Keeping your roof and concrete clean improves your home’s curb appeal, as well as protects it. This helps you avoid costly repairs and replacements due to damage and neglect.
Begin with loose dirt removal; sweep or vacuum surfaces. Spray or brush a concrete surface with a mild detergent to tackle mold and mildew stains (avoiding metal brushes that can scratch the surface). Rinse.
Dirt
The dirt that accumulates on a roof is not only unsightly but it can also lead to long-term damage. A professional cleaning service uses the right tools to effectively remove dirt and grime from your concrete or tile roof, and regular maintenance helps keep your home looking good between cleanings.
Roof tiles are completely exposed and therefore collect dirt relatively quickly compared to other areas of your home’s exterior such as windows, gutters, siding, or plants. This dirt can cause stains and lead to the growth of moss, mildew, or algae.
To avoid this buildup, it is important to trim overhanging branches that can leave debris on the roofscape. Regularly rinsing your roof with a garden hose or pressure washer also keeps it clean and clear.
If your concrete roof is a common place for moss or mildew to grow, using a non-toxic biodegradable cleaner formulated specifically for roofs can break down the growth and prevent further buildup. Using a low-pressure wash with a soft-bristled brush is also effective for removing dirt, grime and stains.
For a truly deep clean and effective stain removal, you can use a mold or mildew killer spray that is safe for use on concrete. Apply it as per the instructions on the label, then rinse with a garden hose or power washer at a lower pressure setting to avoid damaging your concrete roof.
Algae
Algae are primitive plants that grow in water and wet surfaces like roofs. They are black or green and form a thick, gooey film that can cause problems by staining surfaces and blocking sunlight. Although algae isn’t harmful, it can be difficult to remove and creates dark streaks on your roof that make it less attractive. Algae also provide a foothold for other organisms like moss and lichens that can damage your shingles and clog gutters.
The spores of these “algae” spread on the wind, so it isn’t uncommon for them to land on your neighbors’ homes, carports, or sheds, as well. If left unchecked, this can lead to mold and mildew, which can impact your family’s health.
The best way to prevent algae is by making the environment hostile for spores to thrive in. This includes trimming overhanging branches, improving drainage, and securing your gutter system to keep it free from debris. Also, using zinc or copper strips on the roof to deter fungi from growing is helpful. These sacrificial metals release small particles of zinc or copper with each rain that kill the spores and keep your roof algae-free. A licensed roofing contractor can recommend these products and help you install them. They can also perform a roof treatment to prevent future algae growth and ensure that any damage to your shingles is repaired.
Debris
Debris from trees, fallen leaves, twigs, and debris can cause roof damage, block gutter drains, and even lead to leaks. Debris removal is a key part of regular roof maintenance and cleaning, especially in areas with frequent storms. The best tools for this job are a sturdy ladder, a roof rake, and a garden hose. You’ll also want to trim back overhanging branches to help prevent more debris from gathering and make sure the gutters are clear of any clogs.
For concrete roofs, a pressure washer with the appropriate pressure setting is useful for washing away larger particles like broken or loose shingles. Using too much pressure can damage the surface, so it’s important to use a low or moderate setting. You may also choose to use a concrete cleaning solution that removes dirt, mold, and mildew.
One of the most difficult issues to deal with on concrete roofs is moss. This plant grows in tiny indentations on the surface of concrete, which power washing, scraping, and brushing can’t get rid of. A thorough and ongoing sterilization is the only way to keep moss and other growths from settling in. This is possible with ROTban, which permanently bonds to concrete and creates a permanent fungicidal environment that stops spores from taking root. This is a cost-effective and long-term approach to protecting your investment in a concrete roof.
Stains
Concrete stains from oil spills, grill grease, pet urine, bird droppings, and other causes can leave your driveway, sidewalk, or patio looking dingy. While you can usually remove these stains by blotting them with paper towels and scrubbing them with a brush, a degreaser will help get rid of any remaining residue. Always follow the degreaser’s instructions for best results and do not use bleach as it will strip the grey color from the concrete leaving you with a discolored area.
Stains on the roof can be caused by algae, moss or from dirt and debris that has made its way to the surface. If you can’t remove the stain with a pressure washer or scrubbing, you can try mixing one part bleach with three parts water and applying it to the roof tiles. Be sure to wear protective gloves, a respirator mask and goggles to protect your eyes and lungs from bleach and other chemicals.
The easiest way to keep your roof clean is by trimming overhanging trees and keeping the gutters clear of leaves, twigs, and other debris that could fall on the roof. Regularly hosing off the debris, especially after it rains, also helps minimize stains. Cleaning your concrete walkways, driveways and garage floor with a degreaser regularly helps keep them looking fresh and new.