House smells musty

A weird smell in your house can be caused by something as benign as old food that needs to be thrown away, but it could reveal a dangerous gas leak, fire or pest problem. Here are 10 weird house smells and their … Let’s dive into the causes and solutions to these smelly water issues. 1. My Water Smells Like Sewage. When the aroma of dirt, grime and waste strikes your water supply, the smell can be appalling and insufferable. The sewage smell you’re experiencing can be caused by several factors. It could be the bacteria left by food and soap in your ... Do you find yourself constantly battling with unpleasant odors that seem to linger in your home? Whether it’s the smell of cooking, pets, or general mustiness, dealing with unwante...Dec 6, 2022 · Your house smells musty when your AC is on because there is a buildup of mold in your AC’s system. The commonly affected AC parts are the drip pan, the drain, and the evaporator coil. Often, the drainpipe of your HVAC system might get obstructed, resulting in a damp, musty odor. Damp or musty smell: Mold and mildew. If your nose is picking up something earthy that smells like rotting wood in your house, mold and mildew are probably the ...As a person inhales, air and scent molecules move past the smell receptors in the nose. In turn, the smell receptors relay a signal to the brain. Smells can trigger memories and em...Causes of musty smells in homes. Excess moisture – The presence of water where it shouldn’t be is a leading cause of musty smells in homes. This water can come from a leaky pipe hidden in a …5 Feb 2024 ... Once you've tested your air, it is time to identify the source of moisture. If the musty smell in your home results from mold, finding the ...But, if the house or room smells musty, it will be your cue to get a plumber to fix the pipes. Unfortunately, the smells can be unbearable if your house also has high humidity. So, while the plumbing gets fixed, you should invest in air conditioning products like an air purifier and humidifier to improve the condition.Considerations. If your plant has a musty odor, withhold water until the soil dries out. If the plant still smells, or has visible fungus or mold on the surface of the soil, repot in fresh soil. When repotting, check for slimy or malodorous roots — this is a sign of root rot, and usually means the plant should be discarded, unless most of the ...The musty smell that you may be smelling inside of your home is an odor that is often described as having a stale, moldy, or damp odor – and usually impaired by …Begin learning how to get rid of mildew by scrubbing the area with a 1/2 percent bleach solution. When the area is dry, prime it with an alcohol-based, white pigmented shellac, such as Zinsser Bullseye, and use a paint containing mildewcide. Problem #6. Poorly constructed crawlspaces promote mildew growth.Mar 18, 2023 · How to Get Rid of Musty House Smells When It Rains. When it rains, the air outside is typically fresh and clean. However, when the rain comes into your home, the results can be musty and unpleasant. There are a few things you can do to get rid of musty house smells when it rains. First, make sure that your gutters are clean and free of debris. Step 5. Sweep up the baking soda with a broom, then mop with the water and vinegar cleaning solution. Advertisement. Musty smells, common in many homes, are often found in the flooring of the home. Smell can occur from little ventilation, excess moisture, lack of sunlight or an odor that has developed over the years in older flooring.2 days ago · High humidity creates an environment conducive to mold and mildew growth. By keeping humidity between 30% and 50%, you can discourage the development of musty odors and prevent mold from thriving. Improving Ventilation. Adequate ventilation is key to reducing indoor air pollutants and eliminating stale odors. To remove the musty smell: Clean the evaporator coil, drain pan, or drain pipe. These are the common places where excess water is found and where bacteria and fungi multiply. Wash or replace the AC air filters to remove dust or dirt buildup so that bacteria and fungi will have less to feed on. Seek the services of an HVAC professional …b. Rotten Eggs (Sulfurous), Decayed or Sewage-like Odor. Generally, a rotten egg (or sulfurous), decayed or sewage-like odor in household water is a result of bacterial activity, which can be due to: Bacteria growing in the drain: This is the most common cause of these types of odors. Over time, organic matter such as hair, soap …Use white vinegar to eliminate mold. Absorb odors with baking soda. Dry out the basement with fans or a dehumidifier. Seal or waterproof potential problem areas. To effectively get rid of musty smells in my basement, I start by seeking out the moisture’s origin since this is often where mold and mildew begin.The musty smell in your house you can’t get rid of is likely due to moisture. Excessive moisture can eventually lead to mold, but in many cases, your house will smell musty long before mold grows. You can largely avoid this