Can You Pressure Wash Roof Shingles? The power washer could have wiped thousands off the value of your house. Here’s the reason. Dirt and algae make roofs appear dirty. However, pressure washing could cause irreparable damage. In reality, 72% of warranty claims are rejected because of improper cleaning. This guide explains the possibility of pressure washing roofing shingles, as well as the damage it can cause, and safe alternatives to maintain your roof’s pristine condition.
The Short Answer
- Asphalt Shingles: Do not pressure wash, as it rips off the protective granules.
- Ceramic Tiles: The tile is a possibility, but be cautious (under 1500 PSI).
- Wood Shakes: Do not use them as they can cause splitting and decay.
Understanding the type of roof you have is crucial for safe and secure cleaning. Learn about our Roofing Installation Services here!
Why Pressure Washing Damages Shingles
1. The Granule Problem
Asphalt shingles are based on mineral granules to provide UV protection. Pressure washing can remove 5 to 10 percent of granules with each run. This reduces the lifespan of shingles by as much as 30%. This exposes asphalt to harmful UV rays, which can accelerate cracking.
2. Water Intrusion Risks
High-pressure water force under the roofing shingles, which causes:
- Leaks and decking that has rot.
- The growth of mold within the attic space.
- Warranty cancellations – most manufacturers ban the use of pressure washers.
These dangers are what make the pressure washing process void of roof warranties, the most important concern. Check out our Roof Replacement and Roof Repair Services here!
Safe Alternatives for Cleaning
Method 1: Soft Wash System
- Utilizes very low pressure (100 PSI) with biodegradable cleaning agents.
- Cost: $0.15-$0.30/sq ft, professionally. DIY is $50-$100 using an outdoor sprayer and a 50:50 bleach/water mix.
Method 2: Hand Cleaning
- Soft brush extension pole and a rinse bucket.
- The best for small areas that are heavily stained.
Method 3: Preventative Treatments
- Copper/Zinc Strips: Place them on the roof’s highest point to eliminate algae naturally.
- Shingles are 10-15 per cent more expensive, but they are worth it to replace them.
They are the most effective methods of cleaning roofing shingles. For commercial buildings, check out our Commercial Roofing services!
Final Thoughts
Can You Pressure Wash Roof Shingles? Your roof was designed for water drainage, but not to withstand blasts from firehoses. The pressure washing of asphalt roofing removes the granules, invalidates warranties, and can cause leaks. Choose alternative methods of cleaning your roof instead of pressure cleaning, such as hand or soft cleaning, to protect your investment. If you find granules in your gutters following cleaning, you’ve already caused damage to occur. Contact OnlyRoofing to avoid expensive repairs.
