Damp and shaded environments are havens for moss growth, and thanks to the UK weather, that can include our roofs. Although in some cases a mossy roof can look appealing if left to grow it can cause both direct and indirect damage to your roof and the inside of your building.

Why does moss grow on roofs?

In the right circumstances, moss can collect on roofing extremely rapidly. Shaded areas which get exposed to damp are perfect conditions for moss. The way roofing collects rainwater makes the roof a prime place for moss growth.

In dry summers moss may dry out and go black, this does not mean it is dead though and will likely turn green and thrive again when it receives some moisture and go back to being an issue.

Does moss damage roof tiles?

Moss growing on a roof can directly reduce its longevity and structural integrity. It can result in leaks and damage to the inside of your building as well. Damage is caused in part due to the rhizoids of the moss. Rhizoids are what moss has instead of roots and they are a hair-like structure that anchors the plant to a surface.

Roof damage is also brought about due to the high length of time that moss can retain water. These two factors can cause the roofing materials to weaken and rot over time.

Though to some it may be visually appealing and rustic to have a mossy roof, it is important to understand that this can greatly reduce the lifespan and function of your roof.


Roof Moss

What will happen to your roof if you leave moss growing on it?

If moss is growing on your roof it can increase the porosity of the tiles, this means there is more chance of rainwater permeating through. Rainwater in your roof tiles can be especially problematic in winter where freezing temperatures can cause the water to expand and in some cases burst the tile. Alternatively, when it thaws it may leave the tiles pulled apart.

The rhizoids that moss uses to grow and anchor to surfaces can also cause cracks and fissures which can lead to leaks and further damage. Not only does this damage the roof tiles but can cause the rotting of any wood directly under the roof.

Moss can also negatively affect your guttering as over time the moss will fall off the roof and land in the gutters which can soak up water and weigh your gutters down. This can cause your gutters to sag and reduce their efficiency.

If you are looking to sell your house, a mossy and neglected looking roof can be off-putting to some and may reduce the desirability of your home.

Should you trim back plant growth from your home?

Cutting back plants around your roofing can limit and prevent further moss growth. For example, trimming tree branches that overhang on the roof will reduce the amount of shade, which will also reduce moss growth. 

Trimming overhanging trees will also reduce debris on your roof. Debris on the roof can increase shade and dampness on parts of the roof. More moss can also cause more debris to become trapped on the roof.



How to go about moss removal from the roof?

If done incorrectly, removing moss from your roof can end up causing even more damage than if it was left. This can be down to structural issues, and your roof possibly not being strong enough to support the weight of a person. If you need moss cleared from your roof it is important to seek the help of a professional who will inspect your roof and decide the safest and most effective course of action.

Another issue can stem from the cleaning products that are used. Normal household cleaning products can cause unsightly reactions on roofing. You can be sure that an experienced and trusted roofer will be using specially designed roof cleaners that will not cause staining.

There is specialist equipment which is necessary when it comes to removing moss from your roof. To not cause damage to yourself or your roof, it is recommended to seek the assistance of a professional.

If you are having issues with moss on your roof S&J Roofing Bath has all the necessary equipment and expertise to solve your roofing concerns. Contact us for further information and advice.