Pressure Washing and Soft Washing in Metro Detroit

Pressure washing removes dirt with the force of the water. Soft washing removes it with a cleaner put on at garden-hose pressure and then rinsed off. Soft washing is right for anything water could get behind or damage: siding, soffits, fascia, painted surfaces and roofs. Pressure is right for concrete, pavers and masonry.

The simple test is whether the dirt is alive. Green and black growth on siding is algae, mildew and lichen rooted into the surface. Force takes off the top layer and leaves the roots, so it grows back within a season. A cleaner left on long enough kills it, and the surface stays clean much longer. Road film and tire marks on a driveway aren't alive, and pressure takes them off.

If someone quotes your whole house at one pressure setting, that tells you how the job will go.

Four things do most of the damage here, each in its season: road salt and brine in winter, tree pollen in April and May, algae and mildew on the shaded sides through a humid summer, and leaf stains from wet leaves left on concrete and decks in October and November.

Salt is the one people underestimate, because it doesn't look like dirt. It coats the lower few feet of siding, the garage doors, the front steps and the end of the driveway, and it stays there. On concrete it does real damage: salt speeds up the freeze-thaw cycle inside the slab, and that causes the flaking, pitted surface you see on Michigan driveways and porch steps after eight or ten years. Washing the salt off each spring helps the concrete last.

Leaf stains are the seasonal one to plan around. Wet maple and oak leaves left on a concrete patio or a wood deck for a few weeks leave a brown stain that gets harder to remove the longer it sits. If leaves piled up on your patio last fall, book the wash for spring.

Most homes in these subdivisions have vinyl siding, or vinyl and brick, and vinyl is where pressure does the most damage. The panels hang loose so they can expand and contract, so high-pressure water aimed upward goes right behind them. Once water gets into the wall, it's slow to dry out.

Aluminum siding on older Livonia and Farmington Hills homes can fail a different way. The paint chalks with age, and scrubbing it hard pulls the chalky layer off unevenly and leaves it patchy. On any aluminum house we test a low spot first and tell you what the finish will look like.

Brick and painted brick can take more pressure than vinyl, though less than people think, and old mortar sets the limit. On older homes near downtown Northville and around Kellogg Park in Plymouth, the mortar is soft lime mortar that high pressure will wash out of the joints. Cedar gets low pressure, always with the grain, because pressure across the grain raises the fibers and leaves the wood fuzzy when it dries.

A hand wand cleans a narrow strip at high pressure, and the passes never overlap evenly. That's the zebra striping you see on plenty of driveways around here, and it doesn't wash out, because it's a difference in texture etched into the concrete.

The right tool is a surface cleaner: a covered spinning bar with two nozzles that keeps the pressure even across the whole width. We run it over the open concrete, then clean the edges, joints and steps by hand at lower pressure. Wand marks come from skipping the surface cleaner.

Sometimes we'll tell you to skip it. Concrete that's already salt-scaled, with the top layer flaking and the stones starting to show, is damaged at the surface. Pressure washing it makes the flaking worse and leaves a rougher driveway. If you still want it cleaned, we'll do it at low pressure and tell you what to expect first.

We clean wood decks at low pressure with a cleaner made for wood, always with the grain. The goal is to lift the grey layer and the algae without raising the grain, because fuzzy wood takes stain unevenly and splinters underfoot. If you plan to re-stain, wash in spring and let the boards dry out properly first.

Composite decking gets a soft wash. Most manufacturers void the warranty above a fairly low pressure, and composite scratches more easily than people expect. Paver patios need care too, because pressure aimed into the joints blows out the sand that holds the pavers in place. We clean pavers at reduced pressure and tell you if the joints need re-sanding.

April through November is the season. The cleaner needs warmth, and the equipment and the rinse water freeze in the cold. It's shorter than most people plan for, so the good dates go early.

Two times are worth aiming for. Late April through May clears the winter salt off the siding, the concrete and the garage doors, right before you start using the yard. Late September through October catches the summer growth and gets the deck clean before the leaves pile up. If you're also booking window cleaning or gutter cleaning, the order matters: house first, then gutters, then windows, so nothing gets dirty again.

Each surface is priced separately. For the house, it's the size, the height and how much growth there is. For concrete, it's square footage and condition, since oil, rust and leaf stains need pre-treatment first. For decks, it's the size and how weathered the boards are.