The Stripes Pressure Can't Touch
If you've ever looked up at your gutters and seen dark vertical lines running down the white aluminum face, you're seeing what the industry calls "tiger stripes." They're one of the most common cosmetic issues with aluminum gutters in South Florida and one of the least understood. Most homeowners think they're dirt and that a quick pressure wash will lift them. Most homeowners are wrong, and most pressure washers don't know how to fix them either.
Tiger stripes are a chemical issue, not a dirt issue. They're a combination of three things: asphalt residue from your shingle roof that runs off in rain and stains the gutter face, oxidation of the aluminum itself where the rainwater contacts it, and electrochemical staining at the drip edge where each rain event leaves a faint mineral line. Over years, these three combine into the dark vertical streaks you see every time you look up. Pressure washing doesn't lift them because there's nothing to mechanically blast away — the staining is part of the surface chemistry now.
The Right Chemistry
The fix is a gutter-specific brightener formulated for exactly this kind of stain. It's a mild acid-based chemistry that breaks down the asphalt residue and lifts the oxidation layer, restoring the aluminum (or the powder-coated paint over the aluminum) to its original color. Applied correctly, it's safe for the gutter, safe for the paint, safe for nearby plants and surfaces below, and produces dramatic results — usually visible within minutes of application.
Our Brightening Process
- Perimeter pre-rinse of all landscaping below the gutter line
- Brightener applied with a brush or low-pressure sprayer to the visible gutter face
- Dwell time of 5-10 minutes (longer on heavy staining)
- Light agitation with a soft brush where staining is severe
- Clean-water rinse from the top down
- Post-rinse of all landscaping below the gutter line
- Visual inspection and before-and-after video documentation
What's Safe and What's Not
The brightener chemistry is safe for aluminum, powder-coated paint, factory-finished colored gutters, and standard fascia. It's not aggressive enough to damage these materials when applied correctly. It is mild acid, so we control runoff carefully — pre-rinse and post-rinse all landscaping, contain runoff so it doesn't pool against plant beds, and do final neutralization rinses. We've done extensive gutter brightening alongside prized landscaping, mature shrubs, and freshly laid sod without issue.
How Long the Results Last
Properly brightened gutters typically stay clean for 18-24 months before any new staining is visible. The underlying causes — asphalt runoff, oxidation, drip edge mineral staining — keep happening, so eventually the stripes will start to come back. Homes with heavy rain exposure (open lots, no tree cover blocking direct rain on the gutter face) tend to see staining return faster. Homes with shaded gutters can go longer.
Bundle With House Wash & Interior Gutters
Gutter brightening is almost always bundled with one or more other services. Most commonly it's combined with a full house soft-wash and interior gutter cleaning — we're already up at the gutter line, so doing all three at once is significantly more cost-effective than separate visits. The result is a complete exterior refresh: brighter house, cleared gutters, brightened gutter face, and a visually consistent appearance.
Frequently Asked Questions
"Tiger stripes" — a combination of asphalt shingle runoff, aluminum oxidation, and electrochemical staining at the drip edge. Not dirt — chemical staining.
Because the staining is at the molecular level. Pressure has nothing to mechanically break loose. The fix is a chemical brightener.
No — brighteners are formulated for aluminum gutters and lift staining without harming the metal or paint coating.
Eventually — the underlying causes keep happening. But properly brightened gutters typically last 18-24 months before new staining shows.
Yes — the chemistry is safe for powder-coated and painted gutters. The brightening removes staining; underlying color is untouched.
Yes — we strongly recommend it. We're up at the gutter line for both services. Combined with house wash, it's one of our most-booked bundles.