How do I stop moss growing on roof shingles and tiles?

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Moss and algae growing on roof shingles and tiles can be unsightly, not to mention damaging.

The thing is:

Left to grow and embed itself, moss on roof tiles can cause thousands of pounds of damage. Eventually, it will cause your roof to become unstable and degrade.

At this point, you’re probably wondering:

What can you put on your roof to stop moss growing?

You’ve come to the right place!

Read on to find out how to stop moss from growing on your roof.

How is moss on the roof harmful?

Pitched roof covered with moss

The growth of moss on roof tiles or shingles can be problematic for several reasons.

Let’s take a closer look at the main ones.

Water retention

Moss has a sponge-like structure that absorbs and retains water. When it grows on your roof, it can hold moisture against the surface, preventing it from properly drying. This prolonged moisture exposure can lead to the degradation of the roofing material over time.

Roof damage

As moss expands and spreads, it can penetrate between and underneath the roof tiles or shingles. This can loosen or lift them, creating gaps that allow water to seep beneath the roofing material, making it more susceptible to damage from wind, storms or other external forces. Over time, this can result in leaks, water damage and the need for costly repairs.

Reduced lifespan of the roof

When moss is left unchecked, it can accelerate the deterioration of roof tiles or shingles. The constant presence of moisture and the associated organic growth can degrade the material more quickly, reducing its lifespan and necessitating premature replacement.

Aesthetic concerns

Many of us have this mental picture of moss-covered roofs as picturesque and dreamy. And they can certainly be that – in a Hollywood movie.

But the truth is:

In the real world, moss-covered roofs are often visually unappealing. The greenish growth can give the roof an unkempt appearance, which may negatively impact the kerb appeal of your home.

How to treat moss on roof shingles or tiles

Roof tiles with moss growth

Now that you know exactly why moss growth is bad news for your roof, let’s see what you can do about it. We have a dedicated guide on the topic we recommend that you check out.

In a nutshell:

If the moss growth is not too severe, you can get rid of it by softly brushing it away. We recommend that you use a long-handled brush and exercise caution while walking on the roof.

Applying moss killer is another viable option, but we should note that these chemicals can potentially contaminate groundwater. So, if you decide to go down that route, always wear suitable protective clothing.

If there’s considerable growth or working at heights isn’t your cup of tea, you can always ring the professionals.

How to stop moss growing on your roof

Now that you’ve successfully removed any existing moss or algae from your tiles or shingles, you want to make sure these types of organisms stay away from the roof for good.

The good news is:

There’s a quick and easy way to do this.

Here’s the scoop:

Moss or algae growth is easily treatable with zinc or copper strips. For their inexpensive price and low environmental impact, copper strips are the most effective and cheapest way to do this. Copper is the third most recycled metal in the world, after iron and aluminium.

Add a 2-inch thick strip of copper across the ridge of your roof, as close to the pitch as possible. This will protect roof shingles and tiles from growing moss.

How exactly?

Moss growth on a roof

Check this out:

When it rains, the copper salt will be washed down the roof from the strips you’ve fitted and will coat the roof. This then prevents moss and algae from growing.

If your roof is larger than average, you might need to fix more than one strip. In this case, add a copper strip at the midway point down the roof, too.