A musty smell is information. It is rarely a cleaning failure, and it usually cannot be cleaned away, because the smell is a symptom of something damp rather than something dirty.
This is how to find what is producing it, what you can safely clean yourself, and where the honest line sits between a cleaning job and a building problem.
Why does my house smell musty?
A musty smell is almost always moisture: damp somewhere it should not be, feeding microbial growth you probably cannot see. The full answer is in our guide to why a house smells musty, and how to fix it.
How do you find where a bad smell in the house is coming from?
Work by elimination, with your nose near the floor. Close the interior doors, leave the house for an hour, then come back and go room to room. The first breath in each room is the only honest one, because your nose adapts to a smell within about a minute of standing in it.
A short method that works:
- Air the house out completely first — windows open, fans running, an hour or two. Anything that survives that is coming from a source rather than from stale air.
- Go room to room from cold, and write down where it is strongest instead of trusting your memory of it.
- Get low. Musty odors pool near the floor. Kneel at baseboards, inside closets, and at the bottom of cabinets.
- Check the wet appliances — dishwasher filter, washer gasket, refrigerator drip tray, garbage disposal.
- Feel for damp with the back of your hand along baseboards on exterior walls and under every sink. Cool, slightly soft drywall is the finding you are looking for.
- Look behind and underneath rather than at eye level. Mold grows where nobody looks.
If the smell is worst in one room and strongest near the floor, the baseboards are where to look next.
How do you clean mold off baseboards?
Surface mold on painted trim wipes off with detergent and water, but anything that keeps coming back is a moisture problem the cleaning is not going to solve. The full answer is in our guide to how to clean mold off baseboards.
When is a musty smell a job for a remediation contractor?
When the affected area is larger than about ten square feet — roughly a three-foot by three-foot patch — the EPA advises bringing in a professional rather than handling it yourself. The same applies to anything caused by sewage or contaminated water, and to mold you can clearly smell but cannot find.
The EPA's guide to mold, moisture and your home is the practical reference, and two numbers in it are worth keeping. Wet materials dried within twenty-four to forty-eight hours of a leak usually do not grow mold at all. Indoor humidity is best held below sixty percent, and ideally between thirty and fifty.
Happy Maids is a cleaning company, and the limit is worth stating plainly. Mold removal is excluded from our services, along with bodily fluids, pet waste and other biohazards beyond normal bathroom cleaning — that wording is on the policies page. Surface mildew film in a shower is ordinary bathroom cleaning. Mold growing in or behind building materials is remediation work, and any cleaner who tells you otherwise is selling you something.
Do dirty air ducts make a house smell musty?
Usually not, and duct cleaning is oversold as a cure. The EPA does not recommend cleaning ducts routinely, only when there is a specific reason to, and it states plainly that duct cleaning has never been shown to prevent health problems. Chasing a smell into the ductwork is often an expensive detour.
The EPA's guidance on duct cleaning names three situations that do justify it: substantial visible mold growth inside the ducts or on system components, ducts infested with rodents or insects, and ducts so clogged with dust and debris that particles are being blown into the rooms. If none of those describe your house, look elsewhere first.
Before anyone opens the ductwork, change the furnace filter and have the condensate drain on the air conditioner checked. A blocked condensate pan sits full of standing water directly in the airstream, and it smells exactly like a musty basement.
What causes the other common household smells?
Most non-musty household smells come from a short list of places, and nearly all of them are reachable without a contractor. Drains, the dishwasher filter, the garbage disposal, the refrigerator, the trash can itself and the vacuum account for the great majority of them.
- A sewer smell in a rarely used bathroom — the P-trap has dried out. Run the tap for thirty seconds and the water seal comes back. Do the same in floor drains.
- A sour dishwasher — pull and rinse the filter in the base of the tub. It is the most neglected part of a kitchen.
- The garbage disposal — grind ice and a cut lemon, then scrub the underside of the rubber splash guard, which is where the smell actually lives.