altogether if you use a dehumidifier to keep your house dry. Keep the humidity range between 40% and 60% to …Open windows, run fans, use dehumidifiers, etc. 2. Clean Carpet. Get a fresh start by vacuuming up debris and dust from the carpet. A simple, thorough vacuuming removes a significant amount of particles and dust from carpet fibers, …Aug 14, 2023 · A clean home is a feast for the eyes. A really clean house smells as neat and wonderfully fresh as it looks—or at the very least, it doesn’t smell at all. While scented cleansers and candles ... My empty house smells musty. If your vacant home has a strong, musty smell, it may be a sign that you have an indoor mould or mildew problem. You should try to locate the source of this smell and isolate it to the room or rooms responsible. Sometimes you may solve the problem by airing out your house or removing a damp dish cloth that lay ...Deodorize the firebox with baking soda. After removing loose soot and ashes from the firebox, sprinkle a box or two baking soda — coating the floor, walls and …Tip 1: Fix Leaks and Broken Plumbing Without excess moisture, a musty smell won’t develop. The main causes of excess moisture in a home include high …Do you think you smell? Well, if we assume for a moment that you actually don’t smell or emit some sort of s Do you think you smell? Well, if we assume for a moment that you actual...Musty Odor. A musty odor isn’t something to take lightly. It typically indicates the presence of mold or mildew, which can damage your home and cause health issues as mold spores circulate throughout your home’s air supply. Common causes of mold include high humidity levels, water leaks, and condensation.For homes that don’t have sealed floors, the exposed earth can produce a musty smell. If the ground is moist, then anything organic in the soil will decay and release smells. Moisture always finds a way to the top, so it might be beneficial to have the crawl space sealed. Make sure crawl spaces don’t use soil or earth from a rural farm.6. Mold and Mildew. While sewer smell is commonly associated with issues in the plumbing system, mold and mildew can also cause a musty smell that can be confused with sewer smell. In homes, damp or humid areas like basements, bathrooms, and laundry rooms can support mold growth and mildew, emitting an unpleasant odor.The house smells like urine after the rain. In most cases, this is caused by a leak in the house facilities or an encapsulated crawl space. In certain situations, pet pee could get soaked up by hardwood and the pee would be squeezed out when there is a rise in humidity. Therefore, you have to deal with the leakage or tear the pee-soaked ...An open box of baking soda can absorb odors in your refrigerator and freezer and anywhere else you want to freshen up. You can also sprinkle a half cup of baking soda in your garbage disposal and ...1. Mildew and Mold in Vents and Air Ducts. The off-putting musty smell may only be noticed when using your AC or heating system. Mildew and mold in vents and air ducts happen when a home is exposed to a high level of moisture in the air, also known as humidity. High humidity and limited ventilation in a home are strong contributing factors that ...2. Scrub hard surfaces with detergent. Scrub non-porous hard surfaces, including walls, the insides of drawers, and laminate, concrete, or tile flooring with detergent and warm water. [2] 3. Cover-up room odors with homemade potpourri. Simmer a stick cinnamon, orange peels, and whole cloves in water on the stove.Clean hard furniture with a vinegar spray (unless the furniture’s finish is delicate). Wash the walls and ceiling with a vinegar and water solution. Mix two cups of …Your house smells musty when your AC is on because there is a buildup of mold in your AC’s system. The commonly affected AC parts are the drip pan, the drain, and the evaporator coil. Often, the drainpipe of your HVAC system might get obstructed, resulting in a damp, musty odor. Also, if water gathers in your drip pan, this is a warning ...b. Rotten Eggs (Sulfurous), Decayed or Sewage-like Odor. Generally, a rotten egg (or sulfurous), decayed or sewage-like odor in household water is a result of bacterial activity, which can be due to: Bacteria growing in the drain: This is the most common cause of these types of odors. Over time, organic matter such as hair, soap …Step 2. Combine equal parts bleach and water in a bucket. Wash the floor and walls of the basement or crawlspace with the solution and a sponge, working from ceiling to floor and making circular motions. Allow the cleansing solution to dry completely to eliminate any remaining odor. This usually takes about 12 to 24 hours depending on the size ...The foul odor can have a number of causes. These can often be traced back to damp problems at home, mould or lack of fresh air. The solution to these three ...If that smell is musty, it may indicate a potential issue that needs to be addressed. Understanding the cause of a musty smell in your house is essential in order to effectively eliminate it and prevent