How to Get Rid of Mould On Walls Permanently

As professional painters and decorators, a key part of our job is to thoroughly prepare the substrates we’re going to be painting and one of the more frequent issues we must solve is getting rid of mould on walls permanently. Whilst many DIYers (and some professionals for that matter) try to solve the problem with a coat of waterproof paint, this is a temporary solution and in the end, is just going to be a waste of time and money.

Of course, whilst mould looks unsightly, it also poses multiple health hazards such as allergic reactions and asthma attacks so not only are you going to want to remove mould permanently from your home for aesthetic reasons, but it’s also beneficial to your overall well-being.

With that being said, we’re going to go through the process we use to get rid of mould on walls permanently so you don’t need to worry about it returning.

What Causes Mould to Grow On Walls?

Whilst there are plenty of easy solutions for removing mould from walls, to ensure you remain mould-free in the future, it’s important to understand what’s causing the mould to grow in the first place.

Mould grows on walls due to excess moisture so controlling the levels of moisture inside your home will dramatically help the inhibition of mould growth. Besides moisture, mould also needs nutrients to grow but within the home environment, this isn’t usually an obstacle for mould growth as it can grow on virtually any organic substance.

Mould can grow on walls for a multitude of reasons including leaking plumbing, inefficient roofing which allows rain to get inside your home and condensation due to high humidity (most commonly occurring in the bathroom).

How to Get Rid of Mould On Walls Permanently

Whether you’re looking to remove black mould from your bedroom walls, bathroom or elsewhere within your home, there are some simple steps you can follow to ensure your mould problem doesn’t return.

Tools for the job:

  • Gloves
  • Dust mask
  • Safety goggles
  • Scrub brush
  • Detergent
  • Sanitiser
  • Kitchen roll
  • A fan
  • Vacuum cleaner

The removal process:

  1. Put on your PPE
  2. Open your windows to provide the room with ventilation
  3. Use the vacuum to carefully remove any mould spores on the surface of the wall
  4. Apply detergent to your scrub brush – try to avoid saturating the brush with too much detergent as you don’t want to provide the mould with additional moisture
  5. Scrub the wall in a circular motion
  6. After the area containing mould has been thoroughly rubbed down, use some kitchen roll to thoroughly dry the area
  7. Use sanitiser wipes to wipe down the affected area – this should remove any remaining mould on the surface of the wall
  8. Repeat step 6
  9. Use the fan to dry out the area
  10. Leave the wall for 24 hours and assess if the removal process has worked. If it hasn’t fully worked, simply repeat the steps above again.

Once you have followed these steps, it’s well worth investing in a dehumidifier to ensure that the mould doesn’t grow back in the future.

We would recommend something like the Kesnos dehumidifier which is relatively cheap when you think about how much money it will save you if your mould problem gets worse in the future. This particular dehumidifier can store around 50 pints of moisture per day so depending on the moisture levels in your property, you shouldn’t need to perform the laborious task of emptying it constantly.

Most importantly, it works well at creating an environment where mould growth becomes virtually impossible and thus helps to remove mould from your walls permanently.

Not-so Simple Fixes

Unfortunately, if your mould build-up is the result of severe environmental factors, easy fixes such as those mentioned above are simply not going to work. For example, if you don’t have a proper ventilation system in your bathroom and your shower is used multiple times a day, removing the mould from the walls and painting over it with anti-mould paint isn’t going to be a sustainable solution.

With that in mind, here are some systems that will adequately control condensation within your home and create an environment in which mould struggles to thrive.

Positive Input Ventilation

Positive input ventilation (or PIV) has been around since 1972 and is currently installed by an estimated 1 million homes in the UK as a cost-effective solution to condensation.

PIVs are typically installed in the loft area and as air from the home enters this ventilated area, it passes through filters and enters the rest of the home through a ceiling diffuser. The air then dilutes, displaces and replaces contaminated air with fresh, filtered air. As a result, the home environment becomes such that condensation simply cannot exist.

As well as preventing condensation build-up (and the consequent mould build-up on walls), PIV can also reduce airborne pollutants such as fumes and pollen as well as other harmful gases such as radon, C02 or VOCs from oil-based paints.

Of course, with such a positive impact on the safety of your home, many PIVs come at a great cost. For example, one of the best PIVs on the market, the Nuaire Drimaster Eco, will set you back north of £500.

Positive Pressure Ventilation

Much like PIVs, positive pressure ventilation works to displace moist and contaminated air with the key difference being that (as the name suggests) they gently increase the pressure within your home to facilitate better air circulation.

Again, positive pressure ventilation systems are installed in the loft area and come at a hefty price tag of £400+.

Passive Vents

One of the most cost-effective ways to ensure your home inhibits the growth of mould is to install passive ventilation systems. Cheap to purchase and incredibly energy efficient, passive vents work by using natural external wind pressure and thermal buoyancy to allow fresh air into buildings.

Theoretically speaking, passive vents achieve the same outcome as opening windows but of course offer more safety and are more energy-efficient.

Whilst the cost of the vents themselves is relatively cheap, you may need to pay someone to install them for you.

Best Mould Remover for Painted Walls

If you’re dealing with mould that is particularly troublesome, there are a few specialist products worth investing in to remove it.

The two that stand out for me are Wykamol Mould Eradication Kit which contains a powerful mould remover as well as a full safety kit (which you’ll definitely need as this is strong stuff).

You could also use HG’s mould remover foam which works well to safely remove black mould from walls as well as many other surfaces.

Best Anti Mould Paint

We’ve already gone through considerable testing to find the best anti-mould paint so I’ll keep this section short (although feel free to read our full reviews here). Just to reiterate what we wrote, if you’re looking for an anti-mould paint that actually works, you’re best off going with Ronseal’s version. Granted, it’s far more expensive than other brands but when it comes to long-term protection, it will actually save you money.

Top tip: It’s always worth using a primer such as Zinsser 123 after cleaning the mould as it’s a primer and stain blocker in one and also provides the anti-mould paint with a solid base coat which helps with opacity.

Final Thoughts

Whilst many people find that cleaning mould from their walls is a temporary solution, hopefully, you can come away from reading this armed with the knowledge to make mould a thing of the past.

If your mould problem isn’t too troublesome, a good clean and a couple of coats of anti-mould paint should do the job. If your mould problem is more severe and the result of environmental factors, it’s definitely worth considering investing in systems which will not only inhibit mould growth but will provide you with a safer living environment too.