What is mould and how to get rid of it?

Find out everything you need to know about mould and causes, treatment and long-term solutions to protect your home.

Home maintenance

14 July 2022

Mould often makes an unwelcome appearance in our homes and while it is relatively common it can also cause harm to your health. That’s why we’ve put together a helpful guide to exactly what mould is, the different mould types to look out for and to how to get rid of mould.

What is mould

Mould is a form of fungus that breaks down dead organic material. It is usually produced in damp and humid conditions. It’s common to notice mould growing in our homes as they offer moisture, warm air, and materials to feed on, such as wallpaper, wood and carpet.

Unfortunately, mould will continue to develop until it’s cleaned and removed and can harm our health, so you must take care when getting rid of it.

What causes mould?

Many of you may be wondering what causes mould on your walls, ceilings, and bathrooms. Getting to the root of the issue is important to know how to tackle it best. Here are some of the common areas mould is found and their causes.


Humidity is one of the most common reasons mould occurs. That’s why mould is primarily found in kitchens and bathrooms where steam often appears from showering and cooking, resulting in more humid conditions than in other rooms.


Condensation is another major cause of mould. Condensation is usually caused when warm air collides with cold surfaces. The moisture in the air cannot escape, resulting in mould. Therefore, you will notice mould on hard and cold surfaces such as tiles or around your windows.

Rising damp

Rising damp may indicate a serious issue in your internal wall. The issues related to rising damp could be due to plumping leaks such as in the water pipes behind your walls or under your shower or bath.

Poor ventilation

Mould will develop without proper ventilation due to the build-up of condensation from everyday activities like drying clothes indoors, cooking, and showering, which can add moisture to the air.

What mould can do to your health

Living in a home where mould is present can affect your physical and mental health. Mould can trigger various health issues such as respiratory infections, worsening asthma, depression, allergic reactions, wheezing, sneezing and coughing. 

It may affect certain groups of people more than others, such as

  • Elderly people
  • Infants and Children 
  • People with existing skin problems, such as eczema
  • People with respiratory problems, such as allergies and asthma
  • People with a weakened immune system, such as those undergoing chemotherapy

It’s important to know what mould can do to your health so you can take precautions, especially for those at higher risk.

Different types of mould to look out for

Mould comes in different forms, some blackish and patchy, others green and textured. Knowing where mould grows in the home can help you stop the issue at its source and prevent you from continually trying to get rid of it.  

Here are some common types of mould in houses and their health implications to look out for.



Alternaria tends to be velvet-like in texture with dark green or brown hairs.

This type of mould tends to be found in damp places such as showers, baths, or under leaky sinks. It grows all year round but is most common between July and September. As it spreads quickly, it’s a good idea to get rid of it as soon as you’ve spotted it.

Health hazards: Alternaria can cause asthma-like symptoms affecting the upper respiratory tract, nose and mouth.



Aureobasidium begins as pink, brown, or black colour and usually turns a darker brown as it ages. It is one of the most common types of mould on walls and can often grow behind wallpaper or on painted or wooden surfaces.

Health hazards: Aureobasidium can cause eye, skin and nail infections and should never be touched with bare skin.



Cladosporium is a greenish-brown coloured mould with a suede-like texture.

It can grow in both cold and warm climates. It is often found in indoor materials, such as upholsteries, fabrics, and carpets, and can grow inside cupboards and under floorboards.

Health hazards: Cladosporium can cause allergic reactions to the eyes, nose, throat and skin and exacerbate asthma symptoms and sinusitis. Due to its potential for causing skin and lung irritation, Cladosporium should never be handled directly.



Penicillium is blue or green with a velvety texture. It can be found on spoiled food and common materials like wood, carpets, wallpapers, and mattresses. It can be found throughout the year, with growth peaking between January and February.

Health hazards: Penicillium spores can become airborne and be inhaled by home occupants, leading to asthma and sinusitis. It can harm those with weakened immune systems as it can worsen their symptoms and result in further health problems.