it from recurring. A musty odor is often associated with dampness and mold growth.Musty smells in clothing come from mold and mildew. Wash items with detergent containing enzymes to break down odors. For extra odor-fighting power, add vinegar or lemon juice. Dry completely, as leftover moisture lets smells persist. If odors linger, hang clothes in sun or freeze overnight to kill mold.Method #1: Deep Clean the Closet. The best way to clear up a closet smell is with an old-fashioned deep clean. Start by emptying everything out of your closet. Look for any leaking perfume bottles or other liquids that could be the source of the closet smell. Wipe down the walls and shelves with a vinegar and water solution to dissipate odors.Dec 8, 2023 · Damp, musty smells can happen to even the best-maintained homes. By. Jeff Somers. . Updated on December 8, 2023. Table of Contents. Step 1: Track down the musty smell. Step 2: Get rid of the musty smell. Step 3: Prevent musty smells from coming back. Mould is a common cause of musty smells in areas like basements, bathrooms, closets, attics, and laundry rooms. 3. Another common cause of musty smells in your home is dampness. The walls and floors of your home are covered in a layer of moisture that can be caused by a variety of things including humidity, leaks, and even condensation. 4.Mold and mildew thrive in damp, warm, and moist environments. In most cases, mold spores spread in a house after a water incident – perhaps a burst pipe, a slow leak, or even a bad spill. The longer wet conditions are left untreated, the more the mold can grow and the more toxigenic varieties it attracts.Clean Ducts. It is recommended to clean your air ducts every three to five years so you don’t get a buildup of dirt. If you smell something musty when you turn on your heater, it’s probably because there is a lot of dust and debris. Having a professional come in every few years can keep your ducts clean and improve air ventilation.Apr 5, 2021 · Musty smell in house. A musty, pungent odor could indicate a sink leak or broken pipe that has given rise to mold, which loves to grow in dark, damp spots. “For mold, we’re really concerned ... Feb 15, 2019 · 2. Be a clean freak. Pollutants in the air cling to house dust and smells cling to fabrics, so it makes sense to empty bins more than once a week, to mop up spills and cooking mess after eating and to vacuum once a week with one that has a HEPA filter (the best vacuums for pet hair will do the trick). 3. 1. Wash It. via Today. If you have a smaller item that smells like mildew, the easiest place to start is to wash the item. One item that often smells like mildew is towels. Often towels are left wet and lying around. So you have to deal with the musky mildew smell that just seems to not go away. Your Carpeting Needs Cleaned. There are many reasons why wall-to-wall carpet …For rooms or areas of the house that do not have windows or ventilation fans, bring in electric fans and put them on full speed. #4. Boil Lemon Peels. A quick way to remove musty smells is to boil some water on the stove and add lemon peels to the pot. After the fragrant lemon scent is released, remove the pot from the stove and carefully ...7 Jun 2020 ... Do you leave your air on when you leave? If not, it could just be dust settling. A better filter might help. Also make sure you're consistently ...Cornstarch: Similar to baking soda, create a paste with cornstarch and water. Apply it to the mold, let it dry, and then scrub it off. Tea Tree Oil: In a spray bottle, mix one teaspoon of tea tree oil with one cup of water. Spray on the moldy surface and leave it on for a few hours. Wipe clean with a damp rag.The foul odor can have a number of causes. These can often be traced back to damp problems at home, mould or lack of fresh air. The solution to these three ...The house smells like urine after the rain. In most cases, this is caused by a leak in the house facilities or an encapsulated crawl space. In certain situations, pet pee could get soaked up by hardwood and the pee would be squeezed out when there is a rise in humidity. Therefore, you have to deal with the leakage or tear the pee-soaked ...Dec 27, 2023 · DIY Air Freshener for Musty Smells. 3 cups lukewarm water. 30 drops of any essential oil. Sprayer. tb1234. Shake the water and oils in the sprayer and spritz them into the air or onto your carpet and sofa to disguise the old house smell. Since so many essential oils are available, customize the scent for your room. May 12, 2021 · On the other hand, if the smell is very pungent and consistent, you might be facing a more serious problem. The worst the smell gets, the longer the mold is wreaking havoc in your home and causing long-lasting damage to your health and house. At GreenWorks LLC, mold/mildew is the villain we most often encounter in customer’s homes. Here’s Why. March 8, 2023. Every time your AC comes on, the air leaving your vents stinks with a musty odor. What in the world could it be? Most likely it’s the smell of mold and/or mildew. That’s bad news because your AC is most