15 June, 2021

Once mould gets its grip in grout, or mildew makes its mark on walls, they can both be very difficult to remove.

These toxic types of fungi thrive in dark, damp areas, so they can often be spotted on bathroom walls, in shower recesses, and on tiled floors in wet areas.

If you suspect there is mould or mildew growing in your bathroom, it’s essential to act fast to prevent any health issues such as respiratory illness or structural damage to your home.

Here’s how to get rid of mould and mildew in your bathroom, and a few ways to discourage both from re-sprouting in the future.

What's the difference between mould and mildew?

The simplest ways to distinguish between mould and mildew is by colouring and texture. Mildew is characterised by its greyish white colour and powdery texture which can turn dark if neglected, whereas mould is black and fuzzy.

Of the two, mould is much harder to eradicate, and can become quite dangerous if it builds up. Though mould sensitivity can vary from person to person, mould can easily induce allergies or cold-like symptoms if left untreated for too long.

Combination of mould and mildew on wall
A combination of mildew and mould on a wall

How to get rid of mildew

Mix and spray white vinegar and baking soda

Luckily, most cases of mildew can be quickly and effectively removed with a few household items.

In a spray bottle, mix one-part white vinegar to two-parts baking soda and spray areas covered with mildew then let the solution sit for a few hours. Use a damp cloth to then scrub the mildew off and rinse the entire area with water.

If the mildew persists, apply a paste of three-parts baking soda and one-part water, then use a bristled brush to scrub and lift it. Repeat this process until no mildew remains.

How to get rid of mould

To begin with, turn on your bathroom fan and if possible, a window for ventilation, before getting close to the affected area. This can help prevent inhalation of toxic mould spores. Mould spores are carried through the air and can cause health problems including wheezing, eye or skin irritation and cold-like symptoms.

Scrub surfaces with a vinegar mixture

Though it may be tempting to reach for a store-bought mould killer for the quickest solution, opting for a natural remedy like white vinegar can prevent mould from returning. This is because bleach and many other mould cleaners work only to alter mould or mildew colour (or to reduce mould for a short period of time), whereas natural solutions, when used regularly, work to kill mould spores and prevent fungi from returning.

Using gloves, give all mould-affected areas of your bathroom a solid scrub. There are plenty of mould-killing chemical solutions on the market, but a mix of four-parts white vinegar to one-part water can be just as effective.

Generously spray your solution over the entire mould-affected area, and use a scrubbing brush vigorously to lift mould off the surface. If mould has seeped into cracks or crevices in your tiles, use an old toothbrush to scrub in tight spaces. Do not use a brush before the vinegar mixture has been applied, as dry brushing could flick mould spores into the area where they may be inhaled.

Person scrubbing mould off a wall

After the mould has been lifted and removed, dry the area with a cleaning cloth. It’s essential to remove all liquid from this area to prevent mould returning, so pay special attention to small crevices or corners where liquid may pool undetected.

No matter what product or solution you use, make sure you thoroughly rinse your cloth or brush after you’ve cleaned a mould-affected area to ensure you aren’t spreading the problem elsewhere. You should also wear gloves during mould removal so you aren’t touching mould with your bare hands.

If necessary, re-grout

Unfortunately, once mould seeps into grout it is almost impossible to remove altogether. If you're unable to lift the mould with a heavy-duty scrub, re-grouting the affected area may be the best way to eradicate mould for good.

After scraping mould, dirt and dust away, you’ll need to remove the existing grout with a grout saw. These are available at most hardware stores for around $20. Once the grout has been removed and the gap between affected tiles is clear, spread your new grout mix across and into it, using a grouter to apply and smooth it.

After the grout has dried, use a sponge to mop up any excess material, and a cleaning cloth to buff the tiles. Applying a grout sealer 48 hours after grouting will ensure its longevity.

Other mould removal remedies

If the vinegar and water solution was unsuccessful, here are a few other non-toxic remedies to try:

When to call a mould removal expert

If you notice mould has spread to cover a large, unmanageable section of your bathroom (anything larger than 1sqm), it’s best to call a mould removal specialist.

How to prevent mould and mildew re-sprouting

Use products that limit moisture

A dehumidifier is a simple and efficient solution to remove moisture and potential mould from your bathroom. Often working in tandem with a bathroom exhaust fan, a dehumidifier collects moisture from the air, and can drastically reduce dampness in just a matter of hours. If used regularly, moisture levels in the air will drop over time – as will your chances of mould or mildew reappearing.

Person removing water from a dehumidifier

Moisture absorbers are another useful tool to soak up excess dampness. Available at local hardware stores, these compact and convenient products are very affordable and can last up to 60 days (with refills available if needed).

Increase natural light and ventilation

Mould grows in damp, dark areas, so maximising your bathroom’s natural light and ventilation sources is extremely important. To increase airflow, make sure your exhaust fan is switched on when hot water is running, and if you have a bathroom window, leave it ajar for at least 30 minutes after a bath or shower.

Keep ‘wet areas’ dry after use

Mould can’t grow without moisture, so make sure wet areas in your bathroom, including basins, showers and baths, are wiped dry after use.

It’s also useful to spot any leaks that could cause damp when left unmonitored. Check the wall behind your toilet, the faucets on your bathroom taps and your showerhead. If you notice any leaks, fix them immediately before mould has the chance to sprout near them.

The same logic applies to bathroom accessories like towels and toiletries. Make sure you rotate your towels frequently to avoid any potential mould growth, and don’t leave wet towels rolled up or in piles for too long. If you use a loofah or washer in the shower, let it dry and then store it in a dry location to prevent mildew from forming.

Maintain a regular cleaning schedule

As mould feeds on organic matter, such as dust or dead skin cells, maintaining a regular and thorough bathroom cleaning schedule will limit the chance of it reappearing. Make sure your schedule includes dusting with a damp microfibre cloth at least once per week to limit build-up.

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