Is it safe to pressure wash your roof?

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Short answer: No, high pressure isn't safe for a roof. It strips the protective granules off shingles and can crack tile, which is why roofs are always soft washed at low pressure instead of blasted with a consumer-grade machine.

What high pressure does to shingles

The granules on a shingle roof protect it from UV exposure and hold the shingle together. High pressure removes them, and that loss is permanent, not something that grows back or gets fixed by a future cleaning down the road.

Once granule loss starts, the exposed shingle underneath ages faster under Florida's sun than a granule-covered shingle would, which is a bigger long-term problem than the staining the cleaning was meant to fix in the first place.

What it does to tile and other materials

Tile can crack or chip under high pressure aimed directly at it, and the same risk of surface damage applies broadly across roofing materials. None of them are built to take a direct high-pressure blast well, regardless of how sturdy they look from the ground.

Even a hairline crack in a tile can let water in during the next heavy rain, which is a bigger and more expensive problem than the algae staining the cleaning was supposed to fix.

Why soft washing is the safe alternative

A soft wash applies a cleaning solution at low pressure, which is enough to break down the algae and grime causing the staining without the force that damages the roofing material underneath it.

It's a slower process by design, since the solution needs time to break down the algae rather than relying on force to strip it off in one pass.

What about the fall risk

Beyond the material damage, roof work of any kind carries a real fall risk, which is a separate safety concern from the pressure question but still part of why this isn't a job to take lightly, whether it's done with a pressure washer or otherwise.

A wet roof surface, which is part of any cleaning process, adds another layer to that risk, which is one more reason this isn't a job most homeowners take on themselves.

Checking with your insurer or roofer

If you have questions about how any past pressure washing might have affected your specific roof's condition or manufacturer coverage, that's worth checking with your roofer or insurer directly rather than guessing at the answer yourself.

That's a reasonable step for any older roof, or any roof where you aren't sure what cleaning method was used in the past.

In Volusia County

Shingle roofs account for 77% of homes in Volusia County property records, the material most at risk from granule loss under high pressure. Roof cleaning across the county's homes prices at a typical $464 using the soft wash method on every material, from shingle to the county's 2% share of tile roofs.

Questions people ask

Can a soft wash still clean a heavily stained roof?

Yes, soft washing is effective on algae buildup regardless of how visible the staining is, since it targets the growth rather than relying on force to remove it.

Will pressure washing void anything with my roofing manufacturer?

That depends on your specific shingle or tile manufacturer's terms, which is worth checking directly with them or your roofer rather than assuming either way.

Is a soft wash slower than pressure washing would be?

It can take a bit more time, since it relies on the cleaning solution doing the work rather than raw force, but it's the method that protects the roof underneath.

Should I ask a roofer before booking a cleaning?

If you have any concerns about your roof's current condition, checking with a roofer first is a reasonable step, especially on an older roof.

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