- The trash can rather than the bag — wash the body of the can and dry it, since liquid collects underneath the liner.
- The refrigerator — check the drip tray and the drain hole at the back of the interior before blaming the shelves.
- The vacuum — a full bag or a loaded filter turns a vacuum into a machine that redistributes smell. Change it before you clean rather than after.
- The front-loading washer — wipe the door gasket dry and leave the door ajar between loads.
Pet odor in carpet is a different problem. Enzyme cleaners break down the residue that detergent cannot touch, but urine that has soaked into the pad needs a carpet cleaner rather than a house cleaner. Happy Maids does not do carpet or steam cleaning, and saying so is more useful than pretending otherwise. Making a home smell good once the source is gone is its own subject, covered in how to deodorize a house and freshen the air.
Will a professional cleaning get rid of the smell?
It will if the smell comes from something that can be cleaned — grease film, bathroom mildew, a neglected kitchen, a house that has been shut up for months. It will not if the smell comes from moisture inside the structure, from carpet padding, or from cigarette smoke that has soaked into drywall and paint.
A deep clean reaches the places ordinary cleaning skips: baseboards, doors and trim hand-washed rather than dusted, the grease film above the range, the shower worked properly, and inside the microwave. A move-in clean does the same on an empty house, which is where most "this place still smells like the last family" problems are actually solved.
Inside the oven, inside the refrigerator and inside emptied cabinets are add-ons on both services, requested at least one business day ahead — and on a move, nearly everyone takes them. Smells that arrive with fresh construction are their own category, with drywall dust, paint and sealants all off-gassing as they cure, which is what post-remodeling cleaning exists for.
Everything included on each service is written out room by room on the cleaning checklist. If you would rather have a person's judgment on what your house actually needs, call the office at 847-382-0082.
Frequently asked questions
Can you clean baseboards with vinegar?
You can on painted trim, diluted with water, and it works fine on general grime. Keep it off marble, limestone, travertine and unsealed grout, because vinegar is a mild acid and etches those permanently, and keep it off the floor at the base of the trim if that floor is unsealed or waxed wood, or a stone threshold — wipe with a barely damp cloth and dry immediately. For mold, plain detergent and water plus thorough drying does more, since removing the growth matters more than killing it. Never mix vinegar with bleach.
How often should you clean baseboards?
Dust them every time the room is cleaned and wash them properly a few times a year. The full schedule, room by room, is set out in our post on how often you should deep clean your house.
Is a musty smell in the house dangerous?
A musty smell means moisture and microbial growth, and mold affects some people considerably more than others — particularly anyone with asthma or allergies. It is a reason to find the source rather than a reason to panic. If someone in the house has symptoms that track with being at home, that is a conversation for a physician.
Why does my basement smell musty when nothing is wet?
Because humidity alone is enough. Warm, humid air meeting cool basement surfaces raises the moisture at those surfaces, and growth starts without any visible water anywhere. A dehumidifier holding the space below sixty percent relative humidity, ideally between thirty and fifty, usually settles it.
Does Happy Maids remove mold?
No. Mold removal is excluded from our services, along with pet waste, bodily fluids and other biohazards beyond normal bathroom cleaning. Surface mildew film in a shower is ordinary bathroom cleaning and we handle that every visit. Growth in or behind building materials is a remediation contractor's work.
Will an air purifier or a scented candle get rid of a musty smell?
Neither removes the cause. A purifier can reduce airborne particles while it is running, and a candle only adds a second smell on top of the first. Both are worth having once the source is gone. Neither is a substitute for finding it.
My new house smells of paint. How long does that last, and can I wash the walls?
Fresh latex paint keeps releasing as it cures, and curing takes roughly two to four weeks. Ventilate rather than scrub, because washing paint before it has cured burnishes the sheen or lifts it. Happy Maids does not wash walls or ceilings on any service, so this is a ventilation job rather than a cleaning one.