Glossary of Terms

The exterior cleaning terms behind every Simple Clean LLC quote, explained clearly and simply.

Know Before You Wash

Power washing has its own language — and knowing the difference between terms like soft washing and pressure washing helps you understand exactly what's happening to your home. Here's what everything actually means, no jargon required.

Power Washing

Per CETA (Cleaning Equipment Trade Association), power washing is chemical-assisted pressure washing — the "power" comes from the soap chemistry, not just the water pressure. Like standard pressure washing, it uses a motor-driven pump to pressurize and accelerate water, but it first applies soaps to emulsify stains and organic matter before rinsing them away, making the wash more effective on driveways, patios, sidewalks, and concrete. See our power washing page.

Soft Washing

Low-pressure (under 100 PSI) application of a sodium-hypochlorite and surfactant solution that kills algae, mold, mildew, and lichen at the spore level — without damaging shingles, paint, screens, or stucco. It's the method we use on every soft washing job, and it's the ARMA-recommended approach for roof cleaning.

Pressure Washing

High-pressure water cleaning (1,500–4,400 PSI) used on hard surfaces like concrete driveways, sidewalks, pavers, and pool decks. Best paired with a surface cleaner for streak-free results — see our pressure washing and flatwork cleaning pages for examples.

Surface Cleaner

A round, shrouded attachment with two rotating spray bars that applies even pressure across a wide concrete or paver surface, eliminating the wand-stripe pattern that single-nozzle pressure washing leaves behind.

Sodium Hypochlorite (SH)

Industrial-grade chlorine bleach diluted with water and a surfactant. It's the active ingredient in roof and house soft washing, and it kills algae and mildew at the root — not just on the surface.

Surfactant

A wetting and clinging agent added to soft-wash mix so the cleaning solution dwells on vertical surfaces (walls, roofs, soffits) long enough to kill organisms before rinsing.

Gloeocapsa Magma

The cyanobacteria responsible for the black streaks running down asphalt-shingle roofs — common here in the humid Mid-Atlantic. Soft washing kills it; pressure washing only rinses the surface, so the streaks return within months. Full breakdown on our roof cleaning page.

Pre-Treatment

Applying cleaning detergent (SH + surfactant) to a surface and letting it dwell 5–15 minutes before rinsing. Letting the chemistry do the work means the wash itself can stay gentle on surfaces and landscaping — a step we walk through on our why choose us page.

Downstream Injector

A venturi attachment that meters cleaning chemical into the low-pressure side of a pressure washer, diluting at roughly 10:1 — the standard delivery method for residential soft washing.

ARMA

The Asphalt Roofing Manufacturers Association — the trade body that publishes the official recommendation for roof cleaning: low-pressure soft washing with sodium hypochlorite, never high-pressure power washing. We follow ARMA guidelines on every roof cleaning job.

PWNA

Power Washers of North America — the industry's leading trade association for training, certification, and best-practice standards. Simple Clean LLC is PWNA-certified, and our owner sits on the PWNA Board of Directors. Learn more on our PWNA page.

Plant Protection

Pre-wetting landscaping and rinsing during a soft-wash job so cleaning runoff is diluted to safe levels before it ever touches roots, leaves, or grass. Required on every job we run.

House Washing

PWNA-certified soft wash cleaning that safely brightens siding, trim, and soffits, removing mold, mildew, and green growth for a fresh, like-new exterior. Every home is evaluated before service so the technique matches the specific siding material — vinyl, stucco, brick, and wood all require different handling to clean effectively without causing damage. It's the standard maintenance we recommend to keep local homes free of mildew shading. See our house washing page.

Roof Streaks

See Gloeocapsa Magma. The dark vertical staining on shingles is a living algae colony, not dirt, and requires biocide treatment — not pressure — to actually remove it.

Deck Cleaning

Soft washing applied to wood or composite decking to lift dirt, mildew, and gray weathering without stripping wood fibers or damaging boards. See our deck cleaning page.

