Painted stucco is the most common exterior in Miami and one of the easiest to damage. The damage is almost always the same story: someone pressure washed it. Here is why that is the wrong tool, and what to use instead.
Why pressure washing wrecks stucco
Stucco is porous by design, and paint sits on top of that porous surface. Point a high-pressure tip at it and two things happen. Water gets forced into the wall, where it has no business being, and the finish can blow out in sections. On painted stucco, pressure lifts the paint outright, leaving bare, patchy spots that then need repainting.
So the cheap pressure wash becomes a paint job. That is not a saving.
How soft washing cleans it safely
Soft washing runs at about garden-hose pressure and lets a cleaning solution do the work. The solution kills the algae and mildew growing on the surface, and the low-pressure rinse carries it away. Sound paint is not disturbed, water is not driven into the wall, and the finish stays intact. The walls come back clean and stay clean, because the growth was killed rather than smeared around.
How to spot trouble before it starts
Ask what pressure they will use on the walls. If the answer is the same setup they use on the driveway, your stucco is about to take damage. A real exterior wash soft washes the walls and soffits and only pressure washes the hard surfaces like the driveway and walkway. That is how we approach stucco, matched to the surface every time.
Common Questions
Can you pressure wash stucco?
You should not. Stucco is porous and high pressure forces water into the wall and can blow out sections of finish or strip paint. Stucco gets soft washed at low pressure instead.
Will cleaning remove paint from my stucco?
Not with soft washing. Soft washing uses garden-hose pressure and a cleaning solution, so it lifts algae and mildew without disturbing sound paint. Pressure washing is what strips paint.
Why are the north and shaded walls always the dirtiest?
Those walls stay damp longest and get the least sun, which is ideal for algae and mildew. They green up first and worst, and they are the main reason a house looks dirty from the street.