Tamarama’s slopes face the ocean, but the gully floor and the walls that face into it get little sun. Tamarama Park sits along the bottom, the gully channels moist air off the sea, and shade from the slopes and trees keeps surfaces damp for long periods.
Elevations facing into the gully, and anything near the bottom of it, behave differently from the sunny, salt-washed faces above.
What the data says
The Bureau of Meteorology’s long-term Sydney record shows average 9am humidity of 74 percent from February through June. March has the most rain days of the year. In a shaded gully, surfaces stay wet long after the rain stops.
What grows
Green algae on render, paint and fences. Black mould and lichen on sandstone and concrete. Moss on paths, steps and roofs, wherever the sun never reaches. Mildew under eaves and balconies where air is still. More: the green film on walls.
Why washing alone does not work
Water and pressure remove the visible layer of growth but leave the organism in the surface. It regrows in months. Pressure also damages render, paint and timber and opens them to faster regrowth.
Soft washing kills the growth with a biocide applied at low pressure. The dead material releases and weathers away over weeks, and regrowth takes much longer. More: how we soft wash and removing mould from render.
Slippery steps and paths
In a steep suburb of stairs, growth on paths and steps is a real fall risk. Clean them regularly and consider slip resistance when choosing sealers. More: slip resistance and moss on concrete.
Gardens and runoff
Soft wash chemistry burns plants and must not reach the ocean. Pre-wet plants, cover what can be covered, rinse afterwards, and direct runoff to soil rather than stormwater. More: pets, ponds and gardens on soft wash day.
Fix the water source
If a wall is damp from a leaking gutter, a garden bed against it, or a retaining wall without drainage, it will regrow regardless of cleaning. Look for growth concentrated at the base of walls or below gutters. More: retaining walls and drainage.
Timing
Soft wash shaded elevations in late autumn or spring, on calm days. They need cleaning more often than sunny ones, often yearly.
What owners can do
Brush off visible growth on paths and steps regularly with a stiff broom when dry. Keep gutters clear so roofs drain properly. Trim plants away from walls to let air move. Keep mulch and soil off the base of walls. Ventilate sub-floors and storage spaces.
Do not mix your own bleach solutions for walls and paths. Home-mixed bleach is inconsistent in strength, burns plants, runs into stormwater, and often leaves streaks or patches on paint and render. More: moss killers for roofs and pavers.
See the Tamarama maintenance calendar and our mould removal service.
