How to find and remove musty smells in your house

Mould, mildew, and must are all unpleasant smells that are commonly found in homes.

An earthy smell in the house could be caused by a number of fairly harmless things, from mouldy food in the fridge to wet laundry being left out. However, it could also be a sign of a larger problem, such as a serious damp issue.

If your house smells like mould and the problem is left unchecked, it could become more than just an annoying smell, potentially leading to severe structural damage and even physical health problems. Read on to learn some of the common reasons why your house smells like mildew, the negative effects mould can have, what a musty room means, and some simple tips to eliminate the smell from your home.

Table of Contents

Mould odours: What causes musty odours in your house?

What is mould and why does it smell?

Mould is a structure formed by some types of fungi. It is commonly found on food, such as old fruit, and on surfaces. On surfaces, it usually grows in darkly coloured patches. Mould needs moisture to grow, so it is prevalent in damp, dimly lit areas such as basements, around leaking pipes, and on absorbent surfaces that are exposed to moisture.

Mould produces spores to reproduce, which disperse in the air and can cause detectable smells that you might also describe as “must” or “mildew”.

Effects of mould on your health

The smells created by mould around the home can have a negative effect on your health, causing stress and discomfort. Mould growth can also cause an itchy nose, sore throat, coughing, burning eyes, and rashes, and in severe cases and in susceptible people, allergic responses, breathing problems, and lung infections. Due to the potential health impacts, and the discomfort caused by mouldy smells, it’s important that you identify and eliminate their source in your home.

A photo of a women holding her chest

How to find the source of musty smells

The unique musty odour of mould is caused by volatile organic compounds formed during the growth process. Because of this, a musty smell is an indication that the mould in your house is alive and growing, so it’s important to take action and prevent any further spread.

The first step is to identify the source of the odour. Let’s unpack some of the best places to look.

Rooms with high humidity

Bathrooms

Bathrooms are one of the most common places to find mould and mildew in the home. The main cause is the high level of moisture usually found in bathrooms, with showers, baths, toilets, and sinks being used daily.

To add to the problem, towels, shower curtains, washcloths, and bath mats are often left damp for long periods of time. It’s also often difficult to ventilate the rooms sufficiently, leading to a build-up of humidity and ideal conditions for mould to grow on fabrics and surfaces.

Use water at 50°C or higher over the entire contaminated area to wash off the dirt. Five seconds or more per point is ideal. Once you’ve done this, remove all moisture with a towel or squeegee.

The kitchen

Firstly, there is usually a lot of water in kitchens around the sink and on surfaces due to spills. Secondly, food stored in kitchens can expire and become the perfect place for mould to grow.

If you suspect the mildew smell is coming from your kitchen, try checking for leaks and damp patches, as well as any mouldy food items on the floor, in the fridge, and in the cupboards.

A photo of a minimalistic kitchen

Poorly ventilated rooms and other areas

Mould is more likely to grow in recessed areas where ventilation is poor and humidity tends to accumulate. The simplest solution to this is to open windows and doors in the affected room, but a fan and/or dehumidifier can also be useful.

Closets and storage

Closets and storage spaces are often left unchecked for long periods of time. They’re also dark and can trap moisture if you have any leaks or damp issues in the surrounding walls. All of this creates an ideal good environment for mould to grow, so you should check all storage spaces in your home if you detect an earthy smell in the house.

It’s also good practice to avoid overfilling storage spaces with clothing, as well as adding a fan or similar device to ensure good ventilation.

A photo of a closet full of clothes but well organized.

Doorways and windows

Leaks are common in doorways and windows that open to the outdoors, which can lead to dampness and in turn lead to mould. Entrances to the home are therefore a likely to be a source of damp smells, so try to check around the doorway for signs of mould.

The basement

Basements are underground and surrounded by dirt, with poor ventilation and low levels of natural light (or none whatsoever). This can make them a breeding ground for mould and mildew, especially after wet weather. For example, many people detect a musty smell in the basement after rain.

