Mould around windows is a common issue in many homes, particularly during colder months when condensation builds up. If left untreated, mould can spread quickly and damage surfaces around your home.
In this guide, we’ll explain what causes mould, how to prevent it, and how to remove it safely.
What causes mould in your home?
Condensation is one of the main causes of mould growth indoors. It occurs when warm, moist air comes into contact with colder surfaces such as windows or exterior walls.
Common sources of moisture in the home include:
- Wet or humid weather
- Insufficient heating
- Running taps and sinks
- Baths and showers
- Drying clothes indoors
- Smoking indoors
- Open fires or wood burners
- Everyday activities like breathing and cooking
Without proper ventilation and heating, this moisture can settle on surfaces and create the ideal conditions for mould to grow.
The dangers of mould
Mould is a type of fungus that spreads by releasing tiny airborne spores. It thrives in warm, damp environments, which is why it often appears in bathrooms, around windows, in loft spaces or anywhere moisture lingers.
According to the NHS, exposure to damp and mould can affect health and may worsen respiratory conditions such as asthma.
In some cases, mould exposure may contribute to:
- Asthma symptoms or attacks
- Allergic reactions
- Skin irritation
- Breathing difficulties
Babies, children, older adults and people with existing respiratory conditions may be particularly sensitive to mould exposure.
Can mould damage your home?
Mould doesn’t just affect air quality, it can also cause damage around the home if left untreated.
Common problems caused by mould include:
- Stained walls and ceilings
- Damaged paint or decoration
- Mould spreading to fabrics and clothing
- Damaged furniture
- Softened or weakened floorboards
- Persistent damp patches
Dealing with mould early helps prevent both cosmetic and structural issues from developing.
How to prevent mould
Preventing mould is often easier than removing it. Since condensation is the main cause, improving ventilation and managing moisture levels can make a big difference.
Simple habits can help reduce the likelihood of mould forming in your home:
- Dry clothes outdoors where possible
- Open bathroom windows after showering or bathing
- Keep bathroom doors closed during showers to contain moisture
- Make sure extractor fans are working properly
- Regularly clean carpets and fabrics where dust and spores can settle
- Ensure rooms have good air circulation
- Use anti-mould paint in areas prone to damp
- Consider using a dehumidifier if moisture levels are consistently high
Maintaining adequate heating throughout your home can also help prevent condensation forming on cold surfaces.
Is mould around your windows linked to your radiator?
If mould frequently appears around your windows, insufficient heating could be contributing to the issue.
Windows are often the coldest surface in a room, so moisture in the air naturally condenses there first. If the room isn’t warm enough, that condensation can linger and encourage mould growth.
Ensuring your radiator provides enough heat output (BTUs) for the size of the room helps keep surfaces warmer and reduces the chance of condensation forming.
How to get rid of mould
If mould has already appeared, it’s important to remove it quickly before it spreads further.
Several cleaning solutions can be effective:
Bleach solution
Mix 1 part bleach with 4 parts water if you don’t have specialised mould cleaners.
Anti-bacterial sprays
These can help disinfect surfaces but may not remove stains as effectively as bleach.
Anti-mould sprays
Specialist mould and mildew sprays are designed to remove mould and help prevent regrowth.
Heavy-duty cleaners
Stronger chemical cleaners may be required for stubborn mould, but always follow the instructions carefully.
Steps for removing mould
- Prepare your cleaning solution or anti-mould spray
- Gather a stiff brush, a cloth and a bucket of water
- Consider wearing a mask if you are cleaning a large mould patch
- Apply the cleaning solution to the affected area and slightly beyond the visible mould
- Scrub the surface firmly
- Allow the cleaner to sit for a few minutes if required
- Rinse the area thoroughly
- Dry the surface completely
Drying the area is important to prevent moisture remaining behind.
Extra mould-fighting tips
Different surfaces may need slightly different approaches:
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Around windows: Use a stiff brush to reach into corners and frame gaps
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Walls: A cloth or roller can help spread cleaning solution evenly
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Bathrooms: Check ceilings, grout and window frames where condensation often gathers
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Carpets: Mould in carpets can be difficult to remove and may require professional cleaning
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Paintwork: Use mould-resistant paint in areas prone to condensation
Preventing mould is always easier than removing it. Improving ventilation, managing moisture levels and keeping your home adequately heated can all help reduce condensation and stop mould forming in the first place.
But if mould does appear, acting quickly with the right cleaning methods can stop it spreading and help keep your home healthy and comfortable.
