What salt air actually does to a Merewether exterior
Salt does not attack the paint film first. It lands on the surface, draws moisture out of the air, and holds it against the substrate long after the wall looks dry. On timber that means swelling and movement under the coating. On metal it means corrosion starting at fixings, fascia, and gutter lines while the flat surfaces still look fine. That is why a Merewether repaint that skips the wash-down fails early no matter how good the topcoat was. We take the salt off first, then deal with what it has already started.
The elevations that fail first
On the streets running down toward the beach it is almost always the eastern and south-eastern faces, plus anything above the roofline catching wind-driven spray. We look hardest at those and specify accordingly rather than spreading the same system evenly over a house that is not evenly exposed.
Metal points
Fixings, brackets, fascia, and flashings corrode long before the walls do this close to the water. We treat existing rust back and prime for coastal metal instead of coating over it, because rust under a fresh topcoat keeps going.
