Many mould and moisture issues are cause by a lack of ventilation within a bathroom. Bathrooms are designed to be a wet room although steam from everyday activities and cause mould to grow in bathroom and other areas of the house if they are not properly ventilated. This especially common in the city units of Sydney, Melbourne and Brisbane.
The four main reasons why bathroom exhaust fans are not adequate is
A bathroom exhaust fan should be installed directly above the shower where the most amount of steam is produced. When the exhaust fan is installed to fair away the steams is allowed to condensate on the ceiling and lead to mould growth.
Often we do not notice our bathroom exhaust fans and other time they can become blocked with dust and debris which inhibits their ability to draw steam out of the bathroom.
A simple check is to run hot water in your shower for a few minutes and see if the steam is caught and taken away via the fan or does it travel out windows or doors.
A bathroom exhaust fan should be able to perform 15 air changes per hour. To calculate of your exhaust fan is capable you need to calculate your rooms cubic volume, height x width x length and multiple this number by 15. Check with your fans manufacturer to see if it is suitable for your bathroom.
e.g. (4 meters x 4 meters x 2 meters) = 32 x 15 = 480 Meters cubed.
A great way to never forget to use your bathroom exhaust fan is to get it hard wired into your light switch by an electrician.