Best exterior paint for Miami: humidity, salt air and sun

South Florida is one of the harshest coating environments in the country. Direct UV nearly year-round, relative humidity that rarely drops, wind-driven rain, and salt aerosol that travels miles inland. A paint system that performs beautifully in Atlanta can chalk, blister or grow mildew here within two seasons.

What actually destroys exterior paint here

• UV degradation. Sunlight breaks down binders and pigments, leaving a chalky surface that no longer sheds water.
• Moisture from behind. Stucco and CBS walls hold water. If the coating cannot breathe, vapor pushes the film off the wall as blisters.
• Mildew. Warm, damp shaded elevations are ideal for growth; without a mildewcide package it returns within months.
• Salt. Coastal properties collect airborne chloride that attacks substrates and any exposed metal fastener or trim.
• Thermal movement. Daily expansion and contraction opens hairline cracks in stucco that a rigid film cannot bridge.

The coating choices that hold up

Elastomeric is not automatically the right answer. It is excellent over cracked stucco, but on a wall with trapped moisture and no drainage detail it can make blistering worse. The system should be chosen after the wall is inspected — never from a catalogue.

Prep is the coating's life expectancy

1. 01Pressure wash and let the substrate dry fully — in Miami that can mean 24 to 48 hours.
2. 02Kill mildew with an appropriate cleaning solution, not just water pressure.
3. 03Patch cracks and spalls, then cure the patch before priming.
4. 04Recaulk every window, door and dissimilar-material joint with a high-grade elastomeric sealant.
5. 05Prime bare, patched or chalky areas. Skipping spot priming is the most common cause of premature failure.
6. 06Apply two full coats at the manufacturer's wet-film thickness, not thinned to stretch coverage.

Colour choices that age well in the light here

Miami light is bright and slightly warm, which pushes cool greys toward blue and makes stark whites glare. Off-whites with a soft warm base, sand tones, muted terracotta and deep coastal blues hold their character. Very dark, saturated colours absorb heat, move more, and fade faster on south and west elevations — if you want drama, keep it on protected or accent areas.