The moss on your roof isn’t just an eyesore; it actually can be a substantial danger to the structural integrity and health of your roof. This article will go over how and why moss grows on roofs, explain the removal process using proper chemicals and equipment, discuss the benefits of professional moss removal, provide the average cost and explore the factors that affect the cost of removing moss.

How Moss Grows on Roofs

Roofs, especially in places like North Vancouver and the more broad Lower Mainland, where we are, are particularly sensitive to moss growth because the wet and moist conditions are very conducive to moss growth. 

Even though the dense vegetation and frequent rainfall provide great benefits to us and our world, it also creates the ideal environment for moss to settle and germinate. 

That combined with the shaded areas and higher moisture levels on roofs provides the perfect environment for moss to grow. Our cool and damp climate, especially in the wintertime, in North Vancouver fosters conditions conducive to moss growth, making regular moss removal a critical aspect of roof maintenance in this region.

The Roof Moss Removal Process:

Effectively removing moss from a roof involves a meticulous and multi-step process that prioritizes both efficacy and the safety of the surrounding environment.

Step 1 – Preparation

Before you begin the moss removal process using any chemicals, it’s very important to prepare your roof, house, and property. This can involve watering plants and the property around the roof to safeguard them from any products that are used during the cleaning. This is especially important if you have lots of plants or plants that are more susceptible to chemicals. 

You should also use a blower on the roof to remove any debris and larger contaminants to ensure you’re able to deep-clean and create a receptive surface for the chemical application.

Step 2 – Product Preparation

The choice of product is very important when considering moss removal. We. like most professional pressure washers, use a 12.5% sodium hypochlorite, mixed with water to the strength necessary for the specific conditions of the roof. Factors such as the extent of moss infestation and the overall dirtiness of the roof influence the selection and dilution of the cleaning solution. 

We also use a surfactant in addition to our solution to increase our product’s dwell time and cleaning efficacy.  This roof-specific approach ensures that we are able to fully clean the roof and remove any moss for good.

Step 3 – Application with Softwashing System

The application of the chosen product is VERY important. Rather than using a pressure washer,  we use a system called “soft washing”, which is necessary for roof cleaning. This system utilizes low-pressure nozzles, hoses, and wands, which mitigate the risk of causing damage to the roof that high-pressure washers very likely will inflict. 

This careful application ensures that the cleaning agents penetrate the moss, effectively breaking it down, without the possibility of dislodging shingles or destroying the protective granulation of your roof.

Step 4 – Dwell Time and Retreat, as Needed

After the product is applied, allowing it to dwell is a critical step in the moss removal process. The dwell time allows the cleaning agents to break down the moss and other organics thoroughly. Depending on the severity of the moss infestation, retreatment may be necessary at a higher product strength. 

This step-by-step approach, combining precision in product application and the use of a soft washing system, ensures a comprehensive and safe moss removal process that prioritizes the health of the roof and the surrounding environment.

Benefits of Professional Moss Removal from a Roof

Eradication of Moss

Professional moss removal ensures the complete eradication of moss from your roof. Many homeowners lack the specialized equipment and expertise required for thorough moss removal. Professionals employ advanced techniques and industry-grade solutions to address moss at its root, preventing regrowth and safeguarding the structural integrity of the roof.

Increased Time Savings

Attempting moss removal without proper equipment can be time-consuming for homeowners. What might take a homeowner an entire day could be efficiently completed by professionals in a matter of hours. The efficiency stems from the use of specialized tools and techniques, ensuring a swift and effective moss removal process without compromising quality.


Roof cleaning involves working at heights, presenting a safety risk for homeowners attempting the task themselves. Professionals are trained in proper safety protocols and have the necessary equipment, such as harnesses and scaffolding, to navigate the heights safely. 

moss removal from roofs

Choosing professional moss removal not only ensures a thorough job but also eliminates the risk of accidents associated with DIY attempts.

How Much Does Roof Moss Removal Cost?

On average, it will cost between $600 and $1,100 to remove moss from your roof, which is approximately the price of a full roof cleaning. This price can vary greatly depending on a variety of factors, including;

Roof Size and Slope

The size and slope of the roof are key factors influencing the cost of moss removal. Larger roofs or those with steeper slopes may require more time and effort, affecting the overall cost of the service.

Severity of Moss Infestation

The extent of moss infestation plays a significant role in determining the overall cost. More severe infestations may require additional treatments and a more comprehensive approach, impacting the total expense.

Chemical Removal Method

The method chosen for chemical removal also affects the cost. Different chemical solutions and application techniques may vary in price, and the choice depends on factors such as the type of moss and the desired level of effectiveness. Professionals assess these factors to determine the most suitable and cost-effective approach.

DIY Moss Removal Tips

1. Gentle Cleaning Methods

When tackling moss on your roof, avoid high-pressure methods like pressure washing. High-pressure water can damage roofing materials and dislodge protective granules, leading to potential long-term harm. Opt for gentler approaches to ensure moss removal without compromising the structural integrity of your roof.

2. Avoid Agitation Techniques

Resist the temptation to scrub or brush moss off your roof vigorously. Agitation, even with soft brushes, can dislodge shingles or damage granules, causing more harm than good. Instead, opt for non-aggressive methods that target the moss without compromising the integrity of your roofing materials, like chemical application.

3. Use Caution When Applying Chemicals

If you choose to use chemicals for moss removal, exercise caution around the plants near your home. Some chemicals can be harmful to vegetation, so it’s essential to water the plants thoroughly before application. Additionally, consider covering them with plastic sheeting or tarp to protect them from any overspray. This precaution ensures that your landscaping remains unharmed while effectively addressing the moss issue on your roof.

By following these DIY tips, homeowners can take proactive measures to address moss growth while safeguarding the longevity and health of their roofs.

Let’s Get That Moss Off Your Roof!

Regular maintenance and getting rid of the moss on your roof are critical to the integrity and aesthetic appeal of your roof. Chemical treatments, when administered professionally, offer a fast and easy solution to moss infestations that otherwise appear impossible. 

If you’re in North Vancouver, or anywhere else in the Lower Mainland, get in touch with us today about restoring your roof to its former glory! Or if you have more questions, our FAQ page is a fantastic resource to learn more about roof cleaning and moss removal. Regular roof cleanings are a great way to maintain the structural integrity and visual appeal of your roof, reducing the need for expensive repairs.