How to Remove Mould from Walls and Ways to Stop It Coming Back

Black mould on a wall is unpleasant to look at, but simply wiping it away or painting over it usually isn’t enough.

For a longer-lasting solution, there are three things to think about:

1. Remove and treat the existing mould.
2. Work out where the moisture is coming from.
3. Protect the surface against future mould growth.

At Kingfisher Building Products, we’ve been manufacturing mould control products in the UK since 1988. Our mould treatment system includes Mould Cure and Thermapaint Anti-Mould Paint and Anti-Mould Paint, giving you practical options for treating existing mould and protecting walls and ceilings afterwards.

Not sure which one you need? Our technical team is happy to help you choose the right solution before you buy.

Why Is Mould Growing on My Walls?

Mould needs moisture to grow, which is why it commonly appears in bathrooms, kitchens, bedrooms and other areas where humidity is high or surfaces become cold.

Typical problem areas include:

• Around windows and window reveals

• External wall corners

• Bathroom walls and ceilings

• Behind wardrobes and large furniture

• Kitchens and utility rooms

• Cold bedroom walls and ceilings

Condensation is a particularly common cause. Warm, moisture-laden air meets a cold wall or window, cools down and leaves moisture on the surface. If this happens regularly, mould can begin to grow.

Cooking, showering and drying clothes indoors can all add moisture to the air.

However, not every mould problem is caused by condensation.

Could It Be a Damp Problem Instead?

Look at where the moisture appears and when it becomes worse.

If a damp patch becomes more noticeable during or after rain, investigate possible penetrating damp, such as damaged pointing, cracked render, leaking gutters or another external defect.

Persistent dampness at the bottom of a ground-floor wall may have a different cause and should be properly investigated before choosing a treatment.

Whatever the cause, the principle is the same:

Treat the mould, but also deal with the moisture that is feeding it.

No mould treatment or decorative coating can repair a leaking gutter, failed pointing or another building defect.

The Kingfisher Mould Control Solution

For typical black mould on internal walls and ceilings, we recommend approaching the job as a simple Treat → Protect → Prevent process.

Step 1: Treat Existing Mould with Kingfisher Mould Cure

If mould is already present, start with Kingfisher Mould Cure.

Mould Cure is Kingfisher Building Products’ purpose-made fungicidal cleaner and surface sanitising treatment for common black mould on suitable internal painted finishes and hard surfaces.

It’s designed to deal with the existing fungal growth and spores before you redecorate.

Mould Cure is particularly useful for areas such as:

• Bedroom walls and ceilings

• Bathrooms

• Kitchens

• Window surrounds

• Tiles and grout

• Utility rooms

• Cold external walls

• Areas behind furniture

Why Use Mould Cure Before Painting?

Because painting directly over existing mould doesn’t properly prepare the surface. Treat the contamination first, allow the wall to dry and then apply the appropriate protective coating.

How to Use Mould Cure

Follow the instructions supplied with the product carefully.

Prepare and apply Mould Cure according to the label, treating the affected area and surrounding surface as directed. Once treatment is complete, allow the wall to dry fully before redecorating.

Always ventilate the room and follow the product's safety and application guidance.

Already have visible black mould? Start with Mould Cure.

Step 2: Choose the Right Kingfisher Anti-Mould Paint

Once the existing mould has been treated and the surface is clean and dry, you can protect the wall with a specialist coating.

Kingfisher offers: Thermapaint Anti-Mould Paint

Best suited to rooms where condensation and cold surfaces are contributing to the mould problem.

Kingfisher Thermapaint Anti-Mould Paint combines decorative anti-mould protection with thermal properties designed to help reduce surface condensation.

Its formulation contains thermal micro-beads alongside active-film fungicidal protection, so it tackles the problem in two ways:

Condensation control: helping reduce moisture forming on colder wall and ceiling surfaces.

Mould protection: helping make the finished painted surface resistant to further mould growth.

Thermapaint is particularly useful for:

• Cold external walls

• Bedrooms

• Bathrooms

• Kitchens

• Utility rooms

• Window surrounds

• Properties with recurring condensation problems

• Areas behind furniture where airflow is limited

And because it’s a decorative coating, you don’t have to choose between practical protection and how the room looks. It’s also available in a wide choice of colours as well as more traditional neutral finishes.

