What the salt actually does
From Mouille Point to Hout Bay, the air carries salt, and salt does three things to a garage door. It corrodes the copper tracks on the motor's circuit board until a connection fails, which is why a motor repair here so often finds a board rather than a gear. It rusts the lifting cables from the inside, so a cable in Sea Point can look sound and be half its strength, and it eats the bottom panel of a steel sectional from the bottom edge up until the paint bubbles and then holes. A door that would last twenty years in the suburbs lasts eight on the seafront if it is fitted and serviced like a suburban door.
It does not have to. A coastal door specified for the coast — stainless hinges, rollers and cables, a sealed panel edge, a coating rated for the exposure, and a service interval that catches the cable before it fails — lasts as long as any other. The difference is almost entirely in the specification, and it is the conversation had on every visit along this coast.
Apartments, basements and the body corporate
Much of the Seaboard lives in blocks, and the garage door is the basement roller shutter or sectional that the whole building drives through. When it fails, it fails for everyone, and the call comes from the managing agent with a hundred residents' cars behind it. Those are treated as an emergency at any hour — a basement door stuck shut at seven in the morning is a building that cannot get to work — and the repair is scheduled around the residents once the door is secured.
The Green Point and Three Anchor Bay blocks run on commercial-grade motors with their own parts and their own failure modes, and a technician who knows that a particular brand's receiver goes first in salt air is worth more than one who treats it as a house door.
The big houses, and the wind
Camps Bay, Clifton, Bantry Bay and Fresnaye are large houses on steep stands, with double and triple garages, doors that face the sea and the wind that comes off it, and motors that are asked to do a lot. The doors here are worth specifying properly and servicing on a schedule, because a spring or a set of cables caught on a service visit is a fraction of what the same failure costs on a Saturday night with the house open to Victoria Road.
Further along, Bakoven and Llandudno are more exposed still, and a roll-up in its guides handles the wind better than a sectional on the most open stands. All of it is worked from the same coastal routes, and the vans carry the stainless hardware this side of the mountain needs.