Tips on Cleaning Your Siding

Exterior siding on your home has many benefits. It can insulate and protect your home and is great for displaying a positive curb appeal. However, if your siding is dirty, it creates a negative impression to passers-by or visitors. Keeping your siding clean should be part of your overall home maintenance plan.

Causes of Dirty Siding

Dirt, grease or mildew are the biggest elements that you’ll need to clean from your siding. They can originate from various sources and the amount accumulated will depend on your location and activities occurring on or near your property. Some examples of causes that contribute to dirty siding:

  • dirt and yard debris blowing or splashing onto the siding
  • pollen floating in the wind and sticking to your siding
  • bird or critter droppings
  • spider webs
  • mildew
  • chemicals that may result from work done near or around your house

Basic Siding Cleaning Tips

Although the process and materials used for cleaning siding may vary depending on the type of siding you have, there are some common tips to follow and what to avoid.

1. Clean Your Siding at Least Annually. 

Depending on your location, it may be sufficient to clean your siding once a year. If you live where construction is ongoing, or there are lots of open fields, your siding may get dirty more quickly. If you notice an accumulation of dust, dirt or grease, it’s a good idea to clean it as soon as you can.

2. Refer to Manufacturer’s Instructions.

When your siding was installed, you probably received instructions on caring for and maintaining your siding. Warranties on some siding products may be dependent on maintaining it properly and using the recommended cleaning products and processes. If that’s the case, it’s important to follow their guidelines to avoid the warranty being invalidated.

3. Wear Appropriate Attire.

Don’t make the mistake of assuming washing siding is the same as washing a car. To avoid injury while cleaning your siding, you should wear clothing that is comfortable and washable. Wear closed-in shoes, rubber gloves and safety goggles to protect your eyes from falling debris. If you’re sensitive to the chemicals being used, a face mask can help with breathing.

4. Clear the Area.

Remove objects that are around the home’s exterior so they don’t get in your way during cleaning. These include outdoor furniture, toys and other items that may inhibit your access and possibly cause accidents.

5. Protect Indoors and Stationary Items.

Make sure all windows and doors are closed tightly during the cleaning process to avoid spraying inside the house. Plants and other landscaping items should be covered to prevent them from damage by any cleaning products. Any lights and electrical plugs should be turned off, unplugged and/or covered to avoid electrical shock. For extra protection, securing the covers with duct tape can further protect them from the water.

6. Clean in Sections.

Although not necessarily a mandatory requirement, it can make the job more manageable if you clean your siding in small sections. It’s also better to work your way from the top to the bottom of the siding.

These basics apply to cleaning all types of siding. There are more specific requirements for the different types of siding materials. Below are some tips for cleaning fiber cement, vinyl, aluminum and wood siding.

Cleaning Fiber Cement Siding

Fiber cement siding, especially James Hardie fiber cement siding, is probably the easiest type of siding to maintain. Since James Hardie fiber cement siding is resistant to mold, mildew and fading, it typically doesn’t need cleaning as often as other siding materials. However, it will need some occasional care.

The tools you’ll need for removing most soil elements are pretty simple:

  • Soft cloth or sponge - or -

  • Soft paint brush, chip brush, horsehair brush or siding brush

  • Water hose

The process and cleaning products recommended depend on the type of soil or contaminants that are on the siding. There are basically three categories.

Construction Debris, Dust or Chalk

Start by removing the loose dirt and debris from the siding with a soft brush or soft damp cloth. After brushing away all loose dirt and dust, simply rinse the siding with plain water using your garden hose.

Oil, Grease or Non-chemical Debris

Mix a little mild dishwashing detergent (Dawn®, Ivory® or Joy®) with water in a bucket. (Never use harsh chemicals to clean fiber cement siding.) Use a soft brush or cloth and apply the solution to the siding. Use your garden hose to rinse off the solution. Re-apply to any missed areas.

Mold and Mildew

If you live in an area where moist, humid weather occurs, your home’s exterior siding is susceptible to mold and mildew. These can also be removed effectively, but with a different cleaning agent. Cleaners that are safe for fiber cement siding include Jomax®, Mildew Check® or Mold Armor®, and can be found at your local hardware or home improvement store.

Some of these products may be in concentrated form, requiring a much smaller amount to clean effectively. It’s important to follow the instructions for the cleaning solutions, using the recommended amounts and process noted on the product label to avoid damaging your fiber cement siding. Don’t forget to protect yourself and landscaping when using these strong cleaning agents.