A Simple Thermapaint System

Existing mould → Treat with Mould Cure → Allow to dry → Apply Thermapaint Anti-Mould Paint

This is the solution we’d point customers towards when condensation and recurring black mould are both part of the problem.

If condensation itself isn’t the main issue but you want a specialist coating that helps resist mould growth, Kingfisher Anti-Mould Paint provides another option.

It applies by brush or roller in much the same way as conventional decorative paint but creates a fungicidal painted finish designed to resist mould growth.

It’s particularly suitable for walls and ceilings in areas where mould protection is required after the existing contamination has been properly treated.

A Simple Anti-Mould Paint System

Existing mould → Treat with Mould Cure → Allow to dry → Apply Kingfisher Anti-Mould Paint

The important point with either coating is preparation.

Don’t simply cover existing mould with paint. Treat it first.

Thermapaint or Anti-Mould Paint: Which Do I Need?

The easiest way to choose is to think about what is happening in the room.

Choose Thermapaint Anti-Mould Paint where cold surfaces and condensation are contributing to recurring mould. Its thermal and anti-mould properties make it particularly suited to condensation-prone areas.

Choose Kingfisher Anti-Mould Paint when you primarily need a specialist mould-resistant decorative finish rather than the additional thermal properties of Thermapaint.

Use Mould Cure first whenever you are treating existing black mould before redecorating.

Still unsure? Send our technical team a photograph and a little information about the room and we can help you decide which system is most appropriate.

How to Remove Mould from a Wall

1. Prepare the Area: Move furniture away from the affected wall and protect nearby floors and furnishings.

Ventilate the room and use the appropriate protective equipment specified in the product instructions.

Avoid dry-brushing or sanding mouldy surfaces, as this can disturb spores.

2. Treat the Mould: Use Kingfisher Mould Cure according to the product instructions.

Make sure you treat the affected area thoroughly rather than concentrating only on the most obvious black marks.

3. Let the Wall Dry: Allow the treated surface to dry fully.

Don't rush to paint simply because the surface feels dry to the touch. Porous materials such as plaster and masonry can retain moisture below the surface.

4. Deal with the Moisture Source: Before redecorating, ask why mould appeared there in the first place. A few things to consider:

Is the room poorly ventilated?

Does condensation form on the windows?

Is the affected wall noticeably cold?

Is furniture preventing air circulating?

Is there a leaking gutter or pipe?

Does the damp patch become worse after rain?

Finding the answer now gives your treatment the best chance of lasting.

5. Protect the Surface: Once the wall is properly prepared and dry, finish with either:

Kingfisher Thermapaint Anti-Mould Paint for combined condensation and mould control.

or

Kingfisher Anti-Mould Paint for a specialist fungicidal decorative coating.

How to Help Prevent Mould Coming Back

Products are only part of the solution.

If condensation is contributing to the problem, reducing moisture and improving ventilation will help your mould treatment perform effectively.

Try to:

• Use extractor fans when cooking and showering.

• Keep trickle vents open where appropriate.

• Ventilate rooms regularly.

• Avoid drying wet washing directly on radiators where possible.

• Leave a small gap between furniture and cold external walls.

• Maintain reasonably consistent heating.

• Deal with plumbing leaks quickly.

• Keep gutters, pointing and external finishes in good condition.

For recurring condensation on cold walls, Thermapaint Anti-Mould Paint can provide an additional line of protection once the existing mould has been treated.

Removing Mould from Painted Walls

Painted surfaces need a little care.

Before applying a treatment, check the product instructions and test an inconspicuous area where appropriate.

Avoid aggressive scrubbing that could damage the existing decorative finish.

If the existing paint is already badly stained, loose or flaking, you may need to prepare and redecorate the surface once the mould has been treated and the wall has dried.

For continued protection, finish with Kingfisher Thermapaint Anti-Mould Paint or Kingfisher Anti-Mould Paint, depending on the cause of the problem. Browse more options in our Anti-Mould Paint range.

Removing Mould from Concrete and Masonry

Concrete, brick and other masonry surfaces are porous, so moisture can sit deeper within the material.

