By Naldo Neto, IRATA Level 3 and licensed painter · Updated October 2026 · 1 min read
Key takeaways
- Salt air speeds up corrosion in concrete, metal and paint.
- Coastal buildings need more frequent washing, inspection and repainting.
- Concrete balconies and slab edges are the most common failure points.
- Protective coatings and early repairs extend the time between major works.
From Cronulla to Manly, Sydney's coastal suburbs are some of the most desirable places to live. They are also some of the hardest places for a building to age well. Salt, wind, moisture and strong sun work on façades all year round.
How salt attacks a building
Sea spray carries chloride salts inland on the wind, often several hundred metres or more depending on exposure. Salt settles on walls, balconies and window frames, and every time it rains or dew forms, some of it soaks into the surface.
- Concrete: chlorides travel through the concrete to the steel reinforcement and break down its protection, leading to corrosion and concrete cancer.
- Render and masonry: salts crystallise in the pores as the wall dries, which can cause flaking and powdering.
- Paint: salt and UV break coatings down faster, causing chalking, fading and loss of adhesion.
- Metal: balustrades, fixings and window frames corrode, staining the wall below.
- Sealant: UV and movement harden joints faster, opening paths for water.
Warning signs on coastal buildings
- Rust stains below balconies and fixings
- Cracks along balcony edges
- Paint that leaves white powder on your hand
- Flaking or crumbling render near ground level and on exposed elevations
- Cracked or gappy sealant around windows
How to protect a coastal building
- Wash regularly. Rinsing salt and grime off the façade every year or two slows coating breakdown.
- Use a coating system suited to marine exposure. Anti-carbonation and elastomeric systems protect concrete and bridge fine cracks better than standard paint.
- Repair defects early. Small spalls and cracks are cheap to fix; widespread corrosion is not.
- Replace sealant before it fails. Coastal joints often need replacing sooner than inland ones.
- Inspect every few years. A close façade inspection finds problems before residents do.
We work on coastal buildings across the Eastern Suburbs, Northern Beaches, Sutherland Shire and Wollongong. See our protective coatings service.
Sources and further reading
- IRATA International: rope access training and the International Code of Practice
- SafeWork NSW: managing the risk of falls at workplaces
- Standards Australia: AS/NZS 4488, AS/NZS 5532 and AS/NZS 1891.4
- NSW licence check: verify any contractor's licence
Questions
How far inland does salt affect buildings?
It depends on wind, exposure and terrain, but buildings within a few hundred metres of the ocean or harbour are most affected, and effects can reach further on exposed sites.
How often should coastal buildings be washed?
Every one to two years is a good rule for exposed coastal buildings, more often for very exposed elevations.
About the authorNaldo Neto leads Tactical Height Solutions. He is an IRATA Level 3 rope access technician and licensed painter with a background in rendering and remedial work on Sydney buildings. More about Naldo.