HVAC: Change filters on schedule, and have a pro check ducts, coils, and the condensate pan/line if you notice recurring musty odors.

  • Declutter and upgrade storage: Remove cardboard in basements; use airtight plastic bins and favor hard flooring over carpet in damp areas.

  • Inspect and reseal: Check bathrooms for failed grout/caulk and repair; look for stains or swelling on drywall and baseboards.

  • Baseline humidity: Use a dehumidifier in basements, crawlspaces, and laundry rooms to keep moisture from creeping back.

Consistent habits make it far easier to get rid of mildew smell—and keep it gone—without constant deep cleans.

Step 16. When to call a certified mold and water damage pro

There’s a point where DIY stalls and you need trained eyes, instruments, and containment to truly get rid of mildew smell. Certified pros can find hidden moisture, prevent cross‑contamination, remove unsalvageable materials, and dry the structure to target levels so odors don’t creep back.

• You can smell it but can’t find it: Persistent musty odor after thorough cleaning/drying, or it returns quickly—often a sign of hidden growth in walls, floors, or HVAC.

• The affected area is sizable or in multiple rooms: Beyond a small patch, or when drywall, insulation, or subfloors show staining, swelling, or softness.

• Contaminated or deep saturation: Sewage/flood water, soaked carpets/pad, or wet insulation/drywall.

• Health or safety risks: Asthma/allergies, immunocompromised occupants, infants/elderly, sagging drywall, warped floors, or any electrical concerns.

• System involvement: Musty air from several vents, dirty condensate pans/lines, or suspected duct contamination.

• You need proper containment/equipment: Negative air, HEPA air scrubbers, controlled removal, moisture mapping with meters/thermal imaging, and structured drying.

A qualified, IICRC‑certified team will isolate the area, run HEPA filtration, remove porous materials that can’t be cleaned, treat and dry framing, and prep for rebuild. In the Austin area, Water Damage Repair Tech offers 24/7 rapid response, free estimates, and certified crews for water, mold, storm damage, and interior demolition to get your home back on track.

Key takeaways

Musty odors are a moisture problem you can solve with a clear sequence. Stop the water, dry fast, clean correctly, and keep air and humidity in check. Do that, and you don’t just mask smells—you remove their source and prevent the comeback.

• Fix moisture first: Find and stop the source before anything else.

• Vent smart: Exhaust to outdoors; dehumidify when weather is humid.

• Clean correctly: One method at a time—vinegar, 3% peroxide, or diluted bleach.

• Launder right: Vinegar pre‑treat (rinse), baking soda, hot cycle, full dry.

• Know what to toss: Porous items that stayed wet are often unsalvageable.

• Maintain airflow systems: HVAC, filters, drains; use absorbers as finishers.

• Call pros when needed: Large, hidden, contaminated, or recurring problems.

If you’re in Austin and need fast, certified help, the team at Water Damage Repair Tech can locate the source, contain it, dry your home, and get the musty smell gone—for good.