Clean siding increases your house’s curb appeal–even if you are not planning to sell. Keeping siding clean extends its lifespan. Every type of siding should be well-cleaned yearly. Cleaning siding is not difficult, and if it is done regularly takes less than a day to complete.
General Cleaning Tips
Regardless of your type of siding, use these common cleaning practices to produce good results.
- Manufacturer’s Recommendations. Manufacturers usually provide specific cleaning instructions. Not adhering to them may void your warranty.
- Weather. Do not clean siding in direct sunlight or windy conditions. Heat dries the siding before it is clean and wind blows dirt onto wet siding.
- Plant Protection. Cover plants, gardens, and decks close to the house–especially when using bleach or chemicals.
- Cleaning Area. Clean small areas at a time to ensure complete cleaning. Ten-foot by ten-foot areas work well.
- Gravity. Rinsing from the top down minimizes streaks.
- Pressure Washers. Avoid pressure washers unless you know how to use one. Pressure washers can punch holes in stucco, dent aluminum, and scare wood. They can damage the siding and force water onto the framing behind it. Warranties may be void if you use one.
Cleaning Vinyl and Aluminum Siding
Vinyl siding is manufactured as a single color front to back. Aluminum siding has a paint finish. Both finishes oxidize in sunlight and have a chalky feel and look. They can be cleaned the same way.
- Mold and Mildew. Mold and mildew grow on the dirt stuck to the siding–not the siding itself. Scrub infected areas with a 50/50 bleach solution and a soft bristle brush. Wait at least 10 minutes before cleaning.
- Cleaning. Scrub the siding with a soft bristle brush and laundry detergent. You can add TSP to remove oxidation. Vinegar works just as well and is less expensive.
- Rinsing. Rinse the wall thoroughly with a garden hose.
Always scrub and spray aluminum and vinyl siding in the direction of the overlapping seams to prevent water from getting behind the siding. The bottoms of each piece of siding have weep holes to allow condensation to drain from behind the siding. Always rinse from the top down to avoid spraying water into the holes and behind the siding.
Cleaning Fiber Cement Siding
Fiber cement siding is a composite of cellulose fibers and cement with a paint finish. Harsh chemicals and scrubbing can damage it. Some cleaning tips include:
- Use a soft bristle brush and gentle detergent to remove accumulated dirt.
- Always brush in the direction of the wood grain. Scrubbing across the grain can leave scars.
- Spray the siding with a garden hose before scrubbing.
- Rinse thoroughly after washing. Fiber cement should be washed or sprayed every 12 months–or more if required.
Cleaning Wood Siding
Cleaning wood siding requires a very soft brush and very gentle detergent–whether painted, sealed, or left natural. Wood scars easily and paint flakes off if too much pressure is applied. Rinse thoroughly with a garden hose set at low pressure.
Pressure washing may be an option if you are planning to repaint. It helps to strip off old paint. Pressure washing siding–like pressure washing decks–is controversial because it can cause permanent damage if done improperly.
Cleaning Masonry Siding
Most people don’t think of stucco, stone, or brick as siding but they serve the same purpose–protecting the house from the elements. All of them have craggy rough finishes that collect dirt and dust.
Soak the area using a garden hose. Then scrub it down with a soft bristle brush and mild detergent to loosen caked-on grime. Use the garden hose to rinse it clean. All masonry siding should have a moisture barrier or rain screen behind it but avoid prolonged spraying around windows and cracks.
Safety
Take a few precautions when washing siding. Wear safety glasses to protect against dirt, loose stucco, and paint chips. If you are removing a lot of mold, wear a respirator and disposable gloves. Wear old clothes in case bleach or chemicals splash around.
Houses taller than two stories require getting on a ladder. If you are not comfortable washing your siding, consider hiring a professional.
