Dirt, grime, and debris are common problems on asphalt roofs. Couple them with algae and moss patches and your home’s curb appeal is in ruins. Cleaning your roof shingles is a great way to stave off damage from buildup on your roof.
Algae and moss often develop on the northern and western facing and shaded parts of the roof. Algae forms dark, hideous, and unsightly black streaks. It’s generally not harmful, but it isn’t pleasant to look at, either. Moss forms large thick, green patches that trap dirt and debris on your roof and can cause your asphalt shingles to curl and blow off in the wind.
Cleaning roof shingles can be a risky undertaking, and not everybody is comfortable handling it themselves. Ideally, it’s best to have a professional clean your asphalt shingle roof. But if you’re up for it, you can do it yourself following our simple tips.
Here’s how to clean the shingles on your roof like a professional and avoid any unnecessary damage in the process.
What you’ll need to clean your shingles:
- Sodium hypochlorite (bleach) solution
- Garden sprayer
- Protective clothing
- Clean water
- Garden hose
- Shoes with non-slip rubber sole
Inspect the roof for damage or leaks
Safely climb up your roof using the ladder and check for loose or cracked shingles and flashing. If any part of your roof is damaged, contact a professional roofing contractor right away to avoid negatively impacting your roof while trying to clean it. Next, establish what kinds of growth you’re dealing with. Common issues are fire moss, hearty algae, lichen, black streaks, or Gloeocapsa magma.
Clean the gutters
Clear out the clutter and leaves from your gutters with a leaf blower to ensure clear passage of water when washing the roof. Blocked gutters could lead to backup that could damage the roof that you’re trying to clean. Regularly clearing out your gutters is a great idea anyway, so this is the perfect opportunity to carry out two tasks at once!
Clear the debris off your roof
Sweep away any debris from the roof before wetting, as leaves and twigs tend to stick to the shingles when wet. Blow away the twigs and leaves with a leaf blower and sweep off any remnants with a soft brush.
Mix bleach and water in your garden sprayer
Professional roofers use 12.5% Sodium hypochlorite, otherwise known as bleach, to clean roof shingles. You can buy sodium hypochlorite at the hardware store, but you can also use generic laundry-strength bleach to do the job. Dilute the bleach with water and put it in the garden sprayer.
The mixing ratios depend on the nuisance you need to clean off your shingle roof.
- Fire moss, hearty algae, and lichen: 75% and 25% water
- Gloeocapsa magma, black streak, or light black algae: 50% bleach and 50% water
- Light Gloeocapsa Magma stains: 25% bleach and 75% water
Protect your vegetation
Before starting the cleaning process, pre-soak the nearby plants with clean water to protect them from overspray. For extra protection, rinse off the plants once more once you’re done cleaning the roof. You can also cover your plants with plastic sheeting to keep them from coming into contact with any errant bleach.
Clean your roof shingles
It’s time to start cleaning! Be sure to avoid stepping on wet surfaces that may be slippery, and protect your skin and eyes while handling bleach. Apply an even coat of bleach solution on the entire roof, taking more time on the dark stained areas.
Typically, algae should disappear or turn white within five minutes of applying the asphalt roof cleaning solution. Re-apply the solution to any problem areas that you encounter. Use a more concentrated bleach solution on areas with a dense moss patch.
Rinse the roof with clean water
Leave the bleach solution on the roof for about 15 minutes, then thoroughly rinse off the chemical with clean water. Make sure to get every inch of the roof to clean off every trace of the bleach.
If you have plants near the house, now is the time to spray them again with clean water to rinse off any bleach solution that may have contaminated them.
Precautions when cleaning a shingle roof
- Always check your roof for weak spots and damage.
- Repair any noticeable roof damage or have a professional fix the loose flashings, shingles, and clean the downspouts and gutters.
- Clean your shingle roof on an overcast day with little to no wind.
- Avoid cleaning your roof on a sunny day. Excess sun may cause the mixture to evaporate before soaking through the growth.
- Hire a professional if you’re afraid of heights or your home is more than a story high.
If you find any damage on your roof or would like to turn your cleaning surfaces over to professionals, contact Midwest Roof & Solar today to schedule a free inspection. We look forward to working with you!