Concrete & Sidewalk Cleaning

The problem

Concrete under tree cover turns dark green or black. That's not dirt, it's algae and organic film feeding on the moisture the shade holds in, and it's also slippery when wet — which makes a shaded front walkway a genuine trip hazard, not just an appearance problem.

Why concrete under trees goes black

Shade keeps the surface damp longer, and concrete is porous enough to hold that moisture. Add organic debris from overhead and you have ideal conditions for algae. It grows back on the same schedule the shade allows, which is why the north side of a walkway always looks worse than the south.

What we clean

Front walkways, side paths, sidewalks, entry steps, pool surrounds, garage aprons and general flatwork. We handle the transitions and edges properly rather than cleaning the middle and leaving a dirty border.

Our method

Pre-treatment on organic growth so it's killed rather than just knocked back, then rotary surface cleaning for even coverage, then detail work with a wand along edges, steps and anywhere the surface cleaner can't reach. Rinse-down of adjacent landscaping afterward.

Efflorescence and what won't come out

The chalky white bloom that shows up on concrete is efflorescence — mineral salts moving through the slab. It can be reduced but it recurs because the cause is moisture inside the concrete, not on it. We'll be straight with you about that rather than promising it's gone for good.