Over time discolorations and stains may occur due to normal usage despite the best efforts of residents to keep it clean. These cannot be cleaned through regular methods and require more aggressive cleaning methods, such as power washers, sweepers or hand scrubbing with a release agent.
Given the disruption this would cause if everybody cleaned their own balconies with such methods, it is best that a strata periodically organize a cleaning for all residents. This also ensures that any runoff from the balcony washing is properly managed cleaned up properly and does not affect the appearance of units below.
Exposed balcony and patios generally should be cleaned once every two years or more, depending on their surface composition. These generally see greater weathering and the benefits are more apparent.
If the balcony is part of the gutter system, then it should be every year, since blockages may cause overflows and potential damage to the building’s structure. For covered balconies, the cleaning interval can be extended out further: every three or more years.