How to Get Rid of Mold and Mildew: The Complete Guide

Quick answer: To get rid of mold, first fix the moisture that feeds it, then scrub mold off hard surfaces with detergent and water, throw out moldy porous materials like drywall and carpet pad, and dry everything within 24–48 hours. Keep indoor humidity between 30% and 50%. If mold covers more than about 10 square feet, the EPA recommends hiring a professional.

Mold is one of the most common household problems, and one of the most misunderstood. A quick spray of bleach makes it look gone, but it grows back within weeks if the moisture problem stays. The good news: most small mold problems are very fixable with basic tools, if you do the steps in the right order.

This complete guide explains how to get rid of mold and mildew anywhere in your home, what cleaners actually work (and what’s a myth), how to handle each room, and when it’s time to call a pro. Each section links to a detailed guide if you need more.

Mold vs. mildew: what’s the difference?

Mildew is simply mold in an early, surface stage. It usually looks flat and powdery, white, gray or yellow, and sits on the surface of shower grout, window sills or fabric. It wipes off fairly easily.

Mold is the broader term. It can be fuzzy or slimy, often black, green or dark gray, and it grows into porous materials like drywall, wood and ceiling tiles. Both release the musty odor you smell, and both come from the same cause: moisture. The removal method is the same; what changes is whether the material can be cleaned or has to go.

Quick test: dab the spot with a cotton swab dipped in diluted household bleach (1 part bleach to about 16 parts water). If it lightens within a couple of minutes, it’s likely mold or mildew. If it stays dark, it may be dirt or soot.

Wear gloves and eye protection for this test, open a window, and keep kids and pets away. Use bleach only on a hidden spot of a non-porous or paint-safe surface, and never mix it with ammonia, vinegar or other acids.

What causes mold in a house?

Mold spores are everywhere, indoors and out. You can’t remove them all, and you don’t need to. Mold only grows when spores land on a damp surface with something to feed on. According to the EPA, mold can start growing on wet materials within 24 to 48 hours.

The usual culprits:

• High humidity. When indoor relative humidity stays above 60%, surfaces stay damp enough for growth. The EPA recommends 30–50%.
• Condensation. Warm, moist air meets cold windows, exterior walls, pipes and ducts, and water forms. Common in winter on windows and in summer in basements.
• Leaks. Roofs, plumbing, window flashing, washing machine hoses and ice makers.
• Poor ventilation. Bathrooms without exhaust fans, closets on exterior walls, and furniture pushed tight against cold walls.
• Water intrusion. Basements and crawl spaces with poor drainage, and any flooding.

Fixing moisture is the step people skip, and it’s the reason mold comes back.

Can you remove mold yourself? The 10-square-foot rule

The EPA’s guidance is practical: if the moldy area is less than about 10 square feet (roughly a 3 ft by 3 ft patch), you can usually handle it yourself. Larger areas, mold in HVAC systems, mold after sewage or contaminated flood water, and mold in homes where someone has health concerns call for a professional.

Even for small jobs, skip DIY if you have asthma, allergies, a weakened immune system or any breathing problem. Have someone else do it, and talk to your doctor about symptoms. The CDC notes that mold exposure can cause stuffy nose, wheezing and eye or skin irritation in sensitive people.

How to get rid of mold: step by step

This general method works for most small mold problems. Room-specific tips follow below.

1. Protect yourself. Wear an N95 respirator, non-vented goggles and long rubber or nitrile gloves. Wear old clothes you can wash right away. Keep kids and pets out of the area.
2. Find and fix the moisture source. Stop the leak, improve ventilation, or lower the humidity. Check with a hygrometer; if the room is above 60% RH, plan on running a dehumidifier.
3. Contain the area. Close doors, and for larger patches cover doorways with plastic sheeting. Turn off HVAC to the room so spores don’t spread through ducts. A box fan in a window blowing out helps.
4. Lightly mist before disturbing. Mist the moldy surface with water or your cleaning solution so spores don’t go airborne when you scrub. Never dry-brush or dry-sand mold.
5. Scrub hard surfaces. Use detergent and water with a stiff brush or scrub pad on tile, glass, metal, sealed wood, plastic and concrete. Wipe with clean water and dry. Detergent removes mold; it doesn’t have to “kill” it to work.
6. Remove porous materials. Moldy drywall, ceiling tiles, insulation, carpet pad and upholstery that can’t be laundered usually need to be cut out and bagged. Cut drywall at least 12 inches beyond visible growth. Double-bag debris in heavy plastic before carrying it through the house.
7. Dry everything fast. Use fans and a dehumidifier to dry the area completely within 24–48 hours. Wood and drywall should feel dry to the touch and read dry on a moisture meter before you repair or repaint.
8. Clean up the dust. Wipe nearby surfaces with a damp cloth and vacuum with a HEPA vacuum. Launder your clothes and cleaning rags.
9. Check again in one to two weeks. No visible regrowth and no musty smell means you’re done. Regrowth means moisture is still there.

