Should You Pressure Wash Before Painting?

Yes, and in Florida it is the single biggest factor in how long the new paint lasts. Paint applied over algae, mildew or chalking bonds to the contamination rather than the surface, and begins peeling within a couple of years. Wash first, let the surface dry fully, which usually means two to three dry days, then paint. Most exterior paint warranties require proper surface preparation to remain valid.

Why paint fails early here

Almost every premature exterior paint failure in Northeast Florida traces back to what was underneath. Not the paint, not the application, the preparation.

Algae and mildew are living growth. Painting over them seals them in with a moisture supply and no light, and they continue working away at the substrate while the film above loses adhesion.

Chalking is the other one. Older paint degrades into a fine powder on the surface, and new paint applied over chalk bonds to loose powder rather than to anything solid. It looks perfect for a year, then sheets off.

How long to wait before painting

Two to three dry days is a sensible minimum, longer for stucco or any masonry, which holds water far longer than it looks.

Shaded elevations and north-facing walls need more time than the sunny sides, and it is the shaded walls people tend to misjudge.

A moisture meter is the honest answer if the schedule is tight. Painters who own one will use it, and it is worth asking whether yours does.

Coordinating the two jobs

Tell us you are painting when you book. It changes the approach slightly, because the goal shifts from making the surface look clean to making it accept a coating.

That usually means more attention to chalking and to any failing paint edges, and a final rinse that leaves no cleaning residue behind, since residue affects adhesion just as contamination does.

Booking the wash for early in the week and the painting for later in the same week generally works, with weather allowing. Request a quote or call (904) 506-7656 and mention the painting date.

Frequently asked questions

Can the painters just wash it themselves?

Some do, and some give it a quick rinse and call it preparation. Ask specifically whether they are washing with a cleaning solution or only rinsing, because the difference is what determines whether mildew survives under the new coat.

Does this apply to a repaint of trim only?

Yes, and trim is often worse, because it is the part that stays shaded and damp longest.

What if I painted over mildew already?

It will usually show through as dark patches within a year or two. There is no fix short of stripping the affected areas and starting again, which is why the preparation matters.

Related reading

• Gutter Cleaning in Florida: How Often and Why It Matters
• Pressure Washing in Nocatee, FL: What Homeowners Should Know

Get a free quote

H2O Pressure Washing serves Saint Johns and the wider St. Johns County area. For a free, fixed-price quote, tell us about your property or call (904) 506-7656.