Cleaning Guides

How to Get Rid of Black Mould in Bathroom

Nobody imagines their bathroom becoming a breeding ground for fungi, but that’s what happens when we postpone the cleaning for too long. Regular mould is nuisance and easy to remove, however, if you spot or smell black mould, that’s when you need to take action right away.

So, if:

Then read along.

Table of Contents:

What is black mould?

This type of mould, known also by its Latin name Stachybotrys Chartarum, should not be underestimated. Unlike the regular strain of mould, this one is slimy in appearance. It’s also greenish-black and sometimes slightly grey in colour. The appearance isn’t what should worry you, but rather what it does.

Black mould releases trichothecene mycotoxins. These neurotoxins can result in the need for serious home repairs, but the bigger problem is how dangerous they are to humans.

Exposure to black mould can result in a number of negative side effects with varying degrees of severity:

  • Dizziness
  • Tiredness
  • Headaches
  • Hallucinations
  • Allergic reactions (sneezing, coughing, watery and itchy eyes, runny nose)

When spores are inhaled for a longer period of time, some of these symptoms may occur:

  • Nausea
  • Skin irritation
  • Asthma
  • Lung infection
  • Bleeding in the lungs
  • Swelling of the lungs

Black mould in the bathroom – causes

This type of fungi germinates in very specific conditions which, sadly, are often times found in your bathroom. Perfect conditions for black mould growth include:

  • Poor ventilation – it makes it hard for humidity to escape, resulting in moisture build-up and wet areas stay wet for a longer time.
  • Condensation – when warm air gets in contact with a cold surface it becomes water drops. This adds to the next condition.
  • Humidity – black mould needs about 90% humidity to start growing. This percentage is not hard to reach when you have condensation and poor ventilation in a room.
  • Warmth – black mould can grow in different temperatures, but does it best when it’s warm.
  • Darkness – it doesn’t need light to grow, in fact, large quantities of light can actually kill this fungus.
  • Oxygen – like all living beings, this one needs oxygen as well. However, it won’t die even if you manage to deprive it of oxygen. It will go into a dormant state until it senses oxygen again. This dormant state can last quite a few years.
  • Time – Normal fungi only need from 24 to 48 hours to start growing whereas these need several days (8 to 12).

How to get rid of black mould in the bathroom

There are several areas in your bathroom which are prone to black mould growth because they collect the most moisture. These include:

  • Tile grout
  • Shower tiles
  • Window sills
  • Around sinks
  • Bathtub
  • Ceiling

Some of these surfaces are easier to clean, than others.

Before you even start to remove black mould from your bathroom, make sure the following protection measures are at hand:

  • Safety mask
  • Safety goggles
  • Long rubber gloves
  • Ventilation (have your room ventilation fan switched on)

You can tackle the problem by using either commercial cleaners or natural means.

Commercial cleaners

If you don’t have time or don’t trust DIY solutions, then commercial products are just for you. However, they release harmful fumes so make sure no pets or children are around when cleaning.


  • Mix one part of this almighty compound with 4 parts of water.
  • Pour into a spray bottle.
  • Apply to the nasty black mould. Bleach is really strong even when diluted with water, so it will instantly kill the nasty fungi.
  • Wait about an hour.
  • Wipe away the mixture.

Keep in mind that this substance can damage paint, if that’s where the mould is located. Always test the chemical on a small spot to see its effects before going all the way.

Mould eradication kits

You’d find countless different brands both online and offline. Whichever one you choose, the important thing to know is to always follow the instructions on the packaging. Some of these kits come with their own protective gear and include several products which are used one after the other in a strict order. You have to be very careful when using this kind of strong chemicals.

Anti-bacterial sprays

Usually these are not bleach-based, so they won’t damage any paintwork, hopefully. Anti bacterial sprays are easy and quick to apply, but might not be able to remove any mould stains. The good thing is, they are great to spray every once in a while, to make sure the fungi will not return.

Never mix any of these commercial cleaners with one another!Every product should be able to get the job done on its own. Read more about what cleaning products you should never mix.