Black mould (Stachybotrys)

Black mould (Stachybotrys)

What causes black mould? Usually, dark green or black and has a slimy texture that’s easy to mistake for dirt. Humidity and damp conditions are the main culprits of black mould. This type is among the most common type of mould on windowsills as it grows in damp areas with high humidity levels, such as bathroom windows. You will also spot black mould on natural materials such as wood, aluminium wicker, and paper. 

Health hazards: Black mould is generally harmless, but those exposed to a specific strain called Stachybotrys may experience burning sensations in the airways, nose bleeds, fatigue, sinusitis, fever, headaches, and a persistent cough. Stachybotrys are especially dangerous to children, so ensure you remove them from your home when seeking professional help.

How to deal with mould and how to treat it

Your home is somewhere you should feel safe so make sure you know how to keep it free of unpleasant and harmful mould.

Luckily an array of mould and mildew sprays are available. Alternatively, you can also use a natural homemade spray with vinegar and borax 

It is essential to wear protective clothing while dealing with mould, so make sure you’ve got your rubber gloves on, safety goggles ready, and a dusk mask at hand before you start the process.

How to treat mould in specific areas

Whether you’re looking for how to get rid of mould in your bedroom or how to clean mould off your walls, here are some common areas mould is found and how you can treat it. 


Want to know how to get rid of mould in a bathroom? A cleaning solution is an excellent option for smooth bathroom surfaces such as sinks, tiles and bathtubs. Whilst wearing protective gloves, spray a cleaning solution onto the area affected with mould and use a sponge to wipe the mould away. For tighter spaces you can also use a toothbrush for trapped mould.


Mould on kitchen cabinets can be cleaned using a homemade solution with equal parts water and detergent in a spray bottle. Next, use a toothbrush or kitchen scrubbing brush to remove the mould.

Walls and Ceilings

To get rid of mould on walls and ceilings, you will usually need a paint scraper to remove the paint barrier and access the mould to remove it. Once paint or wallpaper is scrapped off, use mould removal spray and a firm sponge to remove the mould.

How to prevent mould from occurring

To stop mould and mildew from ever coming back, it’s essential to get to the root of the cause of the damp in your house and take proper precautions.

  1. Let light enter your home

    Moist and dark spaces are breeding grounds for mould, so ensure your curtains are open during the day to allow natural light and fresh air to enter the room.

  2. Keep air moisture to a minimum

    The key to mould prevention is keeping air moisture to a minimum. Dry any condensation that may be gathering on your walls, ceiling to windowsills. Dehumidifiers can also help to remove moisture from the air.

    Try to keep your bathroom and kitchen door shut tightly and ensure your windows are open whilst cooking.

  3. Cleanliness is key

    Regular cleaning, dusting and hoovering are essential to prevent fungus from growing. Be sure to wash and clean organic materials regularly. Mould and mildew feed on organic materials like wood, cotton, and cardboard.

    Make sure you clean your wooden surfaces, wash fabrics, and replace anything made from cardboard. Remember to change your shower curtains regularly to help eliminate dormant spores and reduce the chances of mould returning.

  4. Ensure your home is well-ventilated

    Ventilation will be your saviour when it comes to tackling damp. If you experience condensation issues often, you’ll need to tackle your home’s humidity.

  5. Say goodbye to mouldy things

    Sometimes saying goodbye to material affected by mould is the best thing to do. Materials such as carpet, drywall and wood must be disposed of if you cannot remove mould.

  6. Keep your home sealed from water

    If mould is caused by water entering your home via damaged or blocked guttering, you’ll need to clear it out, get it repaired or replace it. Ensure that the seals around windows, pipes and doors are in good condition to help keep your home watertight.

  7. Keep your home well-insulated

    During the winter, ensure your home is adequately insulated; that’ll help keep air humidity and condensation levels low and avoid mould from occurring.

  8. Time to call in the professionals

    Mould can often be triggered by damaged brickwork or leaking pipes within your internal walls, which a professional should deal with.

    If your property is suffering from rising damp, it is best to contact an experienced builder to add a damp-proof course. This will ensure a barrier that blocks water from being absorbed from the ground.

    To prevent mould from growing and worsening in your home, it is crucial to recognise and remove fungus as soon as possible. We hope this guide has helped identify the risks and resolutions related to household mould.

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