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Does Mold Smell Sweet? (All You Need to Know)

Molds are very common and they can be easily found near us. However, sometimes they hide in the basements, walls, air vents, crawl spaces and other hard to find places and as a result, we can’t detect them easily. 

But the quicker way to check for mold is to rely on your olfactory senses because the most useful weapon for early mold detection is your sense of smell.

Does mold smell sweet?

Some species of mold emit starchy or sickly sweet odors. Actually they release some gaseous compounds and chemical molecules as a consequence of their fungus metabolism that are responsible for that kind of smell. When molds begin to sporulate, the sickly sweet odor becomes stronger.

Depending on their variety, different molds have various smells. Some have a muddy odor, while others have a pungent odor, particularly the black mold, which has a sickly sweet smell. 

Molds have different smells because they release gaseous compounds that cause unpleasant, muddy, or sickly sweet odors. 

Some chemical molecules, such as aldehydes, ketones, estars, lactones etc. are excreted in the air as a consequence of fungus metabolism which causes the starchy or sickly sweet odors emitted by some species. But mostly the aldehydes are responsible for that kind of odor. 

These earthy or sickly odors are also used to identify different mold species. 

Black house mold: 

Sickly smells are one of the signs of stachybotrys black house mold, which is commonly found in damp areas with high moisture content. 

Some may notice black spots with a distinct sickly sweet odor produced by the off-gassing of these molds as they feed and reproduce in these regions. 

When they begin to grow, they release materials such as aldehydes, which provide a sweet odor when their organic molecules decompose throughout metabolism.


These molds have a softer musty odor that differs from the other molds and is commonly compared to damp socks. These molds don’t have as strong an odor as other molds, so they’re easy to distinguish. 

These are commonly characterized by a light gray or yellow tinge on the surface areas as well as a musty, unpleasant, stale, and damp odor that spreads through the air and are mostly found in basements or kits.

What kind of mold has a sweet smell?

Mostly the toxic or fatal molds like black molds (Stachybotrys chartarum) contain a sweet smell. These particular species of molds release gaseous compounds as byproducts of fungal metabolism in the air that cause the sweet, musty kind of smell. 

Though they are not poisonous, they are toxigenic because their spores affect the lungs and cause respiratory problems. They can cause allergies and severe illness to the children and weaker people.

What does mold smell like and where to find them?

Molds have a horrible stinky, musty, stale odor that smells like rotten wood. Their diversity and stage of development have an impact on the smells they produce. 

Some molds emit distinct odors as a result of the production of microbial volatile chemicals at various phases of their development rate. Some molds have strong earthy smells, while others, such as black molds, have sickly sweet odors. 

The production of stinky scents is usually related to the decomposition of organic molecules and their release into the air.

In a house or apartment: 

Molds can be found growing in any unused rooms, kitchen and bathroom corners due to their high sensitivity to moisture. Molds require water to grow. Aside from that, any favorable conditions for their spores, such as dark, moist environments or stagnant air, is an easy excess. 

They usually fall on walls, basements, clothes, cupboards, and edibles and begin to decompose or digest the contents in order to survive.

In walls: 

Moisture is trapped by a peeling, cracked wall or runny ceiling, and fungus thrives in these conditions. They’re grown in a cluster of tiny dots. Molds inside the walls are a symptom of moisture intrusion, and they appear as weak, flaky walls.

In clothes: 

Mold can grow on clothes, especially when they are damp, and cause stains, black spots, and foul odors. Some molds land on cotton fabrics and are able to engulf the organic element.

In carpets: 

Carpets, particularly carpeting in basements, have a significant risk of mold formation because they are regularly wet, and the high humidity encourages mold growth, resulting in stains and odors on the carpet.

In the basement: 

Molds thrive in basements due to a lack of ventilation and higher humidity, so molds seek out these conditions and begin to proliferate.

In air vents: 

Molds can also grow in air vents since they collect a lot of dust on a daily basis and water droplets form during humidification, making them an excellent environment for mold growth.

In the bathroom: 

Bathrooms are the best places for mold to grow. Bathrooms contain a constant supply of water, and mold spores mostly thrive in wet environments. 

In ac: 

Mold grows easily in air conditioners, and the stand-alone units are prime locations for their growth because they are frequently exposed to hot temperatures, in addition to the dark, damp conditions for sporing. 

In the winter, when air conditioners are installed in heated closets, this encourages mold to grow.

How to get rid of mold smell in the house?

Mold can grow in any part of your house and do a lot of harm. They emit microbial volatile organic compounds that produce a low sweet, musty kind of smell. So, you need to take effective measures to get rid of them as early as possible. 

But at first you need to identify the places where they grew up all around the house and necessary steps because only getting rid from the smell will be a temporary solution. 

The obvious places of mold are under the sink, around the toilet, around the kitchen, inside your microwave and stove, between the windows, furniture or fireplace or in the trash. 

Molds grow where they can absorb a lot of moisture, so if you need to fix any water leaks and other moisture problems in your house or you will find yourself right back at square one. After identifying places and fixing the water leaks try these methods to get rid of the moldy smell:

Essential oils: 

Tea tree, clove, eucalyptus, geranium, lemongrass, peppermint etc. essential oils contain volatile chemical compounds and anti-fungal properties that can perish both mold spores and its odor. You can use them as a spray mixing with warm water.

Baking soda and vinegar: 

Make a spray by adding two tablespoons of vinegar, one teaspoon of baking soda and warm water. These are the potent ingredients for eliminating fungus and their stubborn smells.


Borax is known as a potent mold slayer and neutralizer of its smell that’s been used for thousands of years. Take three-four cups of warm water then add half tablespoon of borax and spray it all over the house.

What else would cause a sweet smell in the house?

Most of the time, the reason behind the sweet smell indicates mold and mildew build-ups in your house but without mold, there can be other reasons as well that are responsible for the smell like:

Air Conditioning leakage: 

The air conditioning coolant may leak because of coil leakage and causes a sweet and maple syrup-like smell. When the formic acids from different elements react with  the copper from your air conditioning coils, it causes coil leakage.

Insect infestation: 

Another common cause of a sweet smell can be insect infestation in house by larger bugs such as ants, cockroaches, and bedbugs. 

According to a report from the University of Florida, the bugs or insects can emit sweet oil which actually causes the sweet rotten smell, or a sweet sticky smell. 

Furnace leakage: 

The heat exchanger in the furnace pushes hot air from the furnace through the air ducts but if carbon monoxide leaks from your heat exchanger, it can cause a pleasant sweet smell. It can be hazardous and needs to be solved immediately.

Refrigerant leakage: 

Sometimes, the refrigerator can leak its refrigerant liquids which contain high toxic elements and cause an unusual and sweet smell in your house. This leakage needs to be solved as early as possible or it might cause dangerous medical issues.

Lack of air circulation: 

If your house doesn’t get enough ventilation and air circulation, it can also cause the sweet smell. Open the windows of your house and let the light and air come for a few days which will remove the smell. 

Final thoughts

There are varieties of molds that emit different kinds of smell and depending on the type of smell, they are detected. Molds release gaseous compounds in the air as the byproducts of fungal metabolism but the certain species of mold that release chemical compound aldehydes, cause the sweet smell.