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 on passers-by or visitors.

Siding is versatile, durable, and resilient, but like other aspects of home improvement and maintenance, it requires routine cleaning and care. Keeping your siding clean should be part of your overall home maintenance plan.

Why You Need to Clean Siding

Because siding is an outdoor product, it can accumulate dirt and stains due to several factors. Learning a few siding cleaning and maintenance tips is helpful to keep your home’s exterior aesthetically appealing.  Keeping the siding clean also extends its life.

After multiple seasons of abuse from the weather, your siding may take on a different hue or look a bit dull or dingy. This is normal but can ruin the aesthetics of your home, as well as wear away at the siding material over time.

Some good reasons to keep your siding clean and maintained include:

  • It’s unsightly. Homeowners naturally want a beautiful home that looks great from the curb. Dirt and mildew create stains that look unattractive.
  • It’s unhealthy. Mold and mildew can produce health issues.  They can cause allergic reactions and skin irritations.
  • It’s a warning sign. The appearance of mold and mildew can mean that your home is trapping moisture underneath the siding. This is an issue common in older homes where the siding was not properly installed.

Causes of Dirty Siding

The siding on your home can get dirty from many sources. 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 are as follows.

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

Reasons for Mold Growth on Siding

There are three main issues that can result in mold and mildew forming on siding.

1. Dirt Buildup

One of the main reasons that mildew or mold form on siding is that dirt has accumulated on the surface. Not only does that make the siding look unclean, but it can also lead to mildew. This fungus often feeds on dirt and dust. In addition, if the home is near trees, some sugary sap from those trees could end up on the siding, and that’s also appealing food for the fungus.

2. Excess Moisture

When water remains on a  surface that is covered in small particles of dirt like siding typically is, fungi spores can grow. These spores produce visible mold and mildew. It could be that rainwater got trapped behind the siding or even within the material itself. It’s also possible that there’s a broken drainpipe or gutter constantly dripping water on the siding, causing it to stay wet. That’s an invitation for mold or mildew to start growing on a house.

3. Lack of Sunlight

If part of the house is constantly shaded and receives very little sunlight, it’s more likely to develop a fungus problem. That means that moisture doesn’t have a chance to evaporate.  In some cases, there’s a tree, shed, or porch roof that keeps one side of the house from receiving sunlight. Getting rid of this source of shade can help prevent mildew or mold from growing

If moisture, lack of sunlight and dirt are all common causes of fungus growth on siding, preventing this problem should involve getting rid of these potential causes. Another way to prevent mildew on siding is to stay on top of siding maintenance. That includes cleaning it regularly to keep mildew and mold at bay.

Basic Siding Cleaning and Maintenance Tips

Homeowners who love the look of their house siding understand that regular maintenance is key to keeping it looking great and extending its lifespan. The accumulation of unsightly dirt, pollen, pollution, and more can go a long way toward diminishing your home siding's overall appeal.

You may be pleasantly surprised by the rejuvenating effect of a good siding cleaning, with a cleaning product and technique that won't damage the material of your siding. Although the process and materials used for cleaning house siding may vary depending on the type of siding you have, there are some common tips to follow and what to avoid. .

To keep your fiber cement, wood, vinyl, or aluminum siding clean, you should follow the basic maintenance steps outlined below.

1. Clean Your Siding Annually (at least).

Depending on your location, it may be sufficient to clean your house 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 that 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. Items like outdoor furniture, toys, and other items that may inhibit your access and possibly cause accidents.

5. Protect Indoors and Stationery 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.

6. Clean in Sections.

Cleaning house siding in small sections can make the job more manageable. It’s also better to work your way from the top to the bottom of the siding.

Cleaning Different Types of Siding

Although there is basic cleaning and maintenance that applies to all types of siding, some materials require extra care. Below are more specific requirements for the different types of siding materials: fiber cement, vinyl, aluminum, and wood.

Fiber Cement Siding Cleaning

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 from fiber cement siding are pretty simple:

  • Soft cloth or sponge
  • Soft paintbrush, 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 three categories.

1. Removing Construction Debris, Dust, or Chalk

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

2. 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 cleaning solution to the siding. Use your garden hose to rinse off the solution. Re-apply to any missed areas.

3. 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.

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.

Vinyl Siding Cleaning and Maintenance

Cleaning vinyl siding is relatively simple. 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 embedded dirt and prevent staining.

Several common household cleaners can be used to carry out vinyl siding cleaning and maintenance.  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 the skin and the environment and gives off toxic fumes. Protective gear like gloves and masks should be worn along with protecting the foliage.
  • 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 cup trisodium phosphate cleaner with a gallon of water.
Cleaning Aluminum Siding

The process and materials used for cleaning aluminum siding are 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. That way you can spray the siding with the cleaning agents, then rinse with plain water.

Keeping Wood Siding Clean

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 cleaning any type of house siding, a pressure washer should always be used with caution. Do so only after you check the manufacturer’s guidelines and are confident in your ability to use the tool properly without damaging the siding. Improper usage could strip paint, gouge boards, loosen caulking, and trap moisture in your siding.

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 a 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. or Trisodium Phosphate Powder (TSP) are good recommendations for cleaning wood siding.

You can find these products in many home improvement stores. 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.

Banner Construction Specializes in James Hardie Fiber Cement Siding

In summary, all types of siding can be kept looking clean and fresh with regular maintenance. However, if you’re looking for siding that looks great, requires less maintenance than other siding types, and lasts for decades, choose 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 James Hardie factory training to maintain our certification.

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.