Mould doesn't have to be a dirty word!

To grow, mould requires the presence of: 

1. Moisture

2. A food source

3. Oxygen
   

When all three of these are available, mould will grow. 

Its important to note that mould cannot grow on glass, acrylic paint, ceramic tile surface etc, if clean. However, it can develop on dust / dirt on one of these surfaces as this provides the organic "food source" which it requires.  Keeping mould prone areas such as bathrooms, laundries and kitchens clean, will help a lot.

Cleaning regularly with a sponge and sugar soap solution will work well, but homemade vinegar/water mix will also be effective. (if you don’t mind the smell). Whatever mix you use - just make sure, the cleaning is done on a regular basis. A note that using a spray bottle is not recommended as it can spread the mould spores.

Lets talk about humidity

The ideal humidity is 45-50%. When the levels rise, the air will feel damp and this is the ideal environment for mould to develop. A humidity monitor can be purchased for as little as $10, and will provide an accurate humidity level reading. 

If the humidity level is consistently above 50%, then action should be taken to reduce the level. This can be achieved through ventilating the room by opening a window on a warm dry day. Investing in a dehumidifier will ensure that moisture can be removed from the air throughout the Winter months too.  An fan will not do this, so even if you use an exhaust fan and open a window during a shower, you may still get mould growth. A dehumidifier with a 1000ml capacity can cost as little as $99 and these can be left on, with doors and windows closed and will usually turn off when the water tank capacity is reached. 1000ml capacity is a good size for a regular bathroom. 

A leak or condensation related issue?

The presence of mould in a bathroom may be related to an issue with the common property e.g. a leak from an adjoining unit, but this will present quite differently to a condensation related issue.

Leak related mould growth You can see clear evidence of a water stain, bubbling paint and localised mould growth. Before work is done to repair this ceiling, the cause of the leak above must be resolved. Once this is done, the ceiling will be scraped back and repainted with a sealing coat followed by a top coat of bathroom paint.

Condensation related mould growth

This image shows generalised mould growth over the entire ceiling. This will be caused because the bathroom is not properly ventilated and the ceiling is unclean. In this case, a bucket of warm soapy water should be used to clean off all the mould and grime. The owners should repeat this process every few months. The humidity level must be kept in the comfort range 45-50% by opening a window for extended periods (on warm dry days) if possible, or by using a dehumidifier.