A TEAM of experts has estimated that black mould could significantly devalue the price of your home by as much as £50k.

A mould, a type of fungus that thrives in dark and damp environments, is not only horrible to look at but can be harmful to our health and homes. 

Homeowners have been warned that black mould is one of the most concerning issues to face when it comes to looking after a property.

With this in mind, expert Alison Graves from Hyperion Tiles, has shared some advice about how to spot the signs of black mould early, when to seek professional help and how much it could cost if you don't fix it quickly.

“Mould is not just a cosmetic issue but a potential health hazard. Early detection and proper remediation are key to protecting your home and health," Alison commented.

She added: "If you notice any signs of black mould or experience unexplained health issues, don’t hesitate to seek professional help. Timely intervention can prevent costly damage and ensure a safe living environment.”

How do you tell if you have black mould?

Alison has shared some of the things that homeowners should be on the lookout for in their houses.

Visible Mould Growth

The pro explained that the most obvious sign of black mould is visible growth.

You'll be able to spot it because it often appears as dark, slimy spots on walls, ceilings, or other surfaces.

She added: "It can be black, dark green, or even dark brown. If you see mould growing in your home, it's a clear indication that there's a moisture problem that needs addressing".

Musty Odours

You can also tell if your house has black mould from its distinctive musty smell, Alison added.

The expert continued: "If you notice a persistent musty odour in certain areas of your home, especially in bathrooms, basements, or areas prone to moisture, it could indicate hidden mould growth".

Water Damage

If you also spot signs of water damage - discoloured walls, peeling paint, or water - this could mean that you also have mould. 

The expert reminds homeowners that mould thrives in damp environments, so any area that has experienced water damage is at risk.

Health Symptoms

The presence of black mould can lead to health issues especially if you or your family have underlying conditions. 

If any of your household experiences unexplained allergic reactions, respiratory problems, headaches, or skin irritation, mould could be the culprit.

The pro urges people to pay attention to symptoms that worsen in or outside the house.

Condensation and Humidity

Alison commented: "Condensation on windows, pipes, or walls, as well as consistently high humidity levels, create ideal conditions for mould growth.

"Use a hygrometer to monitor indoor humidity and keep it below 50% to prevent mould from thriving".

Cracked or Peeling Paint

If you see cracked or peeling paint in your house - especially in areas prone to moisture - this can be a sign of hidden mould growth.

The paint cracks and peels because the mould causes it to lift and bubble.

Warped Walls or Flooring

"Warped or bulging walls and flooring can indicate a serious moisture problem, which can lead to mould growth," the expert warned.

Alison urges that if you notice these signs, you should investigate the source of the moisture immediately.

Does mould devalue a house?

Homeowners are being warned that untreated mould can significantly devalue your home.

The expert estimates that, on average, the presence of mould can reduce a property's value by 20% which can be thousands of pounds.

For instance, if your home is valued at £250,000, untreated mould could decrease its value by as much as £50,000.

The perceived health risks and the costs associated with mould remediation are why black mould affects home valuations since potential buyers have to factor in these costs when considering a purchase.

When do you need a professional to remove mould?

While some mould issues can be handled with DIY solutions, certain situations require professional help 

Alison Graves has rounded up the key scenarios where you should call in the experts.

Large Affected Areas

If the mould covers an area larger than 10 square feet, it's best to seek professional help.

Large infestations often indicate a significant underlying problem that needs professional expertise to resolve.

Hidden Mould

If you suspect mould growth but can't see it (due to musty odours or health symptoms), professionals can use specialised equipment to detect and remediate hidden mould.


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Health Concerns

If anyone in your household has health issues related to mould exposure, such as severe allergies or asthma, it's crucial to have professionals handle the mould removal to ensure thorough and safe remediation.

Recurrent Mould Problems

If mould keeps returning despite your efforts to clean and prevent it, this indicates a persistent moisture problem that needs professional assessment and correction.