Driveway and Patio Cleaning in McHenry, IL

Reading the stains: salt, rust, oil and algae are different problems

White crust at the edges and along joints is usually salt or efflorescence, mineral deposits pulled to the surface by moisture. Orange freckles are rust, from metal furniture, tools or iron in the water. Dark patches by the garage are oil. Green or black patches in the shade are growth, not dirt.

Every stain answers to its own approach. Salt and algae wash off fairly well. Rust can lighten but sometimes leaves a ghost. Old oil that has soaked into concrete may fade without disappearing. Rob will tell you which stains look removable from your photo. White Powder, Rust Stains and Salt Damage on Concrete: What Is It and What Helps? breaks down the chemistry in more detail.

• White crust is salt or efflorescence
• Orange freckles are rust
• Dark patches by the garage are oil
• Shade-grown green or black is algae

McHenry driveways: the plow edge and the garage apron

Most winter damage collects at two spots. The edge closest to the street takes plow spray and salt, and the apron at the garage door takes meltwater dripping off cars. Both stay wet longer, so they stain most. Wide driveways on corner lots take more of it.

Rob cleans the whole slab evenly rather than only the stained areas, because spot cleaning can leave a clean patch that looks odd against the dingy surround. He also checks joints and cracks, since water gets into those and refreezes. A cleaned driveway is easier to inspect, and he will mention cracks that deserve a patch or sealer from a concrete contractor.

Patios and pavers: gentler than a driveway

Paver patios rely on sand packed between stones, and hard spray can empty those joints. Weeds grow in them, algae coats the surface under trees, and ants sometimes nest beneath. Rob cleans pavers with controlled pressure, keeps the stream from blasting the joints, and tells you when new sand is needed.

Stamped concrete and colored slabs have sealers that cleaning can dull or strip. If your patio was sealed, mention it. Resealing after cleaning is often worth discussing, since sealer keeps salt and stains from soaking in. Patios attached to wood decks or siding can be done along with deck washing and staining and house washing in one visit.

Shade, damp and the river-town algae problem

Concrete near trees, under roof drip lines or on the north side of a house stays damp. Algae grows in that film, turns slippery, and is a real hazard on steps and walks in wet weather or when it freezes. The City of McHenry has plenty of mature trees and plenty of humidity from the Fox River valley.

Cleaning helps, but the cause keeps working. Trimming branches that block sun, fixing a gutter that spills onto the walk and sweeping off leaves all slow regrowth. Rob can point out these small fixes when he sees a photo or visits.

What cleaning will not fix on concrete

Cleaning removes dirt and growth. It does not repair cracks, heaved slabs, scaling from freeze-thaw, or deep staining that has chemically changed the concrete. A heavily scaled surface may look worse after cleaning, since the loose top layer comes away.

Rob prefers to say this early rather than let you pay for a result that disappoints. If a slab needs resurfacing or replacement, a concrete contractor is the right call. If it is sound but tired, a cleaning can make a large visible difference. For general guidance on how pressure and chemistry fit together, Soft Washing vs Pressure Washing: Which Does Your Surface Need? is a good start.

Driveway & Patio Cleaning through the year in McHenry