Asphalt shingles are one of the most popular roofing materials for homeowners in Houston, TX, thanks to their affordability, versatility, and reliable weather resistance. However, even the most durable roof needs proper care to look its best and perform at its peak. One often overlooked aspect of roof maintenance is cleaning—especially in a humid, storm-prone climate where algae, moss, and debris build-up can take a toll over time.
In this step-by-step guide, we’ll walk you through how to safely and effectively clean asphalt shingles, extend your roof’s lifespan, and preserve your home’s curb appeal.
Why Clean Your Asphalt Shingle Roof?
While it might seem cosmetic at first glance, keeping your shingles clean can actually prevent long-term damage. Here’s why:
- Moss and algae retain moisture that can cause shingles to deteriorate or lift.
- Debris and buildup can clog gutters, leading to water backup and leaks.
- Discoloration from growth and grime can reduce the roof’s energy efficiency and aesthetics.
- Routine cleaning reveals minor issues before they turn into expensive repairs.
In a climate like Houston’s—with high humidity, frequent rain, and abundant tree coverage—these issues can develop faster than you think.
What You’ll Need
Before you begin cleaning, gather the following tools and materials:
- Soft-bristle brush or broom
- Garden hose with spray nozzle (no pressure washers!)
- Oxygen-based bleach or commercial roof cleaner (non-corrosive)
- Safety harness and non-slip footwear
- Ladder and stabilizer
- Protective eyewear and gloves
Avoid harsh chemicals like chlorine bleach, which damage your shingles, harm landscaping, and corrode flashing.
Step 1: Safety First
Working on your roof involves risk. Never attempt to clean your roof alone—always have someone nearby. Use a safety harness, stable ladder with a stabilizer, and soft-soled shoes to reduce slipping.
If your roof has a steep pitch, is difficult to access, or shows signs of structural weakness, it’s best to hire a professional.
Step 2: Remove Loose Debris
Begin by sweeping off branches, leaves, and loose dirt with a soft brush or broom. Avoid using anything abrasive that could scrape off the protective granules on your shingles.
Work from the top down to avoid pushing debris under the shingles or into the gutters.
Step 3: Apply Cleaning Solution
Mix your oxygen-based bleach cleaner with water as directed and apply it using a garden sprayer. Saturate the affected areas evenly and allow the solution to sit for 15–20 minutes. This will loosen stains, algae, and moss without causing harm to your shingles.
Do not allow the solution to dry completely, as this can leave residue or cause streaks.
Step 4: Rinse Gently
Using a garden hose on a low-pressure setting, gently rinse the shingles from the top down. Avoid using a pressure washer—it can strip away the protective granules and significantly shorten the lifespan of your roof.
Make sure all cleaner residue is washed away, and take care not to force water under the shingles.
Step 5: Inspect for Damage
Once clean, take the opportunity to inspect your shingles for cracks, lifting, granule loss, or mold. Check flashing, vents, and ridge caps while you’re up there. Spotting early damage can help you schedule quick repairs before problems escalate.
If you’re unsure about what to look for, or if you discover something concerning, it’s time to contact a professional roofer for a full inspection.
How Often Should You Clean Your Roof?
Most roofs in Houston should be cleaned every 1–3 years depending on nearby trees, humidity levels, and whether your home is prone to algae or moss growth. If you notice black streaks or green patches forming, it’s a good time to schedule a cleaning.
Preventative measures like trimming back overhanging branches and installing zinc or copper strips along the ridge can also help reduce organic growth.
Trust the Professionals
While DIY roof cleaning is possible, improper technique can damage your shingles and void your warranty. For homeowners who want peace of mind and a job done right, professional roof cleaning is a smart choice.
TrueWorks Roofing offers thorough roof maintenance services designed to keep your asphalt shingles in peak condition. From safe, eco-friendly cleaning methods to detailed inspections, TrueWorks Roofing helps Houston homeowners protect their investment and extend the life of their roof.
They also specialize in installing high-quality shingles like those from Malarkey Roofing Products, which feature advanced algae resistance and UV protection, making them even easier to maintain over time.
Final Thoughts
Keeping your asphalt shingle roof clean isn’t just about appearances—it’s about preserving the function and performance of one of your home’s most important components. With the right tools, techniques, and professional support, you can ensure your roof stays clean, strong, and beautiful for years to come. Read also our blog: Is a Tile Roof the Right Fit for Your Residential Home?