How To Clean Roof Tiles

A well-maintained roof is vital for a weatherproof home. Here at GPH Builders Merchants, we understand the challenge roofs (especially in the UK) can face, specifically with moss growth. This blog will guide you through effective methods for cleaning your roof tiles, including pressure washer and non-pressure washer options, along with safety considerations and when to seek professional help. 

Why Does Moss Grow on Roofs? 

Keeping your roof moss-free in the UK can be a challenge. The damp climate provides perfect growing conditions for moss. Frequent rain offers constant moisture, and moss thrives on damp surfaces because it absorbs water directly through its leaves. 

Shade is another enemy, as north-facing roofs or those overshadowed by trees stay damp for longer, creating ideal conditions for moss to spread. Windblown debris like leaves and twigs further contributes to the problem by trapping moisture and providing a breeding ground for moss spores. These spores easily land on the damp tiles and germinate, taking hold and spreading across your roof. 

Does Moss Damage Roof Tiles?

While moss itself isn't destructive, the thick layer it creates can wreak havoc on your roof. This persistent moisture weakens the tiles over time, making them more likely to crack and break. Additionally, dislodged moss can clog gutters, leading to overflows and potential water damage to your roof and walls. Even worse, trapped moisture under the tiles can eventually seep into the roof structure, increasing the risk of leaks and interior damage.

Looking for quality roof tiles that last? Head over to our roofing page to stock up on slates, fixings, nails and more! We recommend the fan favourite - the Del Carmen Spanish Heavy Slate for the ultimate timeless appeal! 

How To Clean Moss Off Roof (Pressure Washer Method)

Safety First: Pressure washers can be powerful tools, so prioritise safety:

1. Wear proper protective gear: Eye protection, gloves, sturdy shoes with good grip, and long sleeves are essential.
2. Secure your footing: Use a sturdy ladder with a spotter for added precautions!
3. Start low, work your way up: Begin at the bottom of the roof and work upwards in sections to avoid spraying yourself with debris.
4. Maintain a safe distance: Hold the nozzle at least a foot away from the roof surface to avoid damaging the tiles.

Cleaning with a Pressure Washer:

• Choose a low-pressure setting: A wide fan nozzle with a low-pressure setting (around 1,000 psi) is ideal for roof cleaning. Higher pressures can damage tiles!
• Start with a test area: First, test the pressure and spray pattern on a small, inconspicuous area of the roof.
• Loosen the Moss: Use a gentle sweeping motion with the pressure washer nozzle to loosen the moss growth. Avoid concentrating the spray in one spot for too long, as this could damage or crack the tile. 
• Clear the Debris: Once loose, use the pressure washer to carefully wash away the moss and debris towards the gutters. Be mindful of not overloading the gutters with debris.

Important Note: While pressure washers can be effective for moss removal, they should not be used for general roof cleaning. The high water pressure can damage tiles or dislodge protective granules.

(Non-Pressure Washer Method)

For those uncomfortable or without access to pressure washers, a safe and effective alternative exists:

• Choose a Dry Day: Moss is easier to remove when dry and brittle - avoid doing this in colder winter months.
• Loosen the Moss: Use a plastic scraper or a stiff brush with gentle strokes to loosen the moss growth. Be careful not to damage the tiles themselves with too much pressure.
• Clear the Debris: Once loose, remove the moss and debris with a gloved hand or a broom. Avoid using powerful tools that could damage the tiles.
• Moss Removal Products (Optional): Consider applying a moss removal product according to the manufacturer's instructions, this helps prevent future growth.

How To Clean Roof Tiles (General Cleaning)

Once the moss is removed, you can clean the roof tiles themselves:

• Prepare a Cleaning Solution: Mix a mild detergent solution in a bucket with warm water.
• Gently Wash the Tiles: Use a soft brush and the cleaning solution to remove dirt and grime. You can use a pressure washer on a low setting or hand wash for this step! 
• Rinse Thoroughly: Ensure all soap residue is rinsed away with clean water to avoid any stains and marks.
• Allow to Dry Completely: Leave the roof to dry completely before inspecting for any damage.

Cleaning your roof tiles regularly helps maintain their integrity and extend their lifespan. However, safety is paramount. If your roof is steep, high, or has fragile tiles, it's always best to consult a professional roofing contractor.

GPH Builders Merchants stock a wide range of roofing tools and materials, including pressure washers and moss removal products. Contact us today for expert advice and top-quality products to keep your roof in top condition!