There's no single schedule for exterior paint. A well-prepared, well-painted house in a mild spot may go ten years or more; a house facing the ocean wind or the afternoon sun may need attention much sooner. What matters is knowing what to look for.
Start with the obvious signs: paint that is peeling, bubbling or flaking; chalky residue that comes off on your hand; cracked caulk around windows and trim; and bare wood showing at corners, sills and the bottoms of siding boards. Any of those means the paint is no longer protecting what's underneath.
Bay Area weather works on a house from several directions. Fog keeps surfaces damp for long stretches, which encourages mildew and slowly breaks down the paint film. Salt air near the coast is harder still on trim, fences and metal. And south- and west-facing walls take the most sun, so they fade and chalk first.
Check the wood itself. If you can push a screwdriver into window sills or trim, there's rot, and it needs to be repaired or replaced before anything else — new paint over rotten wood won't last a season.
Preparation is most of the job. A good exterior paint job starts with washing off dirt and mildew, scraping loose paint, sanding the edges smooth, repairing damaged wood, stucco and caulk, and priming bare spots. Skipping those steps is the most common reason a new paint job fails early, and no paint can make up for it.
Then choose a quality exterior paint suited to the surface, and apply it in dry weather with enough time between coats. Two coats over proper prep will last far longer than one coat over a shortcut.
If you're not sure whether your house is due, we're happy to look at it. Henry's Construction gives free written estimates for interior and exterior painting across San Francisco and the Bay Area — call (415) 654-6558.