The salt exposure timeline
Merewether's whole garage-door story is geography: how far your street sits from the surf, and how high. Pick your position between the break and the ridge, tell it roughly how old the door is, and get a straight read on how hard the salt is working and when a service check makes sense. It won't diagnose your door and it won't price anything; that takes eyes on hardware.
Step 1 · where do you sit? (tap the section or pick a band)
The bars are an indicative picture of how hard the salt works in your band as hardware ages, not a measurement of your actual door. Only an on-site look can tell you what your hardware is really doing.
Same read, no clicking
| Band | Where that is | What the salt is doing | A sensible rhythm |
|---|---|---|---|
| Beach rows | Bar Beach front streets, beachside Merewether | Wave aerosol lands on hardware most days; zinc-plated springs, cables and fixings corrode fastest here and fail suddenly rather than gradually. | A service check about once a year, and marine-grade parts at every replacement. |
| The flat | Merewether proper, the first ridge (elevation about 16 m) | Within about a kilometre and a half of the surf: solidly inside the salt band, one step gentler than the front rows, same sudden failure mode. | A service check every year or so. |
| Junction side | The Junction, the Cooks Hill edge | A little sheltered by distance and terrain, but still coastal air, and this side carries some of the oldest hardware in the patch. | Every couple of years, sooner for doors past 15 years old. |
| The Heights | Merewether Heights ridge streets | Further from the spray but square in the wind, with under-house garages and steep driveways adding mechanical load and geometry problems of their own. | Every couple of years, and get door type right when replacing. |
How this works, and what it deliberately won't do
The bands follow the logic of AS 4312, Australia's atmospheric-corrosivity standard: salt influence from an open surf coast generally reaches about a kilometre inland, and further where the terrain is flat and the wind is onshore, which is exactly Merewether's arrangement. Distance from the break and elevation are the two variables that matter, and they are the two the tool reads.
What it won't do: assign an official corrosivity category to your address (that's a site assessment, not a postcode lookup), diagnose a fault from a symptom list, or estimate a price. It ends where honest general guidance ends, at "here's when a look makes sense".