What makes a coating system coastal
The phrase gets used loosely, so it is worth being specific. A coastal system is not simply a more expensive topcoat. It is the whole sequence: removing chloride from the surface, treating corrosion at every metal point back to sound material, using primers formulated for salt exposure, and choosing a topcoat flexible enough to keep moving with the substrate through summer heat and winter damp. Change any one of those for a cheaper option and the system performs like a standard repaint, because the weakest layer sets the life of the job.
Why the wash-down is not optional
Salt is hygroscopic, meaning it pulls water out of the air and holds it against the surface. Paint applied over it traps that moisture underneath. This is the single most common reason coastal repaints blister early, and it is entirely preventable.
Where the money is best spent
Not every wall on a Merewether home needs the full system. Exposure varies enormously between an east-facing wall and a sheltered courtyard elevation. We specify by exposure so the budget goes where the weather actually is.