Mix the cleaning products with water in a bucket and use a soft cloth or brush to gently scrub away the mold and mildew. Once they are completely removed, rinse the siding with your garden hose. Don’t allow the solution to dry, as it will leave a film. Make sure to keep it wet and remove it completely.

Is Power-Washing Okay?

If you have a large area to clean, power washing can expedite the process. However, use extreme caution if you decide to do so. The pressure of a power washer can damage fiber cement siding. If you are unsure, you may want to hire a professional experienced with cleaning fiber cement siding.

If you decide to power wash, make sure you take the following precautions to minimize any damage to the siding.

  • Use wide fan tips.

  • Keep a minimum distance of 6 feet from the wall.

  • Use pressures under 1500 psi.

Cleaning Vinyl Siding

Cleaning vinyl siding is relatively simple. Just as with fiber cement siding, a soft brush or cloth is recommended to wipe away most dirt and debris. If the siding is textured, a brush is a better option, since it reaches between the grooves to remove imbedded dirt and prevent staining.

Cleaning Products for Vinyl Siding

Several common household cleaners can be used to clean vinyl siding. These include:

  • Vinegar - When mixed with water, it effectively removes dirt and grime and even light mold and mildew. The recommended solution is 70% water, 30% vinegar.

  • Bleach - Mixing one quart of bleach with a gallon of water helps to disinfect the surfaces. It also will make siding that has been discolored white again. The disadvantage of using bleach is that it is harsh on skin and the environment and gives off toxic fumes. If you wear protective gear like gloves and mask, and protect foliage, it should be fine.

  • Common store-bought cleaning products like Fantastik, Murphy’s Oil Soap, Windex and Lysol can also be used for tougher stains like bubble gum, grease, crayon and ink.

  • Tougher dirt may require a stronger solution, using ⅓ cup powdered laundry detergent and ⅔ cup trisodium phosphate cleaner with a gallon of water.

Power Washing

You can use a power washer to clean your vinyl siding, but use caution to avoid damaging the siding. Aim the washer spray at eye level, pointed downward toward the top of the siding panels. If you direct the spray upward, it can drive water behind the siding, causing mold and mildew and possibly loosening the siding. Above all, check the manufacturer’s recommendations for limitations on the use of power washing to avoid nullifying your warranty.

Cleaning Aluminum Siding

The process and materials used for cleaning aluminum siding is very similar to that for vinyl siding. You can start with a simple overall rinse of the siding with your garden hose. You can then use a soft brush or cloth and cleaning products to hand-clean the surface. Always rinse cleaning agents from the siding before they dry.

As with any type of siding, take care when using a power washer to clean aluminum siding. If you decide to power wash, you may want to buy or rent one that accommodates mixing water and cleaning materials together. That way you can spray the siding with the cleaning agents, then rinse with plain water.

Cleaning Wood Siding

The most common types of wood siding are made from cypress and cedar. Wood siding can be cleaned but if you don’t do it right, you may be causing more harm than good.

As with any other siding, a pressure washer should be used with caution. Do so only after you check manufacturer’s guidelines and are confident in your ability to use it properly without damaging the siding. Improper usage could strip paint, gouge boards, loosen caulking and trap moisture in your siding. Standing moisture will result in mold growth and wood rot.

Tools and materials for hand-washing wood siding are similar to those used to clean other types of siding. Soft cloths and brushes, your garden hose and bucket are things to have on hand. A ladder is also necessary for reaching high spots.

Cleaning products that can be safely used on your wood siding include oxygen bleach and organic stain solvents. TSP, or Trisodium Phosphate Powder, is also a good recommendation for clean wood siding. You can find this product in many home improvement stores. Mix half a pound of TSP with two gallons of water in a bucket.

Make sure to check the labels to make sure it’s safe to use on wood. Avoid using cleaners that contain chlorine bleach that could strip the color from your siding. Also stay away from cleaning the natural oil stains in the wood.

In summary, all types of siding can be kept looking clean and fresh with regular maintenance. However, James Hardie fiber cement siding requires less maintenance than others and lasts for decades.

Banner Construction Specializes in James Hardie Fiber Cement Siding

Banner Construction has a proven record as a James Hardie Elite Preferred Contractor. That means we are certified in the quality installation and service for the James Hardie Plank Siding, related trim, and other accessories. All of our sales consultants and installation crews receive the required James Hardie factory training.

Call us today to see how we can make your home the envy of the neighborhood with long-lasting, beautiful James Hardie fiber cement siding.