Concrete Roof Cleaning Guide
Concrete tile roofs are durable and long-lasting, but they aren’t maintenance-free. Over time, moss, algae, and pine needles can build up, leading to damage if not properly cleaned. In this guide, we’ll break down the safest and most effective methods for cleaning your roof—without causing unnecessary damage.
Aren’t concrete roofs lifetime roofs?
Are Pine Needles and Organic Growth really a problem?
In areas surrounded by Evergreen trees, like much of Washington State, pine needles tend to accumulate between the cracks of concrete tiles. Over time, this buildup creates a damp environment where moss, algae, and lichen thrive. If left untreated, this organic growth can lead to premature tile deterioration and even structural damage.
The key to long-term roof health is removing debris and treating the surface to prevent regrowth. Similarly, Moss and a Bacteria (the black staining you may see) not only cause your roof to retain more water, but can also be detrimental to the long term life of your roof.
How should my roof be cleaned properly?
Concrete tile roofs are durable, but they require special care when it comes to cleaning. Traditional pressure washing can lead to water intrusion under the tiles and erosion of the protective surface coating, making them more porous and vulnerable to moisture damage.
There is actually a lot of debate in the exterior cleaning industry about the proper way to clean a concrete roof. Some contractors will tell you that it’s ok to pressure wash them, others will say that you should only ever soft wash them (low pressure, chemical cleaning).
But what’s really the right way to clean my concrete roof? And how can I know for sure?
The best way to find the real answer is to go straight to the manufacturers. Most of the large manufacturers are part of an organization called the Tile Roofing Industry Alliance.
Their official response to the proper cleaning procedure is below:
“The cleaning of tiles with pressure washers is a common practice as regular roof maintenance. Since roofs are slippery when wet, the work should be performed by a qualified roofing professional. The use of diluted chlorine can be used to help remove the final algae that might be present, but we have seen just plain water used as well. The pressure washer should not be above 1300 psi as it can create surface wear. The dirt, algae or moss that grow on the surface of the tiles are not affecting the condition of the tiles. It is more an aesthetic issue that homeowners wish to remove.”
5 of the Top Manufacturers of concrete tile roofs have also released specific directions for their own products, however they are all consistent in saying you can use a pressure washer at around 1200-1300 PSI or you can soft wash with sodium hypochlorite.
Eagle Roofing Products
Crown Roof Tiles
Westlake Royal Roofing Solutions
Redland Clay Tile
Ludowici Roof Tile
Can You DIY This? Probably Not.
Walking on a roof with hoses is extremely dangerous—slipping is a major risk. Most homeowner pressure washers operate at 2500+ PSI, which exceeds manufacturer guidelines and could void your warranty.
Improper cleaning techniques can cause water intrusion or permanent damage to your tiles.
What about hiring a contractor?
How does Spring Clean approach these types of roofs?
At Spring Clean, we've developed a safer and more effective method for cleaning concrete tile roofs, especially for homeowners in the Pacific Northwest, where heavy moss and pine needle buildup are common.
Our Two-Step Concrete Tile Roof Cleaning Process
Step 1: High-Pressure Air Cleaning
Instead of using high-pressure water, which can force moisture under the tiles, we use a high-pressure air system to blast out pine needles, dirt, and loose debris from between the cracks.
This dry cleaning method helps:
Prevent water damage and leaks
Preserve the tile's protective coating
Improve the effectiveness of the next step-soft washing
Step 2: Soft Wash Treatment
Once the roof is cleared of debris, we apply our low-pressure soft wash solution, which consists of sodium hypochlorite (bleach) and a specialized surfactant. This treatment:
Kills moss, algae, and lichen at the root
Breaks down organic stains over time
Provides long-term protection against future growth
Unlike pressure washing, which only removes surface-level moss, our soft wash treatment penetrates deep into the roof's pores, allowing the remaining organic growth to naturally break down and wash away over the next several weeks.
Why This Method Works Best
Safer for Your Roof - No risk of tile damage or water intrusion
More Effective - Eliminates moss at the root, preventing regrowth
Long-Lasting Results - Keeps your roof cleaner for longer
Eco-Friendly Approach - Reduces excessive water use and runoff
Protect Your Investment—Contact Spring Clean Today!
If your concrete tile roof has pine needle buildup, moss, or algae, it's time for a professional cleaning. Our high-pressure air cleaning and soft wash treatment ensures long-lasting results without damaging your tiles.
Pricing: Cleaning costs $0.50 - $0.75 per square foot on average.
Call Spring Clean today for a free consultation and keep your roof looking great for years to come!