Natural non-toxic cleaners

If you prefer to remove black mould with the help of eco-friendly means, then use:

Tea tree oil

  • Mix tea tree oil with water, and pour into a spray bottle.
  • Spray the solution onto the spores.
  • Wait several hours for the mixture to set.
  • Scrub away the mould.

Vinegar and baking soda

  • Pour white distilled vinegar in a spray bottle. Do not dilute it with water.
  • Spray it over the affected area.
  • Wait from 30 minutes to about an hour.
  • Spray some baking soda mixed in water.
  • Scrub until all the spots are gone.
  • Rinse with clean, warm water.

The smell of vinegar will fade away after several hours. Hydrogen Peroxide can be a substitute to vinegar, but it needs to be mixed with water.


  • Mix equal parts of ammonia and water in a spray bottle.
  • Spray the black mould.
  • Wait several minutes for the solution to work its magic.
  • Use a brush to clean the area.
  • Repeat if necessary.
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How to get rid of black mould in bathroom tiles

This method works on other smooth bathroom surfaces such as: a tub or basin.

  • Spray the affected tile until the solution forms a thin coating.
  • Wait until it soaks in.
  • Wipe the black mould with a clean rag.
  • Use a clean side of the rag when the current one becomes too soiled.

You may have to use a brush for more stubborn mould spots.

How to remove black mould from tile grout

To remove black mould from tile grout, you would need to use bleach or another strong chemical. 

  • Spray the affected grout.
  • Scrub with an old toothbrush.
  • Rinse the brush often.
  • Take breaks so you wouldn’t get dizzy from the strong fumes.

Sadly, there’s no guarantee that, even with commercial chemicals, you will manage to remove all the mould from your tile grout. If you are not satisfied with the results, you might consider replacing the old grout with a new one. Do not forget to apply a sealer to prevent future mould growth.

You may also like:
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How to Clean Bathroom Tiles and Make Them Look Splendid Again

How to remove black mould from sealant

Sealant, much like tile grout, is almost impossible to clean from black mould. Here’s what you can do, if the method above doesn’t prove to be working:

  • Take two sheets of toilet paper and roll them together until they form the shape of a cigar.
  • Place the rolled toilet paper on the dirty spot.
  • Pour some bleach on the paper, so it absorbs it.
  • Leave it like that overnight.
  • Remove the paper the next day.
  • Repeat if necessary.

How to remove black mould from shower curtains

To get rid of black mould collected on the bottom of the curtain or any other place on it, simply:

  • Soak the curtain into warm water.
  • Add baking soda and white vinegar.
  • Scrub the dirty spots with a brush.
  • Dry the curtain once you’re done.

How to prevent black mould in the bathroom – maintenance tips

The best way to protect yourself from the wretched black mould is to never allow it to develop in the first place. Since that option is not always available, the best you can do is to follow these maintenance tips, so, hopefully, you’d never have to deal with this fungus again.

  • Wipe down wet surfaces after bath time – this will remove any leftover moisture from tiles, grout and bathtub. Also wipe down the shower curtains if you have any.
  • Don’t leave any wet damp towels on the floor – it’s easy to just leave the towel on the floor after you’ve wiped all the water drops, but don’t do it, because that towel will hold moisture and contribute to the problem.
  • Keep your bathroom well ventilated – after each bath or shower, keep the ventilation fan working for at least 30 minutes. If your bathroom has a window, even better, keep it open. The steam needs to escape from the bathroom.
  • Fix leaks as soon as they happen – minor leaks might be an inconvenience which can wait another day, but they do attribute to more moisture in your bathroom.
  • Keep rugs dry – if you happen to have any rugs in your bathroom, make sure they are always clean and dry.

Hire a professional cleaner

If you feel the task of black mould removal is too tiresome or time consuming for you, you can always book a regular home cleaning session with Fantastic Services. The professionals we work with will have your bathroom looking like new and no black mould will threaten you or your family any longer.

Need help with your bathroom cleaning?

Why not try out our cleaning services.

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Always be on the lookout for mold, especially the back type. Always remember to:

  • Wipe down your bathroom after shower
  • Ventilate as much as possible
  • Fix leaks as soon as they appear


Have you ever had black mould in your bathroom? How did you get rid of it? Let us know down below, so we can start a conversation.

Image source: Shuterstock/ Pumbastyle

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