Black mould on walls


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Have you discovered black mould on your walls? This is a very common problem especially in homes with high humidity levels, condensation problems and poor ventilation. Whether you are a homeowner, landlord or a tenant here is what you should know about black mould growing on walls...

What is causing black mould to grow on my walls?

Generally speaking, black mould needs a lot of moisture before it can germinate and grow. It may come as a surprise just how much moisture comes from everyday chores. Ironing, cooking, showering, washing and drying clothes are all sources of moisture for black mould. Find out more about the causes on our black mould homepage.

Black mould

Stop feeding water to the black mould on your wall

There are typically four main sources of moisture that cause black mould to grow on walls. Cutting off the supply of this moisture is the key to eradicating the issue.

1. Condensation through everyday living

Did you know an average five person household adds 5.5 litres of moisture to their property atmosphere every day? This can lead to an excessive moisture issue within the property in the form of condensation. More often than not, condensation is the cause of black mould growth on your walls.

2. Leaking water in your property

Black mould on walls can spread very quickly if your property has any water leaking as a result of a building or plumbing issue. Any leakage usually occurs under floor boards or behind walls, making it a great moisture source for black mould growing on walls.

3. High humidity levels

It can be difficult to properly ventilate your property. Our Scottish weather is partly to blame. It leads people into closing all their windows and turning the heating up. A classic mistake and exactly what the black mould on your wall wants you to do to help it thrive.

4. Other Damp related issues

Sometimes the presence of black mould may be a tell tale sign to another underlying damp issue such as  penetrating damp. Generally speaking, the mould will be localised to a specific position on the wall if something other than condensation is the cause. 

Black mould loves your bathroom and kitchen walls

The most common walls affected by black mould are ones exposed to excessive condensation, typically your bathroom and kitchen. 

Bathroom walls are often susceptible to black mould growth. Wet surfaces and steam from the shower can cause condensation to form if the bathroom is not properly ventilated.

Common signs of a black mould problem in the bathroom are black spots around the bath seal and between the tiles.
Our Wise tip would be to wipe wet floors and keep a window open during showering. This will reduce the moisture and condensation levels.

Kitchens walls are also a hot spot for black mould due to high humidity levels caused by cooking and washing.
You will most commonly find black mould around the corners of windows and behind kitchen appliances.

Our Wise tip would be to cover pots and pans during cooking. Where possible, keep a window open to properly ventilate the kitchen.

Kitchen and Bathroom ventilation

Concerned about black mould behind walls?

We receive a lot of questions from concerned landlords and tenants worrying about black mould growing behind their walls. The space behind walls tends to be a favourite hiding place for black mould. However, it still needs a source of moisture.  

The appearance of your paint or wall paper can usually indicate a problem.  If it is peeling, cracked or is starting to lose its colour then moisture is almost certainly present. A closer inspection may reveal some black mould growth.  This can sometimes be an indication of a larger black mould problem growing behind the wall. In this instance we would recommend getting a professional surveyor out to identify the extent of the problem.

More about Wise Property Surveys

Removing and preventing black mould on walls

Removing the black mould from the walls is a relatively easy task. Our cost-effective mould control kit comes boxed with everything you need to effectively remove black mould.  However, this is a short term solution to your black mould problem.  

You can only prevent the re-growth of mould on your walls by cutting off its main moisture supply.  In our experience, this is usually the condensation levels and poor ventilation within the property.

Wise Condensation Shop

Find all the DIY treatments you will need to combat black mould. Mould killing spray, anti-condensation paints, dehumidifiers and more...

Condensation shop

Air Ventilation

Air ventilation is the only permanent solution to condensation. If your proerty can "breathe" properly then it can be mould free for good.

Air ventilation

Contact the Black mould experts

If you feel you have a black mould problem that requires professional help, call Wise Property Care on 0800 65 22 678 to speak to our expert team, or click the button below to organise a survey online.

Request a property survey


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