How to Powerwash Your Siding

A woman powerwashing her house.
  • 2-10 hours
  • Beginner
  • 200-1,500
What You'll Need
Cleaning agent (optional)
Plastic tarps
Eye protection
Protective shoes
What You'll Need
Cleaning agent (optional)
Plastic tarps
Eye protection
Protective shoes

Have you noticed that the outside of your house is looking a little dingy? It's possible that your siding may need a bath. Powerwashing is a great way to renew the exterior of your home.

A powerwasher, also known as a pressure washer, is a high-pressure sprayer that is used to remove mold and dirt from house siding as well as other surfaces.

If you weren't able to power wash your siding in the spring or summer, you still have time. Fall is the perfect season to clean up.

Step 1 – Rent or Buy a Powerwasher

A person powerwashing a deck.

You'll need to decide whether you want to rent or purchase a powerwasher. You can usually rent a powerwasher by the day from any home improvement store. However, it's also nice to have a powerwasher on hand for other tasks, so you may want to consider purchasing one. Should you choose to buy a pressurewasher, you'll find there are many other uses for it. Consider using your powerwasher to clean the following items: garden equipment, patio pavers, patio furniture, patio umbrella, fabric hammocks, driveways, vehicles, door and car mats, and decks.

Pros and Cons of Renting a Powerwasher


It's cheaper than buying.

You don't have to store it.

You don't have to worry about maintaining it.


It's more expensive long-term (over several rentals).

You have to use it within the allotted rental time, or you risk extra fees.

Pros and Cons of Buying a Powerwasher


You'll always have it on hand to use every year.

You can use it for other household cleaning projects.

You don't have to worry about completing your task within the rental period.


It's more expensive.

You'll need to store it.

You'll need to maintain it to keep it working long-term.

Step 2 – Purchase a Cleaning Agent

You can use a powerwasher with straight water. However, a cleaning agent will help remove dirt and any mildew that has accumulated on your siding.

There are several different types of cleaning agents available. Make sure to ask the rental or sales associate if there is a specific cleaner that goes with the pressurewasher you choose. Otherwise, choose a cleaning agent made for powerwashers and for the type of siding material and conditions you have. If your siding has mildew, you'll want a cleaning agent that specifically treats mildew. If you are concerned about the environment, there are also green cleaning options available.

Step 3 – Cover Your Landscaping

Depending upon the cleaning agent you are using, you may want to cover the landscaping around your home with plastic tarps. This will help to keep any cleaning chemicals off of your plants. You can also water all of your plants before covering. This will help to dilute any cleaning chemicals that do happen to fall onto your plants or soil.

If there are any shrubs touching the side of your house, you may want to trim them back first.

Step 4 – Pre-cleaning Tips

A man washing his siding with a brush.

If your siding is extremely dirty, you may need to use a brush to clean tough spots before power washing.

You'll want to set up your powerwasher and cleaning agent using the manufacturer instructions.

You'll also want to read up on the different pressure and spray settings available. Low pressure won't clean as well, however, high pressure could take the paint off of wooden siding.

When pressurewashing, it's best to use eye protection to keep any detergent and debris out of your eyes. Ear protection may also be necessary for gas-powered powerwashers. Always wear protective shoes when using a pressure washer. (Don't go barefoot or wear sandals.)

If you are using an electric powerwasher, make sure that the outlet you are using is dry and off the ground. Never touch the outlet or plug if your hands are wet.

You should always stand on a stable surface where you are on solid ground and have good balance. If a ladder is necessary to reach higher portions of your siding, make sure that you have a partner to help hold the ladder. You can also purchase or rent extension handles for hard-to-reach spots.

Consider powerwashing a test spot first to ensure that that washer does not damage your siding.

You'll also want to think about whether your gutters need cleaning as you'll want to powerwash them first.

You can also powerwash your windows, though you may want to use a different cleaning agent.

Step 5 – Start Cleaning

Working in small sections, apply the detergent from the bottom up. This helps to prevent potential streaking. Allow the detergent to remain on the siding for a few minutes, but do not let it dry.

When you are ready, rinse the detergent off the siding with water only. Start top to bottom, so that the dirt runs down the siding. Work in small sections.

Continue with this method until you have cleaned your entire house.