How to pressure wash a roof

How to pressure wash a roof
(Image credit: Getty Images)

Pressure washers aren’t just for patios. Learning how to pressure wash a roof can give the outside of your home a lift and prevent damage. If you’ve mastered pressure washing your patio, you may want to use this versatile tool to tackle your roof. New to pressure washing? Try starting with an easy surface like a patio to hone your technique or consult a skilled pro.

Don't forget to take precautions to protect yourself and your roof. We’ll guide you through everything you need to know about how to pressure wash a roof so you can tackle it with confidence. We’ll ask the experts for their top tips. 

You’ll want to ensure your pressure washer is suitable for the surface of your roof. Check out our guide to the best pressure washers that eliminate grime and allow you to fast-track your way to a cleaner home. 

How to pressure wash a roof

What the expert says…

Scott Reid, Exterior Home Expert at Angi explains that pressure washing your roof “can boost your curb appeal by removing any dirt and grime that has accumulated over the years."

So, why pressure wash your roof? Not only can pressure washing spruce up your roof, but it can also lengthen its lifespan. If left untreated, moss and algae can spread underneath your roof and cause damage.

First, you want to check if your roof material is suitable. Concrete, ceramic, and metal roofs can withstand high pressure and are excellent candidates for pressure washing. If, however, you have an asphalt shingle or a wooden roof, you’ll need to exercise caution as these materials are more delicate. You may need to use a low setting or wash these surfaces with a hose to avoid damage and costly roof repairs. Check your pressure washer manual before you start. 

Think safety first. A ladder is a no-no with all that slippery water. Instead, use a wand attachment for those hard-to-reach spots. Don’t forget to wear eye goggles and sturdy boots to protect against flying debris.

Allow the water to run for a minute to even out the pressure. Rinse the surface of your roof with low pressure (about 1200 PSI). For more brittle materials like asphalt shingle, opt for a fan nozzle, which is gentler than a concentrated jet. Next, apply a detergent to tackle tough grime. Finally, wash away the residue with your pressure washer and admire your handiwork.

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Louise Bond

Louise Bond is a UK-based writer and the founder of The Cove Copy. She has been published in The Guardian, Breathe, Fit & Well, Top Ten Reviews, and more. When she’s not writing, you can usually find her out in nature, whether hiking in the woods or pottering in the garden.