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Pressure Washing In Lawrenceville
Beautifying residential and commercial establishments since 1984
Diagnosing Algae, Mold, and Pollen Buildup
Those black streaks on your siding are not dirt. They are algae, and they respond to different treatment than mold or pollen. Most exteriors have two or three of these layered together, which is why the surface gets inspected before anything is sprayed.
The dark, almost sooty streaks running down siding and shingles are a type of algae called Gloeocapsa magma, which feeds on the limestone filler in many roofing and siding materials. It shows up first where the house gets the least direct sun.
Green fuzzy patches are a different algae, one that likes moisture and shade. It grows heaviest on north-facing walls, under deck overhangs, and anywhere overflowing gutters keep a surface wet too long.
Mold looks different again — darker, almost black or gray, sitting in corners and under eaves that stay damp for days after rain. Press a cloth against it; a dark smear means mold rather than surface grime.
Then there is pollen. Every spring Gwinnett County gets a yellow-green film that settles into the pores of siding and concrete. On its own it is harmless, but it traps moisture against the surface, which feeds whatever algae and mold are already growing there.
Choosing Between High-Pressure and Soft Washing
Not every surface can take the same treatment. Concrete usually handles a strong blast. Siding, brick, and roofing cannot, and we regularly see the results when someone rents a machine, cranks it up, and strips paint or mortar off a wall.
Many Lawrenceville homes from the ’80s and ’90s have vinyl siding and brick veneer. High pressure can crack vinyl or force water behind the panels, so we drop the PSI and use a soft wash instead, letting the cleaning solution lift the growth rather than hammering the material.
- Concrete driveways and sidewalks — high pressure and direct spray handle years of grime and tire marks
- Vinyl and wood siding — soft washing with low PSI and a cleaning solution avoids cracking or gouging
- Brick and mortar — moderate pressure and a wide fan tip protect old mortar joints
- Roof shingles — soft washing avoids the granule loss that shortens a roof’s life
- Wood decks and fences — low pressure and careful angle control keep the grain from splintering
Older mortar, soft wood, and painted trim all call for restraint rather than force. The surface tells us what it needs before the machine goes on.
When Pressure Washing Isn't the Right Fix
Pressure washing is right for a sound surface covered in dirt, grime, or mildew. A damaged, cracked, or peeling surface needs repair or repainting before water touches it.
- Paint already peeling or bubbling — that needs prep and repainting, not water pressure
- Cracked or crumbling stucco, mortar, or brick joints — repair first, or pressure forces water deeper
- Dark stains returning within weeks — usually a moisture or drainage problem rather than dirt
- Loose or rotted wood siding and trim — washing can do more damage
- Roofs — standard pressure washing can lift shingles, so these get soft washed
Older homes near downtown are the common case. Original wood trim there has taken decades of sun and moisture, and washing peeling paint strips more paint and soaks the bare wood underneath, which then has to dry before anything can be repainted. And if your gutters overflow onto the siding every time it rains, washing will not keep the stain away. Fix the gutter first.
What to Expect During a Professional Visit
You do not need to do much before we show up. We walk the property first, since brick, siding, concrete, and wood decking all need different methods, and many older homes near downtown still have original hardboard siding that scars under too much pressure.
- Walk the exterior and flag fragile areas, including old caulking and loose gutters
- Cover outdoor outlets, plants, and light fixtures near the washing area
- Apply a cleaning solution first to loosen mildew and grime before rinsing
- Wash from the top down, with lower pressure on siding and higher pressure on concrete
- Rinse thoroughly and check the runoff for remaining soap or debris
- Walk the property with you afterward and point out anything we noticed, like rotted trim or peeling paint
Most jobs take a few hours, longer when mildew has built up over several humid summers. If we spot siding damage or peeling paint during the walk-through, we will tell you plainly — pressure washing alone will not fix those, and exterior painting is a separate conversation.
Seasonal Timing for the Piedmont Climate
Timing matters more here than most people think. Lawrenceville sits in the Piedmont, with thick spring pollen, heavy summer humidity, and red clay that storms splash onto siding. Each leaves a different kind of grime, with a different window for longer-lasting results.
From late March into April, pine pollen coats driveways, siding, and fences. Wash too early and it is back within a week, so we usually suggest waiting until the heaviest drop settles and then cleaning once.
- Spring, after pollen drop — good for driveways and siding under yellow-green dust
- Summer, after heavy rain — good for clearing red clay splash-back near foundations
- Fall, before leaves pile up — keeps gutters and walkways from staining over winter
- Winter, mild days only — freezing temperatures crack hoses and stress older mortar joints
Humidity is the other factor. Summers here stay damp for weeks at a stretch, feeding algae on the shaded, north-facing walls homeowners call us about. We do not pick a season off the calendar alone; we look at the house, its shade, and the last sustained dry stretch.
Frequently Asked Questions
Most homes here need a wash once a year, though shaded and north-facing walls may need it sooner. Humid summers feed algae and mold fast, especially under deck overhangs or near overflowing gutters. Dark streaks or green patches returning within a few months mean the surface needs attention again.
Pressure washing uses high PSI and suits tough surfaces like concrete. Soft washing uses lower pressure and a cleaning solution, which is safer for vinyl siding, brick, wood, and roof shingles. We match the method to the surface rather than the other way around.
Yes, if the wrong pressure is used on the wrong surface. High pressure can strip paint, crack vinyl, or knock granules off shingles. Older wood trim and hardboard siding scar easily, which is why we inspect for loose paint, cracked mortar, and fragile trim before the machine goes on.
A full walk-around before any water touches the house. We check siding, brick, concrete, and decking for fragile spots, cover nearby outlets and plants, apply a cleaning solution to loosen grime, wash top down, and rinse thoroughly. Most jobs take a few hours.
Those streaks are algae, not dirt, and they return quickly if the underlying cause is not fixed. Overflowing gutters are a common culprit, and shaded north-facing walls stay damp longer. Stains reappearing within weeks usually point to a drainage problem rather than dirt.