What Causes Mould in Bathrooms?

What Causes Mould in Bathrooms

What Causes Mould in Bathrooms?

Mould is a hazard wherever it can be found, whether that is in your kitchen or your bedroom. Unfortunately, Mould can grow anywhere, even in your bathroom.

This creates a serious health hazard as our bathrooms are rooms which we use on a daily basis. Breathing in all of the moulds is nothing but trouble for you and your loved one’s health.

That is why at I-Sells we are dedicated to helping our blog readers and customers understand what they are dealing with, whilst offering solutions.

In this article, we will answer the question ‘What causes mould in bathrooms?’

But first, let us give briefly help you understand what mould is.

Should I be worried about mould?

Mould, otherwise known as damp, is a fungus that grows on wet surfaces. Mould comes in a variety of colours: Black, Green, Brown, Grey and White. It can be difficult to identify mould by colour as it can occur in many shades. Some of the most common mould strains in the home are:

  • Black Mould – Also called Stachybotrys chartarum, Black mould in bathrooms is common, and in wet rooms, but can also occur on cold exterior walls in habitable rooms such as the bedroom or living room.
  • Cladosporium – Commonly found in bathrooms, under sinks, and around faucets but it can grow on surfaces like carpets, furniture, walls, and floors.

Mould reproduces from tiny spores. The spores float through the air and deposit on the surfaces. Under adequate temperature, moisture, and nutrient conditions, the spores can form new mould colonies.

Mould can severely affect your immune and respiratory system, as the spores are easily breathable and not prominent enough to see through the human eye.

People with allergies may be more sensitive to moulds. People with immune suppression or underlying lung disease are more susceptible to fungal infections.

Individuals with chronic respiratory disease may experience difficulty breathing. Reactions vary from fever, a cough, red or itchy eyes, marks on the skin and much more.

If you or your family members have these conditions, a qualified medical clinician should be consulted for diagnosis and treatment.

How is mould made?


Mould in your home generally occurs as a result of condensation.

Condensation occurs when heat and moisture in the air are confined to a certain area, as this heat tries and fails to escape, droplets of water are created on cold surfaces. A good way to think about this is having a hot shower on a cold day and not opening your window.

The reason condensation creates mould is that a damp and humid environment is the optimum condition for mould to grow. Especially in your bathroom – hence why mould in bathrooms is a common occurance. A room that generally sees a large amount of condensation.

The true danger of mould is that its particles can travel through the air without us seeing it, incidentally, this means opening a window with mould on it runs the risk of that mould being blown inside your bathroom alongside the fresh air.

That being said, condensation is not the only cause of mould, it can occur from leaks in the structure of a building too.

So how does this relate to bathrooms?

Humidity and eventually condensation can occur in a bathroom for a variety of reasons, which eventually leads to mould. These are just a few contributors:

Drying towels on the radiator without opening a window

Heaters are not made for the function of drying your clothes. If you do use them for this function, at the very least keep the room ventilated. The excess moisture if not allowed an exit will cause condensation, thereby creating mould in bathrooms.

Keeping the room unventilated

Keeping a bathroom door closed whilst not opening a window will not help regulate the temperature of the room when you shower or take a bath, facilitating the growth of mould in bathrooms. This can be made worse when neglecting to use a bathroom extractor fan in conjunction with window ventilation.


Structural issues in a building can cause moisture to travel through an outside wall to the inside, this in conjunction with fluctuating temperatures inside and outside, along with the condensation created in the bathroom can cause mould in bathrooms to develop.

If you want to know how to reduce condensation in your home, take a read at our blog which has all the information you need here.

If you have found mould in bathrooms or any room in your home, you need to assess if this is your landlord’s responsibility (for example it could be from a leaking roof that needs repairing). Or if the dampness is caused by improper ventilation. To assess your options, click here.

If you’re a tenant and not sure about your rights when it comes to mould in a home you are renting, check out our blog for the answers you need.

As we continue, we are going to share our anti-mould solutions.

Solutions for mould in bathrooms


At I-Sells, we are here to help you combat the scourge of mould with the solutions that we offer, here are some options available in our mould control section.

Note: In any instance of cleaning or dealing with mould, one should at the very least, wear a mask and gloves.

Kair Anti Mould Paint 1 Litre White
Kair Anti Mould Paint 1 Litre Magnolia

Painting over mould with regular paint will not get rid of it. It will only seep through the layer of paint you added. For best results, you should wash mouldy surfaces with Kair Anti Mould Surface Cleanser Concentrate. Specifically designed to clean and treat mould growth areas.

Kair Anti Mould Paint is an excellent, premium quality, low odour anti mould coating guaranteed to protect against unsightly and unhygienic black mould even when there is persistent condensation.

Offering 5 years’ worth of protection against black mould growth on walls and ceilings. We offer options of white anti-mould paint and anti-mould paint in Magnolia.

The unsurpassed performance is achieved by combining modern paint technology with highly advanced, proven biocides. The anti-mould biocide is combined throughout the paint film, which is formulated to impart toughness, elasticity, water resistance and durability to the finish. You’ll find with this product that it is:

  • Easy to use
  • Fast Drying
  • Low Odour
  • Ideal for walls and ceilings
  • Long-lasting protection
  • Matt Finish

To prepare the paint you must ensure any working area is protected and well-ventilated. Remove any loose or flaking material, including paint and paper and make good any cracks or defects.

On new plasterwork or porous surfaces, apply an initial coat of Kair Anti Mould Paint thinned up to 10% with water. New plasterwork should be allowed to dry for 7 – 14 days before any decoration.

Kair Anti-Mould Additive For Emulsion & Gloss Paint – 50ml

Maybe you don’t want white or magnolia, we have got you covered if that’s the case. Our unique Anti-Mould paint additive contains a fungicidal additive that allows you to secure anti-mould properties to:

  • Emulsion paint
  • Eggshell paint
  • Tile grout
  • Gloss Paint
  • Wallpaper paste
  • Coatings

This means alongside having anti-mould paint in colours, you can also secure your tiling grout making your shower, kitchen or bathroom anti-mould, alongside your wallpaper.

Simply apply one 50ml bottle to any 2.5L bucket of paint that fits within the parameters mentioned above and mix thoroughly.

Want to secure your home from mould? We offer the Kair Mould Control Pack, a bundle with the previously mentioned surface cleaner, and two 50ml anti-mould additives, saving you 15% more than if you were to buy individually.

Alongside our mould control products, we also offer the intrinsic instrument needed to negate mould, bathroom extractor fans. You can explore our range here, we also have a couple of blogs to help you decide which fan works for you, and how to install a bathroom extractor fan.

It is our responsibility to clarify that even though these products will help you get rid of mould in bathrooms, they will still come back if you neglect the maintenance needed to have a mould-free environment.

Helping you prevent and remove mould in bathrooms


We at I-Sells endeavour to make sure our customers have all the information they need before making the choice to invest in our mould solutions. Be sure to visit our blog page to gain knowledge on the wide array of factors and issues surrounding ventilation, mould, condensation, and much more.

We hope to have helped you understand the importance of ventilation whilst also helping you understand what causes mould in bathrooms.

We understand you may have more questions regarding mould in bathrooms and mould control overall, please do not hesitate to contact us for more information with regard to any queries you may have. If you’d like to send us an email, click here. For other contact options, see below:

Call us on 020 8463 9696

Visit us at our showroom:


Monday – Friday: 8:00am to 17:30pm
Saturday: 9:00am to 12:00pm
Sunday: Closed

15 St John’s Parade
DA14 6ES
United Kingdom

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