likely distributing mold and/or mildew spores throughout your home. Both harmful to your health, especially if ...Victorian house smells musty The longer a house has been standing, the longer mould and fungus have had a chance to multiply and dig in. What’s more, Victorian homes and other old structures tend to leave far more openings for damp, are less well insulated than modern builds and, due to their age, are more liable to be peppered with leaks ...To remove the musty smell: Clean the evaporator coil, drain pan, or drain pipe. These are the common places where excess water is found and where bacteria and fungi multiply. Wash or replace the AC air filters to remove dust or dirt buildup so that bacteria and fungi will have less to feed on. Seek the services of an HVAC professional …If the house smells musty after a big rain, you very likely have a moisture problem in the crawl space. The good news is that most smells can be removed if you eliminate the source of the smells. When a big rain occurs, the ground can become saturated and cause standing water to infiltrate the crawl space by penetrating the porous mortar joints ...Why did my perfume smell different when I was pregnant? Find out why your perfume smelled different when you were pregnant Advertisement Many women say they experience a heightened...Mould is a common cause of musty smells in areas like basements, bathrooms, closets, attics, and laundry rooms. 3. Another common cause of musty smells in your home is dampness. The walls and floors of your home are covered in a layer of moisture that can be caused by a variety of things including humidity, leaks, and even condensation. 4.Damp, musty smells can happen to even the best-maintained homes. By. Jeff Somers. . Updated on December 8, 2023. Table of Contents. Step 1: Track down the musty smell. Step 2: Get rid of the musty smell. Step 3: …Locate the source of a particularly bad smell. Mildewy, pet-damaged or stained floorboards, walls, wallpaper and other surfaces are possible sources. Thoroughly clean these surfaces using a hospital-grade botanical (non-allergenic) disinfectant. “Make efforts to replace those compromised materials completely,” Reiner said.Musty odors are generally caused by mold or mildew growing somewhere. Mold and mildew thrive in dark, damp, and warm places. When humidity is high or a material remains damp for more than 24 hours, mold spores are attracted. They collect and emit a sour-smelling hydrogen sulfide gas. Mildew can grow within 24-48 hours in a moist environment ...5 Reasons Your AC Smells Musty & How to Fix It. There are several factors that may cause your air conditioning system to emit a moldy or musty smell. The most likely culprits include the following: 1. Air Ducts or Air Vents Are Holding Excess Moisture. Living in Florida means we deal with our fair share of humidity, which can directly cause ...5 Feb 2024 ... Once you've tested your air, it is time to identify the source of moisture. If the musty smell in your home results from mold, finding the ...2. Poor Air Circulation Inside The House. Inadequate airflow is another common reason a house smells musty, even without mold. When there is stagnant air inside your home, bacteria and other contaminants can get trapped indoors, which results in that old musty smell. This is why having good air circulation indoors is very important.Step three: Cleaning. Next, you should do a detailed clean of everything. Mold can grow on dust, so keeping the home as spotless as possible reduces the number of available nutrients for mold to eat. Removing dust also eliminates another potential source of musty odors. Anything porous should be aggressively aired out outside, and larger items ...Slab with musty smell. New home built 10 mos ago. We are getting a very strong musty potato smell coming from the baseboards on the outer walls and along the supporting walls. The builder did not install drainage tile. They have told us because we are slab on grade it was not required. However we do have a frost wall under. 1. Wash It. via Today. If you have a smaller item that smells like mildew, the easiest place to start is to wash the item. One item that often smells like mildew is towels. Often towels are left wet and lying around. So you have to deal with the musky mildew smell that just seems to not go away. Clean hard furniture with a vinegar spray (unless the furniture’s finish is delicate). Wash the walls and ceiling with a vinegar and water solution. Mix two cups of …Mould is a common cause of musty smells in areas like basements, bathrooms, closets, attics, and laundry rooms. 3. Another common cause of musty smells in your home is dampness. The walls and floors of your home are covered in a layer of moisture that can be caused by a variety of things including humidity, leaks, and even condensation. 