If you think your basement could have a mould problem, try carefully checking the walls and dingy corners for visible signs of dampness and mould.

Rooms with dust, dirt, or food debris

Dust, dirt, and food debris can feed mould. Mites live in dust, and their droppings and corpses can feed the mould. In addition, stains left after spilling food scraps, seasonings, and soups are rich in nutrients which can further nourish the mould. Because of this, it’s important to keep areas free or dust, and food debris by cleaning frequently.

Living room and dining room

While living rooms and dining rooms may not be the most obvious places to find mildew, it’s worth checking carefully to see if they’re the source of the musty odours in your home. Food and drink are often consumed in living rooms and dining rooms. When combined with soft absorbent surfaces like sofas, carpets, and rugs, moulds can thrive here.

If there’s a mouldy smell that seems to be coming from your dining room or living room, check for food debris and spills, as well as damp patches on the walls.

Bedrooms

Bedrooms are one of the less likely places to find mould growing, but a mould issue where you sleep could put your health at risk, so it’s important to check. To check your bedrooms for mould, look for visible signs on the walls, in corners, and behind furniture. Also try checking your dirty laundry, looking for leaks around the ceiling, pipes, and radiators, and for damp patches on your soft furnishings.

How to get rid of musty smells in your home

A photo of a living room with the doors opened to bring in fresh air

Regular ventilation

Ventilation can remove the musty air that causes a buildup of bad odours. Additionally, it can reduce moisture levels in an affected area, limiting the mould’s ability to grow.

Use an air purifier

Air purifiers are a cost-effective and effortless way to remove moisture, allergens, and mouldy smells from the air in your home. If you have a persistent issue with damp odours, try using an air purifier to eliminate the problem.

Air fresheners

Air fresheners are an easy and cost-effective way to mitigate bad smells in your home. There are several kinds available, from plug-in devices to wicking fresheners, diffusers, and more. Generally, they all work well at covering bad smells.

Baking soda

Along with all its other uses, baking soda is an excellent deodoriser that’s suitable for use in the home. For example, to clean a smelly bin, try adding around 50 grams of baking soda to the bin followed by hot water. Leave it to sit for a few minutes, rinse it out, and the smell should be gone or significantly reduced.

How to eliminate the mould that causes bad odour

Ultimately, the only way to truly eliminate musty smells from your home is to get rid of the mould that’s causing them. Fortunately, there are a few simple steps you can take in order to achieve this.

Eliminate moisture and keep the house dry

Mould can’t live without water, so the number-one way to eliminate a mould problem is to remove as much moisture from the area as possible. Consistent moisture and humidity in the air can cause your home to attract mould growth. To prevent this, try to remove moisture from the air by increasing the amount of ventilation, which you can do by opening windows and using fans. If this isn’t enough, you could try using a dehumidifier in the most problematic rooms to consistently lower the level of moisture in the air.

Deep-clean to remove dust, mould, and mildew

Physically removing patches of mould and mildew can reduce musty odours and health risks. To clean a patch of mould, use a damp cloth to wipe away the visible signs and then dry the area. Also, an antifungal cleaner can kill the mould and prevent it from growing on surfaces. Try to deep-clean high-risk areas like carpets, rugs, showers, sinks, and damp corners regularly. Dust can also cause a mildew odour in the home, so dusting surfaces regularly and cleaning vents/ducts can prevent this smell.

A photo of a wall with mold being cleaned

How nanoe™ X technology in your house can remove mould, mildew, and musty odours

Panasonic nanoe™ X technology creates nano-sized water particles containing hydroxyl radicals, releasing them into the air. These highly reactive particles instantly bind with mould spores in the air, significantly reducing mildew and musty odours.

At Panasonic, we’ve been working on nanoe™ X technology for more than 20 years. In addition to reducing mould smell, nanoe™ X is proven to reduce other bad smells, allergens, pollens, pesticide residues, and PM2.5 pollutants.

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