How salt actually gets to a shutter
Salt doesn't need spray to travel. Onshore breezes carry a fine aerosol of it well inland, and it settles on every surface that doesn't get rinsed by rain, which includes every indoor surface near an openable window. Corrosion science formalises what lakeside owners already know: Australia's atmospheric corrosivity standard, AS 4312, maps corrosion rates that fall away sharply with distance from the water, which is exactly the gradient we spec against. In practice we treat the city as three bands: on the water, east of the highway, and the hills.
The louvres themselves are only half the story. A shutter fails at its metal first: hinges, tilt gear, screws. The best material decision in the world is undone by plated steel hardware a hundred metres from the channel at Swansea, which is why our lakeside specifications talk about stainless and coated hardware as loudly as blades.
The three materials, straight
| Material | Where it wins | Where it loses | Salt verdict |
|---|---|---|---|
| Aluminium | Outdoor and the most exposed faces: powder-coated, UV-stable, unbothered by spray. The default outside and the safe call anywhere near the water. | Cooler to the touch and eye than timber; a hard, precise look that suits modern joinery better than a federation sill. | The benchmark. Rinse it occasionally and it simply keeps going. |
| PVC (often aluminium-cored) | Living rooms and every wet room. Waterproof, wipe-down, painted-timber looks without timber's worries; the core keeps wide blades stiff. | Very wide spans want the aluminium core; deep custom colours are more limited than paint-anything timber. | Excellent. The louvre shrugs; choose the hardware as carefully as ever. |
| Basswood timber | The hills' living rooms and bedrooms: light, stable, warm, paintable to any colour, the classic look brick homes were built for. | Persistent damp and heavy salt. Finish maintenance is real on exposed faces; coastal weather ages paint faster than postcards suggest. | Fine in the hills and protected rooms; near the water it needs honesty and upkeep, and we'll say so at the measure. |
By the bands
- On the water
Aluminium outside, PVC or aluminium inside, stainless hardware throughout, and a wipe-down rhythm. The care checklist is written for exactly these homes.
- East of the highway
PVC leads inside; timber survives in protected spots but gets a caveat. The salt arrives slower here, not never.
- The hills
Basswood's home ground. Charlestown and Cardiff living rooms are where timber's warmth is worth having and keeps for decades. PVC still owns the bathrooms.
Questions we get on this
Is timber ever right near the water?
Sometimes: a protected courtyard window, a southern face out of the weather, an owner who genuinely wants the material and accepts the upkeep. What we won't do is sell it there without the caveat.
Which brands do you carry?
We describe materials generically on this site on purpose: ranges change, and honest advice shouldn't be a catalogue. At your measure you'll see the actual samples and systems we'd use for your windows, in your light.
Does aluminium look industrial?
Not any more. Modern powder-coated aluminium louvres read as painted shutters from a metre away; hold a sample against a PVC blade at your measure and judge with your own eyes.
Reference
- AS 4312, Atmospheric corrosivity zones in Australia: the standard behind the "distance from the salt" bands, mapping how corrosion severity falls away from the coast.
- YourHome: Materials, the Australian Government's guide to durable material selection for Australian conditions.