4.Heat smells musty in homes for various reasons, including mold in the air ducts, excess dust build-up due to infrequency, and even dirty filters or evaporator coils. While there are multiple causes, fixing the smell will mainly involve cleaning air ducts, eliminating mold, or replacing equipment. In this article, I’ll discuss possible reasons ...Check any pipes that may have a leak. All the toilet valves, sinks, tubs, etc. It's possible one is leaking slowly and causing moisture to get into the walls and sit, which could cause the smell. Keep this in mind, the musty smell is coming from something, it doesn't just happen for no reason, and usually a musty smell is moisture based.There are a few things you can do to get rid of musty house smells when it rains. First, make sure that your gutters are clean and free of debris. This will help prevent water from seeping into your home and causing mold and mildew to grow. Second, open your windows and doors to let in the fresh air.The musty smell in your house you can’t get rid of is likely due to moisture. Excessive moisture can eventually lead to mold, but in many cases, your house will smell musty long before mold grows. You can largely avoid this altogether if you use a dehumidifier to keep your house dry. Keep the humidity range between 40% and 60% to … Pungent, musty odors can make a basement unbearable to spend time in. If strong enough, these awful odors can even work their way up into the rest of the house. Instead of ignoring the problem, learn how to get rid of it. 1. Find the Source. The first step to getting rid of musty smells in your basement is identifying where they’re coming from. Causes of musty smells in homes. Excess moisture – The presence of water where it shouldn’t be is a leading cause of musty smells in homes. This water can come from a leaky pipe hidden in a …3. Open the Windows. Letting some fresh air into the house is not only good at getting rid of the musty stench, but it’s also good for your health. Cracking open a few windows improves your home’s ventilation and prevents the growth of mold.The musty smell in your house you can’t get rid of is likely due to moisture. Excessive moisture can eventually lead to mold, but in many cases, your house will smell musty long before mold grows. You can largely avoid this altogether if you use a dehumidifier to keep your house dry. Keep the humidity range between 40% and 60% to …Mar 1, 2024 · Figuring out why you have a musty smell in your house is the first step to getting rid of it. Mold or mildew is most likely causing the unpleasant odor. People use these terms interchangeably, but they’re actually different. Mold is a fungus that loves to grow in moist, humid places. It’s typically black or green and has a raised, uneven ... 25 Feb 2012 ... Though mold and mildew are not present on the visible interior surfaces, odor-causing microbes may be inside the walls or ceiling. When the home ...If you notice a musty, fishy, or earthy smell in your tap water, it is probably the result of an algae bloom. Algae bloom, or geosmin, occurs when algae grow in a city’s water supply source. Typically algae will be filtered out of the water during the treatment process, but a residual smell often remains behind, and this is what you are ...6) Boil lemon peels, the acidic power of lemon acts as a natural air freshener. Most importantly locate the source, if mould is growing in your home no number of lemon peels or carpet cleaners will eliminate it. Mould fungal colonies can produce gases known as ‘volites’, that cause the musty smells you want to get rid of.Basements have changed a lot over its history in housing—not in structure, but in purpose. While these underground floors used to be relegated to Expert Advice On Improving Your Ho... Let’s dive into the causes and solutions to these smelly water issues. 1. My Water Smells Like Sewage. When the aroma of dirt, grime and waste strikes your water supply, the smell can be appalling and insufferable. The sewage smell you’re experiencing can be caused by several factors. It could be the bacteria left by food and soap in your ... Jul 10, 2023 · To remove the musty smell: Clean the evaporator coil, drain pan, or drain pipe. These are the common places where excess water is found and where bacteria and fungi multiply. Wash or replace the AC air filters to remove dust or dirt buildup so that bacteria and fungi will have less to feed on. Seek the services of an HVAC professional thorough ... mike garten. 9. Sprinkle baking soda on a smelly carpet. Unlike hardwood floors, plush carpets absorb smells like no other. Sprinkle baking soda all over the carpet to remove odors. Let sit (while ...Here we provide you with ten ways to get rid of musty smells in and around the house. 1. White vinegar. Clothes often tend to develop musty smells, either because they are …Mold is a rapidly growing fungus that can be found in your home both on the surfaces where it will taint the color of your walls and will take over your home’s smell. When mold is growing indoors it will produce a gas called microbial volatile organic compounds (MVOC). These gases will emit a musty odor into the environment, which essentially ...Step 5. Sweep up the baking soda with a broom, then mop with the water and vinegar cleaning solution. Advertisement. Musty smells, common in many homes, are often found in the flooring of the home. Smell can occur from little ventilation, excess moisture, lack of sunlight or an odor that has developed over the years in older flooring.8 Possible Reasons Why House Smell Musty. 