Frequently Asked Questions Relating to Mould

Mould in the home is typically caused by excess moisture, which creates the ideal environment for mould spores to grow and spread. The main sources of this moisture include:

• Poor Ventilation – Inadequate airflow in areas like bathrooms, kitchens, and bedrooms can lead to a build-up of condensation and humidity.
• Condensation – When warm, moist air meets cold surfaces such as windows, walls, or tiles, condensation forms and provides moisture for mould to thrive.
• Leaks and Water Damage – Leaking roofs, pipes, or windows can introduce persistent dampness inside walls and ceilings, creating hidden mould growth.
• Rising Damp – Moisture from the ground can rise through walls if there is no proper damp-proof course or it has failed, especially in older properties.
• High Humidity Levels – Homes with consistently high indoor humidity (over 60%) can experience mould issues, particularly in climates with damp weather.
• Flooding or Damp Basements – Flooding or water ingress into basements and cellars can lead to long-term damp conditions ideal for mould growth.

Controlling moisture through proper ventilation, insulation, and prompt repairs is key to preventing mould problems.

Small areas of surface mould; typically caused by condensation on windowsills, bathroom tiles, or walls, can often be safely cleaned by homeowners using household mould removers, white vinegar, or a mild bleach solution. It's important to wear protective gear like gloves and a mask, ensure the area is well-ventilated, and dry the surface thoroughly afterwards to prevent regrowth.

However, if the mould covers a large area (more than 1 square metre), keeps returning despite cleaning, or is caused by leaks, rising damp, or structural issues, it's best to call in a professional. An expert can identify the root cause, safely remove the mould using specialist equipment, and help prevent it from coming back.

Yes, in most cases, you’ll need to remove as much as possible from the affected room before mould removal begins. This helps prevent contamination and allows out team to work efficiently.

Here’s what to consider:

What to Remove:

• Furniture & Belongings – If possible, move items to another room to protect them from mould spores. If some furniture can’t be moved, cover it with plastic sheeting.
• Clothing, Bedding & Soft Furnishings – Wash any fabrics that may have been exposed to mould. Items that can’t be washed should be sealed in plastic bags until you can assess their condition.
• Electronics & Personal Items – Remove anything valuable or sensitive to dust, moisture, or chemicals.

What to Leave Behind:

• Heavily Contaminated Items – If mould has deeply affected certain objects (carpets, upholstered furniture, or paper materials), professionals may advise disposal rather than removal.

Additional Considerations:

• We usually seal off the room and use air filtration systems to prevent mould spores from spreading.
• If you’re unsure about specific items, we will be able to guide you.

Whether you need to vacate your property during mould removal depends on the extent of the issue and the methods used for remediation. Here’s a general guide:

When You Can Stay:

• Small to moderate mould issues (e.g., bathroom walls, small patches on ceilings, or isolated spots in one or two rooms).
• If the work is limited to a specific area and containment measures (like plastic sheeting and air filtration) are in place.
• If non-toxic cleaning agents are used, and there’s minimal disruption.

When You Should Consider Leaving:

• Severe mould infestations affecting multiple rooms or large structural areas.
• If professionals use strong chemicals that could cause irritation or health risks.
• If you or anyone in the household has allergies, asthma, or respiratory issues that could be aggravated by airborne spores.
• If the remediation requires tearing out and replacing materials like drywall, flooring, or insulation, which can be disruptive and noisy.

Most professional mould removal jobs take precautions to minimise exposure, but if in doubt, the company handling the remediation should be able to advise you on whether it’s safe to stay.  

The Social Housing (Regulation) Act 2023, mandates that social landlords address damp and mould hazards within strict timescales, and strengthens the powers of the Regulator of Social Housing and the Housing Ombudsman. 

As part of the government's mission to transform the safety and quality of social housing, the law that will come into force from October 2025, forces social and private landlords to investigate and fix dangerous damp and mould within a set amount of time as well as repair all emergency hazards within 24 hours of being reported.

The Act places the responsibility of property maintenance, including mould prevention and removal, squarely on landlords and strengthens the powers of the Housing Ombudsman, allowing them to take action against landlords who fail to address issues or comply with the law, and hand out unlimited fines for serious breaches.

If mould keeps returning after it has been cleaned, it usually means the underlying cause has not been resolved. Mould needs moisture to grow, so recurring problems can be caused by condensation, high humidity, poor ventilation, water leaks or damp within the building.

Professional mould remediation looks beyond simply removing the visible mould. Identifying and addressing the source of excess moisture is an important part of providing a longer-term solution and helping to prevent the mould from returning.

Black mould can potentially affect health, particularly when people are exposed to it for prolonged periods. Mould releases spores into the air which can cause or aggravate respiratory problems, allergies and conditions such as asthma. Children, elderly people and those with existing respiratory conditions or weakened immune systems can be particularly susceptible.

For this reason, significant or recurring black mould should be properly investigated and treated rather than simply painted over or repeatedly wiped away. The website's mould-and-health information discusses these risks in more detail.

No. Painting directly over mould may temporarily hide the problem, but it does not remove the mould or address the moisture that allowed it to develop.

The mould should first be properly treated and the underlying cause identified. Once the affected area has been successfully remediated and is sufficiently dry, it can then be redecorated using suitable products and finishes. Mould-resistant or breathable paints may also be recommended depending on the property and the cause of the problem.

Damp describes unwanted moisture within a property and can have several causes, including leaks, penetrating damp or rising damp. Condensation occurs when warm, moisture-laden air comes into contact with a colder surface, such as a window, external wall or ceiling.

Mould is a fungal growth that can develop when surfaces remain damp or when humidity levels are consistently high. Identifying whether moisture is being caused by condensation, a leak or another form of damp is therefore important when deciding on the correct mould treatment.

Yes. Mould can sometimes develop in concealed areas such as behind furniture, wallpaper and kitchen units, underneath flooring or within wall and ceiling voids.

Warning signs can include a persistent musty smell, staining or discolouration, peeling paint or wallpaper and recurring condensation. If you suspect hidden mould, a professional inspection can help identify the extent of the problem and the possible source of moisture.

Keeping moisture and humidity under control is one of the most important ways of reducing the risk of mould returning. This can include regularly ventilating bathrooms and kitchens, using extractor fans, avoiding excessive indoor humidity and dealing promptly with leaks or water ingress.

It is also important to follow any recommendations made following professional mould remediation. Depending on the cause, these may include improving ventilation, repairing leaks, addressing damp or using appropriate mould-resistant materials and finishes. Mould Solution Services' remediation process specifically includes preventative measures aimed at reducing future mould growth.

Mould Solution Services provides professional mould removal, cleaning and remediation services across Hertfordshire, Bedfordshire, Essex and North London.

Based in Hertford, we cover towns and surrounding areas including Hertford, Ware, Bishop’s Stortford, Stevenage, Welwyn Garden City, Hatfield, St Albans, Watford, Hemel Hempstead, Hoddesdon, Broxbourne and Cheshunt, as well as Enfield and other areas of North London. We also provide our mould treatment services throughout neighbouring areas of Bedfordshire and Essex.

If you are unsure whether we cover your location, please contact us. We regularly travel throughout the region to provide mould inspections, professional mould removal and long-term mould remediation solutions for homeowners, landlords and commercial properties.