Mold cleanup releases spores and irritants. Wear an N95 respirator, goggles and gloves, keep kids and pets away, and ventilate the room with a window fan blowing outdoors. If you use bleach, dilute it (the EPA and CDC often cite no more than 1 cup of bleach per gallon of water), use it only on non-porous surfaces, and follow the label. Never mix bleach with ammonia, vinegar or other acids, because the fumes are toxic. Don’t use bleach on wood, drywall or fabric, and rinse surfaces between any two products.

Bleach vs. vinegar: what actually kills mold?

This is where most online advice goes wrong. Here’s an honest comparison of common options:

Cleaner	Works best on	Avoid on	What to know
Detergent + water	All hard surfaces	Nothing	EPA’s go-to method. Physically removes mold; rinse and dry well.
Household bleach (diluted)	Tile, glass, sealed countertops, concrete	Wood, drywall, fabric, grout you don’t want lightened	Kills surface mold and removes stains, but doesn’t reach roots in porous materials and adds moisture. Never mix with ammonia or acids.
White vinegar (undiluted)	Hard surfaces, grout, window sills	Natural stone (marble, granite)	Kills many common molds with about an hour of contact. Slower and less effective on some species. Never mix with bleach.
3% hydrogen peroxide	Hard surfaces, some fabrics	Colored fabrics (can lighten)	Leave 10 minutes, then scrub. Less harsh smell than bleach.
EPA-registered mold cleaner	Surfaces listed on the label	Anything not on the label	Follow label contact times exactly. Check EPA registration if you need a disinfectant claim.
Baking soda paste	Light mildew, odors	Heavy growth	Mild abrasive and deodorizer; good follow-up, not a heavy-duty fix.

The bottom line on bleach: the EPA does not recommend bleach as a routine way to clean up mold. On porous materials, it bleaches the surface while the water in the solution soaks in, which can feed regrowth. On hard, non-porous surfaces it works, but so does detergent.

Killing isn’t the goal, removing is. Dead mold can still trigger allergies. That’s why scrubbing, wiping and throwing out damaged materials matter more than which chemical you pick.

How to get rid of mold in every part of the house

Basements

Basements combine cool surfaces, below-grade moisture and lots of stored cardboard, so a musty smell is often the first sign. Dry the space to 45–50% RH with a compressor dehumidifier on a drain hose, clean hard surfaces, and toss moldy boxes. Our step-by-step guide on how to get rid of musty smell in basement walks through it, and our best dehumidifier for basement guide helps you pick the right size.

Crawl spaces

Crawl space mold usually shows up on floor joists and the subfloor, and the smell drifts upstairs. The long-term fix is a vapor barrier, sealed vents and a dehumidifier. Start with how to get rid of humidity in crawl space, then compare units in our best dehumidifier for crawl space picks.

Bathroom ceilings, showers and grout

Bathrooms produce the most moisture per square foot of any room. Scrub ceiling mildew with a detergent solution or 3% hydrogen peroxide on a sponge mop, then repaint with a mildew-resistant bathroom paint once dry. The real fix is ventilation: an exhaust fan sized for the room, run during showers and for at least 20 minutes afterward. See how to get rid of mold on bathroom ceiling for the details.

Closets

Closets on exterior walls stay cool and still, which is why clothes and shoes pick up a musty smell. Leave a gap between clothes and the wall, don’t store damp items, and use a small dehumidifier or a rechargeable desiccant unit. Our guide on how to get rid of mold smell in closet covers it, and our best small dehumidifier roundup explains which compact units actually remove water.

Windows and window sills

Black spots on sills and frames come from condensation that runs down the glass every morning. Wipe sills dry daily in cold weather, clean mold with detergent or vinegar, and lower indoor humidity. More in our guide on how to get rid of condensation on windows.

Walls and drywall

Surface mildew on painted drywall can sometimes be wiped off with a barely damp cloth and detergent. If mold has stained through the paint, the drywall feels soft, or growth returns after cleaning, the paper facing is infected and the section needs replacing. Mold on the inside of exterior walls often signals a leak or missing insulation; find that first.

Clothes, bedding and upholstery

Wash washable fabrics in the hottest water the label allows, with regular detergent, and dry them fully, ideally in sun or a dryer. A cup of white vinegar in the rinse cycle helps with musty odors. Upholstery with visible growth usually needs professional cleaning or replacement, especially if the cushion foam got wet.

Carpet

Surface mildew on carpet that got briefly damp can be cleaned and dried quickly. Carpet and pad that stayed wet for more than 48 hours, or that smells musty from underneath, usually needs to be removed. Carpet over a concrete basement slab is a common repeat offender.

