How to Remove Lichen from Roof Tiles

Lichen is a combination of algae and fungi that can grow on roof tiles, particularly in areas with high humidity or frequent rainfall. While lichen may not immediately damage your roof, it can trap moisture, cause discolouration, and accelerate tile deterioration over time. Regular removal is essential to maintain the longevity and appearance of your roof. This article provides a detailed guide on how to effectively and safely remove lichen from roof tiles.

Why Remove Lichen from Roof Tiles?

1. Prevent Moisture Retention: Lichen holds moisture against roof tiles, which can lead to the growth of moss, mould, or algae and increase the risk of water infiltration.
2. Preserve Aesthetic Appeal: Lichen often causes unsightly stains, diminishing the overall appearance of your home.
3. Extend Roof Lifespan: Prolonged lichen growth can erode roof tiles, particularly porous materials like terracotta or concrete.
4. Ensure Proper Drainage: Lichen can obstruct water flow, potentially causing pooling or damage to gutters.

Tools and Materials Needed

• Soft-bristle brush or scrubbing pad
• Garden hose with a spray nozzle
• Pressure washer (optional, with caution)
• Bucket
• Non-toxic lichen remover or diluted bleach solution
• Safety gear (gloves, goggles, non-slip shoes, safety harness)
• Ladder or scaffolding for roof access

Step-by-Step Guide to Remove Lichen

Step 1: Inspect the Roof

Start by assessing the extent of lichen growth and checking for any damaged or loose tiles. Make necessary repairs before beginning the cleaning process to avoid further damage.

Step 2: Prepare the Cleaning Solution

Mix a lichen remover solution according to the manufacturer’s instructions. Alternatively, you can create a DIY solution by mixing 1 part household bleach with 10 parts water. Ensure the solution is safe for your tile material and surrounding plants.

Step 3: Apply the Solution

Using a garden sprayer or soft brush, apply the cleaning solution directly to the areas with lichen growth. Let it sit for 15–30 minutes to break down the lichen. Avoid letting the solution dry completely, as this can make removal more difficult.

Step 4: Scrub the Lichen

Using a soft-bristle brush or scrubbing pad, gently scrub the tiles to loosen and remove the lichen. Avoid using hard-bristle brushes or abrasive tools that may damage the surface of the tiles.

Step 5: Rinse Thoroughly

Rinse the roof tiles with a garden hose or low-pressure washer, ensuring all cleaning solution and debris are removed. If using a pressure washer, keep the pressure below 1500 PSI and use a wide-angle spray tip to prevent damage to the tiles. Work from the top of the roof downward to avoid water seeping under the tiles.

Step 6: Inspect and Repeat if Necessary

After rinsing, inspect the roof for any remaining lichen. Reapply the cleaning solution and repeat the scrubbing and rinsing process if needed.

Preventing Lichen Growth

1. Install Copper or Zinc Strips: These materials release ions when it rains, inhibiting the growth of lichen, moss, and algae. Install them along the ridge of the roof for maximum effectiveness.
2. Trim Overhanging Branches: Reduce shade on the roof by trimming nearby trees to improve sunlight exposure and airflow.
3. Regular Roof Maintenance: Clean the roof periodically to remove debris, dirt, and organic matter that encourage lichen growth.
4. Ensure Proper Drainage: Keep gutters and downpipes clear to prevent water pooling on the roof.

Safety Precautions

1. Work in Dry Conditions: Avoid cleaning the roof when it’s wet, as tiles can become slippery.
2. Use Safety Gear: Always wear gloves, goggles, and non-slip shoes. A safety harness is essential for working on steep or high roofs.
3. Avoid Harsh Chemicals: Use non-toxic cleaners whenever possible to protect your tiles, health, and the environment.
4. Consider Professional Help: If your roof is steep, fragile, or heavily infested with lichen, hire a professional roof cleaning service to ensure safety and effective results.

When to Call a Professional

Removing lichen from a roof can be physically demanding and potentially hazardous. If you are uncomfortable working at heights or the lichen infestation is extensive, consider hiring a professional roof cleaning service. Professionals have the tools, experience, and safety equipment to clean your roof thoroughly without causing damage.