Flatwork Cleaning

Pressure washing applied to patios, driveways, walkways, and other horizontal concrete or paver surfaces to remove algae, moss, and embedded staining. See our flatwork cleaning page.

Frequently Asked Questions

  • What's the actual difference between power washing and pressure washing?

    Both use a motor-driven pump to pressurize water, but power washing adds soap chemistry to break down stains and organic matter before rinsing — that's the "power" in the name. Pressure washing relies on water pressure alone. In practice, we use the method that matches your surface, not a one-size-fits-all approach.

  • Why does Simple Clean use soft washing on my house instead of just pressure washing it?

    High pressure can strip paint, damage siding, or force water behind panels — especially on vinyl, stucco, and wood. Soft washing uses low pressure and the right chemistry to kill algae and mildew at the root without putting your siding at risk, which is why it's our standard for house washing.

  • What's causing the black streaks on my roof, and will you just pressure wash them off?

    Those streaks are Gloeocapsa magma, a living algae colony — not dirt. Pressure washing only rinses the surface, so the streaks come right back within months. We use the ARMA-recommended soft wash method for roof cleaning, which treats the algae at the source.

  • What chemicals do you use, and are they safe for my plants and pets?

    Our soft-wash mix is sodium hypochlorite and a bleach-stable surfactant, applied at a low, controlled dilution. Before we start, we pre-wet all surrounding landscaping so any runoff is diluted to a safe level — a step called plant protection that we follow on every job.

  • How long does the cleaning solution sit on my house before you rinse it off?

    Typically 5 to 15 minutes. That dwell time lets the chemistry break down algae and mildew on its own, so we're not relying on high pressure to force the stain off — which keeps your siding, trim, and roof shingles safe.

  • Will power washing damage my driveway, patio, or pavers?

    Not when it's done right. We pair pressure washing with a surface cleaner — a wide, shrouded attachment that spreads pressure evenly — to avoid the wand-stripe pattern and etching that come from careless technique. See how it applies to your project on our flatwork cleaning page.

  • Are you certified, or is this just something anyone with a pressure washer can do?

    We're certified through PWNA (Power Washers of North America), the industry's leading trade association, and our owner sits on the PWNA Board of Directors. We also follow ARMA's official guidelines for roof cleaning. You can read more on our PWNA page.

  • What's the difference between house washing and deck cleaning?

    House washing is soft washing applied to siding, trim, and soffits. Deck cleaning uses the same gentle approach but is tailored to wood or composite decking, lifting dirt and gray weathering without stripping the wood fibers. Both start with an evaluation of your specific material before we clean.

Meet Ryan McGowan – Owner of Simple Clean LLC Power Washing Services

Ryan McGowan is the owner-operator of Simple Clean LLC Power Washing Services, based in Media, PA, and serving Delaware County, Chester County, and the surrounding Southeastern PA area since 2017. With 20+ years of hands-on experience in exterior cleaning, Ryan personally leads every job — no subcontractors, no rotating crews, just the same trained professional from the first estimate to the final rinse.


Ryan is a PWNA-Certified House Wash Specialist, holding credentials in House Washing, Roof Cleaning, and the Fundamentals of Power Washing through the Power Washers of North America. He also sits on the PWNA Board of Directors and contributes to its Marketing Committee, helping shape higher standards across the exterior cleaning industry — not just following best practices, but helping write them.


Local Certified House Washing Experts Near you

Simple Clean LLC Power Washing Services provides professional house washing across Delaware County and Chester County, Pennsylvania, with a strong focus on Southeastern, PA and the surrounding suburbs. If you're searching for house washing near me or a reliable house wash service near me, our team delivers certified, low-pressure results that protect your siding, trim, and soffits for both residential and commercial properties.


We also carry full insurance and operate as an owner-operated company, which means the person responsible for the work is the person doing the work. No subcontractors, no unfamiliar crews showing up unannounced, and no passing the buck if something isn't right. When you hire Simple Clean LLC for house washing in Southeastern PA, you're getting a contractor who shows up, does the job correctly, and stands behind the results — with the certification, the insurance, and the track record to back it up.