1. Mold or Mildew Growth. The most apparent cause of musty smells in homes is mold or mildew. Early formation of these fungi may emit a less pungent yet distinct stench. But the longer you leave them to spread in your house, the more pungent the musty odor will be.Musty odors are generally caused by mold or mildew growing somewhere. Mold and mildew thrive in dark, damp, and warm places. When humidity is high or a material remains damp for more than 24 hours, mold spores are attracted. They collect and emit a sour-smelling hydrogen sulfide gas. Mildew can grow within 24-48 hours in a moist environment ...My empty house smells musty. If your vacant home has a strong, musty smell, it may be a sign that you have an indoor mould or mildew problem. You should try to locate the source of this smell and isolate it to the room or rooms responsible. Sometimes you may solve the problem by airing out your house or removing a damp dish cloth that lay ... 10 tips to get musty smells out of your house. Mold and mildew thrive in dark, wet conditions. The key to eliminating a musty aroma and keeping it that way is maintaining proper airflow and humidity levels. There are several ways to do this: 1. Open windows to get rid of stale air and bring fresh air into the space. 2. Air out the home · Invest in a dehumidifier to improve the air and collect moisture · Use essential oils during home cleaning in London · Wash trash cans ...What's that smell? The musty odor on towels, tile, and basement walls can be a sign you have a mildew problem. Don't worry: With a few simple pantry items, you …Wet clothes, damp bags, and soiled carpets can also cause a musty smell. Get quotes from up to 3 pros! Enter a zip below and get matched to top-rated pros near …Wash your filter. Soak your air filters in a solution of part warm water and part vinegar. Let it sit in the solution for around 45 minutes. Use a soft cloth to remove any access dirt. Rinse the AC filter in cold, clean water. Dry your filter. Let the filter dry naturally throughout the day or night.Air conditioner smells can take over the whole house. Your central air conditioner cools down your home’s air and distributes it to every room in the house. So if the indoor part of your system begins to smell musty, that smell will get picked up in your home’s airflow and can stink up every room! But don’t worry, there are some ways you ...Worrying that your house has a bad smell isn’t unusual. In fact, a OnePoll survey from 2022 found that 69% of us fear our house smells when hosting guests. Sometimes, the source of the odor is simply stale air. A lack of ventilation and …The house smells like urine after the rain. In most cases, this is caused by a leak in the house facilities or an encapsulated crawl space. In certain situations, pet pee could get soaked up by hardwood and the pee would be squeezed out when there is a rise in humidity. Therefore, you have to deal with the leakage or tear the pee-soaked ...8 Possible Reasons Why House Smell Musty. 1. Mold or Mildew Growth. The most apparent cause of musty smells in homes is mold or mildew. Early formation of these fungi may emit a less pungent yet distinct stench. But the longer you leave them to spread in your house, the more pungent the musty odor will be.A quick look into your kitchen pantry might reveal one of the most potent natural remedies for absorbing musty smells – baking soda. Placing a bowl of baking soda inside cabinets or musty areas can help combat the smell. For best results, leave it in the cabinet for at least one week.If you live in a humid area, a whole-house dehumidifier will be more effective at keeping the air free of musty odors by removing moisture from the air throughout your house. A whole-house dehumidifier, like this one from AprilAire, connects to an existing forced-air HVAC system and typically uses the same ductwork.Bacteria can form where the concrete slabs have been poured and emit a foul smell. The soil under your house. Dirt can be a source of foul odors if you have a crawl space that is unsealed and has exposed dirt as the flooring. The organic materials that makeup soil decomposes over time, and the natural process of decay invariably …3. Open the Windows. Letting some fresh air into the house is not only good at getting rid of the musty stench, but it’s also good for your health. Cracking open a few windows improves your home’s ventilation and prevents the growth of mold.1. Mildew and Mold in Vents and Air Ducts. The off-putting musty smell may only be noticed when using your AC or heating system. Mildew and mold in vents and air ducts happen when a home is exposed to a high level of moisture in the air, also known as humidity. High humidity and limited ventilation in a home are strong contributing factors that ... | Cujrrecynbgyu (article) | Mbhex.