Look for products that have been approved specifically for use in pressure washers. [3] X Expert Source Ben BarlowWindow Cleaning Specialist Expert Interview. 23 July 2021. Cleaning with water alone won’t kill mold and bacteria, which means it’s possible for them to make a quick comeback. [4] X Research source

A standard gasoline or electric washer with a pressure rating around 3,000 PSI should provide more than enough force to effectively clean even hard-to-reach places. Perform a few test sprays on one of the lower corners of the siding to help you get used to the power. Double-check that the water is turned on before you start using your pressure washer. [6] X Expert Source Ben BarlowWindow Cleaning Specialist Expert Interview. 23 July 2021.

Even the most persistent stains shouldn’t require you to use more than 3,000 PSI. [7] X Research source

If needed, you can go over the same spot a few times to loosen stubborn dried buildup. Take your time. Long-standing messes may not come off right away.

Avoid spraying in circles, swirls, or other indiscriminate patterns. Not only is this inefficient, it can also leave behind noticeable streaks due to the way it pushes the dirt around.

Look closely for any small patches dirt or grime that you may have overlooked before moving on to rinsing.

You may have to stand on a ladder to hit the upper areas of the exterior without pointing the nozzle upwards. If too much water become trapped, it can cause bulging, mold buildup, and electrical issues, or even weaken your home’s framework or foundation.

Do not allow the solution to dry completely. It could leave behind unsightly streaks or scummy residue. [13] X Research source Rewet the sections you’ve gone over previously as needed to prevent them from drying while you work on the rest of the siding.

Since you’ll potentially be encountering mold, mildew, algae and other icky substances, it’s important to make sure there’s a barrier in place over your nose and mouth. A pair of goggles or other form of eye protection can also come in handy for preventing water from splashing back into your eyes.

Assuming off-site storage isn’t an option, move furniture and appliances a safe distance away from where you’ll be operating the pressure washer.

Go ahead and unplug anything that’s currently connected as an added safety precaution. If you’re unable to find covers to fit your home’s outlets, you can conceal them with small squares of plastic anchored with waterproof tape.

Bleach is mildly caustic and can irritate your skin if it gets on you, so be sure to wear gloves. [18] X Research source A preliminary bleach treatment will help eliminate the worst of the mold, making it easy for the pressure washer to take care of the rest.

Alternatively, you can also use a garden hose for a gentler touch. Fitting the nozzle with a 40 or 60 degree spray tip will allow you to cover a much broader surface area at once.

If necessary, take an occasional break to give the excess runoff time to drain.

Plan your project for a day with warm, dry conditions to help speed up the drying time.

If you live in a cool, moist climate or your home is situated in a shady location where it doesn’t receive much direct sunlight, you may need to increase the frequency to once a year. Following an initial pressure washing, you’ll most likely be able to get by with some old fashioned elbow grease until time and inclement weather make another deep cleaning necessary.

For a little extra scrubbing power, opt for a Brillo pad or use a stiff-bristled scouring brush. One of these tools will be able to dig into the soft surface of the vinyl better than an ordinary cloth or sponge. [23] X Research source Add touching up your exterior to your list of bi-monthly chores to complete around the house.

Over time, exposure to the elements or the impact from falling tree branches and other debris can cause considerable wear and tear. If not addressed right away, damaged siding can become an eyesore or even fail, putting your home at risk for more serious issues like leaks, drafts, and water damage. [25] X Research source