What is black mould and how to get rid of it?

If you’re worried you may have a patch of black mould growing in your home, don’t panic. Here’s everything you need to know about identifying it and removing it from your house for good.

Abbie Laughton-Coles
Abbie Laughton-Coles
Updated 18 October 2022  | 4 mins read

Key points

  • Black mould can appear in buildings that have damp issues
  • Bathrooms, kitchens and basements, which tend to be humid with poor air circulation, can provide the right conditions for this type of mould to grow
  • It can usually be removed with mouldicide or fungicidal cleaning products - just be sure to wear protective clothing

What is black mould and what causes it?

Black mould is the common name of a fungus called stachybotrys chartarum. It can be dark green, brown, grey, or black and tends to appear in water-damaged buildings where conditions are damp. It can be especially prevalent in areas with poor air circulation, like bathrooms and basements. You should also look out for it behind furniture that’s pushed against the wall and in the corners of your rooms.

It’s caused by moisture in the air settling on surfaces where spores are able to start growing. When it’s active, it will have a slimy texture.

Humid areas of your home can be a breeding ground for black mould. For instance, having a hot shower and not opening a window, condensation collecting on a windowsill when you have the heating on, or having a steamy kitchen while you’re cooking.

Is it dangerous?

Apart from not being very aesthetically pleasing, black mould can seriously affect your health.

If you have an existing respiratory condition, like asthma or cystic fibrosis, black mould can exacerbate your symptoms.

Once it starts to grow and releases spores into the air, it can trigger asthma attacks and the longer you have exposure to it, the worse it can get.

You should be extra vigilant if there are infants or children living in the property and precautions should be taken if elderly or pregnant people are present, too. Basically, anyone with a weakened immune system needs to be careful around black mould.

Mycotoxins produced by black mould can cause symptoms including:

  • Sneezing, coughing and a sore throat
  • Breathing difficulties
  • Depression and fatigue
  • Continuous headaches

How can I check for mould?

To identify whether you have black mould in your home, you should check for:

  • A musty smell
  • Water damage on your walls, floors or ceiling. You may need to move furniture to assess whether it’s growing behind it, or peel back wallpaper
  • Discolouration on surfaces within your home
  • Any individuals living at the property having breathing problems or developing a cough

Once you’ve found the black mould, you can have it removed and see if the issues subside.

How to remove mould from your home

If it’s a persistent problem, you may need to seek professional treatment. This could include removal of the mould with strong cleaning products, as well as installing a ventilation unit in your property to circulate fresh air throughout the whole home. This should stop any regrowth and improve the quality of the air.

You should be able to remove smaller areas of mould yourself using a fungicidal or mouldicide wash. Just make sure you follow the instructions on the packaging and wear protective gear, like goggles, a mask and gloves, when doing the removal.

Note that using domestic soap and cleaning sprays won’t effectively remove the mould and it may return quickly.

After you’ve removed the mould, you may want to use an anti-condensation treatment, like anti-mould emulsion, which contains biocides to prevent fungus growth. You can also get anti-condensation coating for pipework and ceilings. It works by absorbing moisture, so condensation doesn’t become a problem. If paint isn’t your thing, you can even get anti-condensation wallpaper for walls and ceilings.

How to prevent mould growth in your home

Before removing the mould, you should investigate the suspected cause and take steps to stop it growing, and/or coming back once you’ve removed it.

This may include:

  • Using an extractor fan while you’re cooking on the hob
  • Drying your clothes outside or in a well-ventilated room indoors
  • Ventilating your home adequately by opening doors and windows, even in the winter
  • Avoiding having really hot showers and making sure you have the extractor fan on or windows open

This should help stop moisture building up in your home, so the black mould won’t have the right conditions to grow.

Does home insurance cover black mould?

It will depend on the policy, so read the terms and conditions carefully.

However, you usually won’t be covered for black mould removal and treatment as it’s typically caused by humidity and condensation in a property. This could be due to poor ventilation or damaged pipes and plumbing, which wouldn’t be covered by home insurance.

If the black mould is the result of an insured event, for instance, if a pipe was damaged during a burglary which led to damp in your home, you may be able to claim. The insurer will require evidence that it was caused by the burglary, rather than poor maintenance though.