After a flood or major leak

Dry everything within 24–48 hours if you can, remove wet drywall and insulation, and run dehumidifiers and fans. If the water was from sewage, a river or surface flooding, or you can’t dry things fast, call a water damage and mold remediation company. Check with your insurer before you throw things away.

Tools that solve most mold problems

You don’t need a lot of gear. These four tools handle the moisture and air side of most home mold problems. For more options, see our dehumidifier guides and our best air purifier for allergies picks.

Read our full Waykar 80-Pint dehumidifier review for setup tips and how it compares.

An air purifier is a helper, not a fix. It can help reduce airborne spores and allergens while you clean and afterward, but only moisture control and cleaning stop the growth itself.

What about ozone generators and “mold bombs”?

Skip them. The EPA warns that ozone generators should not be used in occupied spaces because ozone irritates the lungs, and ozone at safe levels does little against mold. Foggers and “mold bombs” coat surfaces without removing growth or fixing moisture.

Do I need a mold test?

Usually not. According to the EPA, if you can see or smell mold, you have a moisture problem to fix, and sampling rarely changes the plan. DIY petri-dish kits are unreliable, because spores are present in every home. Testing makes sense mainly when a professional needs to find hidden mold or confirm cleanup after a large remediation.

Mold prevention checklist

• Keep indoor humidity at 30–50% RH, and check it with a hygrometer each season.
• Run bathroom exhaust fans during showers and for 20+ minutes after.
• Use the kitchen range hood when cooking, and vent it outdoors if possible.
• Vent clothes dryers outside and clean the lint path yearly.
• Fix leaks within 24–48 hours and dry wet materials right away.
• Clean gutters, extend downspouts 4–6 feet and keep soil sloping away from the foundation.
• Run a dehumidifier in basements and sealed crawl spaces through humid months.
• Leave a few inches between furniture and exterior walls.
• Store items in plastic bins, not cardboard, in basements and garages.
• Wipe window condensation in winter and consider better window insulation.
• Replace HVAC filters on schedule and keep the condensate drain pan clean.
• Choose mold-resistant drywall and mildew-resistant paint for bathrooms and basements.

When to call a mold professional

Hire a mold remediation professional if the moldy area is larger than about 10 square feet, if mold returns after you’ve cleaned and fixed the moisture, if it’s in your HVAC system or ducts, or if it follows flooding, a sewage backup or contaminated water. Also call a pro if mold is inside walls or ceilings you’d need to open, or if anyone in the home has asthma, allergies, a weakened immune system or symptoms they think are mold-related (and see a doctor). Look for contractors who follow EPA or IICRC remediation guidance and who fix the moisture source, not just the stains.

Mold on the window frame every winter? See our window sill mold guide.

Frequently asked questions

What kills mold permanently?

No cleaner kills mold permanently, because spores are always in the air. What stops mold for good is removing the growth and keeping surfaces dry. Scrub hard surfaces, replace moldy porous materials, fix leaks and hold humidity between 30% and 50%. Without moisture, spores can’t grow again.

Is vinegar or bleach better for mold?

For most homes, undiluted white vinegar or plain detergent is the better first choice. Bleach works on non-porous surfaces like tile and glass, but it doesn’t penetrate porous materials and the EPA doesn’t recommend it for routine mold cleanup. Never mix the two; bleach and vinegar together release toxic chlorine gas.

How do I know if mold is behind my walls?

Warning signs include a persistent musty smell, peeling or bubbling paint, stains that keep coming back, soft or warped drywall, and a history of leaks on the other side. A moisture meter can confirm damp spots. If you suspect hidden mold, a professional can inspect with moisture mapping or a small inspection hole.

Can mold make you sick?

Mold can cause allergy-like symptoms such as stuffy nose, sneezing, coughing, wheezing and itchy eyes in sensitive people, according to the CDC. People with asthma, allergies or weakened immune systems are more at risk. If you have symptoms you think are linked to mold at home, talk to your doctor and fix the moisture problem promptly.

How long does it take for mold to grow after water damage?

The EPA says mold can begin growing on damp materials within 24 to 48 hours. That’s why fast drying matters so much after leaks or spills. Remove standing water, pull up wet rugs, open cavities if needed and run fans and a dehumidifier right away.

Does a dehumidifier get rid of mold?

A dehumidifier doesn’t remove existing mold, but it stops the conditions mold needs to grow and keeps new growth from starting. Clean the mold first, then keep humidity around 45–50% with a properly sized unit. In basements and crawl spaces, this is usually the most important long-term step.

Start with the room that smells worst. For most homes, that’s the basement: follow our guide on how to get rid of musty smell in basement spaces next.