Treat mould using a product suitable for the surface and allow plenty of drying time.

Garages, cellars and other cooler areas can take longer to dry than normal living spaces.

If mould keeps returning, investigate why the masonry is staying damp. The underlying problem may be condensation, water ingress or another form of damp that needs a different treatment.

Should I Use Bleach on Black Mould?

Bleach is commonly used because it can quickly lighten dark mould staining, but that doesn't necessarily make it the most appropriate treatment for every wall surface.

For porous building materials such as plaster and masonry, we'd recommend using a purpose-made mould treatment that is designed for the job.

Kingfisher Mould Cure is specifically formulated as a pre-treatment for existing black mould and can be followed by Kingfisher's mould-resistant coatings once the surface has dried.

Whatever you use, never mix different cleaning chemicals together.

Which Kingfisher Product Do I Need?

Here's the simplest way to look at it:

I already have black mould on my wall
→ Start with Kingfisher Mould Cure.

The mould keeps appearing on a cold wall where I also get condensation
→ Treat with Mould Cure, then decorate with Thermapaint Anti-Mould Paint.

I want a specialist decorative paint that helps protect against mould growth
→ Treat existing mould with Mould Cure, then use Kingfisher Anti-Mould Paint.

I'm not sure whether the problem is condensation or damp
→ Speak to the Kingfisher Building Products technical team before buying.

Sometimes the most useful advice we can give is that you need to solve a different problem first.

Kingfisher's 3-Step Approach to Mould

Treat the mould. Protect the surface. Control the moisture. That's the combination that gives you the best chance of keeping your walls looking clean and fresh.

When Should I Get Professional Advice?

Small areas of surface mould may be manageable yourself, but consider professional advice when the mould is extensive, repeatedly returns after treatment or appears to be associated with a leak or building defect.

It's also sensible to seek appropriate advice if someone living in the property may be particularly vulnerable to the effects of damp and mould.

A good specialist should look for the source of the moisture, rather than simply cleaning the visible mould.

If you’re not sure whether yours is a straightforward condensation problem or something more complicated, speak to us first.

Frequently Asked Questions

Can I Just Paint Over Mould?

No. Treat the existing mould first.

Painting over visible mould may disguise the staining temporarily, but it doesn't properly prepare the contaminated surface.

Use Kingfisher Mould Cure, allow the wall to dry and then redecorate with the appropriate coating.

For condensation-prone surfaces, consider Thermapaint Anti-Mould Paint. Where the additional thermal properties aren't required, Kingfisher Anti-Mould Paint provides a specialist mould-resistant finish.

What's the Difference Between Mould Cure and Anti-Mould Paint?

They do different jobs.

Mould Cure treats existing mould.

Anti-Mould Paint helps protect the finished surface against mould growth after treatment.

Think of Mould Cure as the treatment and the paint as the protection.

What's the Difference Between Thermapaint and Anti-Mould Paint?

Both are designed to provide anti-mould protection.

Thermapaint Anti-Mould Paint also incorporates thermal properties intended to help reduce surface condensation, making it particularly useful on colder walls and ceilings where condensation contributes to mould growth.

Kingfisher Anti-Mould Paint is the more straightforward option when your priority is a specialist fungicidal decorative finish.

What Should I Use for Black Mould Around a Window?

First establish why the area is becoming damp.

Black mould around windows is commonly associated with condensation. Treat existing mould with Mould Cure, improve ventilation and moisture control, and consider Thermapaint Anti-Mould Paint on suitable surrounding wall surfaces where recurring condensation is an issue.

What Is the Best Kingfisher Product for Recurring Mould?

It depends on why the mould is recurring.

For existing mould, begin with Mould Control.

Where condensation on cold surfaces is contributing to repeated mould growth, the Mould Cure + Thermapaint Anti-Mould Paint system is designed to combine initial mould treatment with subsequent condensation and mould control.

Where you simply require a specialist mould-resistant decorative coating after treatment, Mould Cure + Kingfisher Anti-Mould Paint may be the more appropriate system.

If you're unsure, contact the Kingfisher Building Products technical team and we'll help you choose the right solution.

Author: Jamie