Is moss on your roof harmful?

A mossy roof before it has been cleaned

For many homeowners, the appearance of roof moss is an unwelcome one. Not just because of the way it looks, but because of the perception that a build-up of moss on the roof of their home means a host of issues are just around the corner. But is moss on your roof really that harmful? Here at Roofline Solutions Home Improvements Ltd , we’ve looked into the issue, so read on, as our findings are featured below.

What is moss and why does it form on my roof?

Moss is a species of plant, usually green in colour, that thrives in moist, shaded areas. Many species of moss have no flowers, seeds or roots. Moss’ lack of roots means it requires a damp environment in order to grow. The tiles on your roof are moist and can be shaded by nearby trees, meaning conditions are ideal for moss to grow. Roofs accumulate leaves from nearby trees and other organic material too, which provide moss with the nutrients it requires to thrive.

Can moss on my roof be harmful?

Whilst there is some debate over the extent to which moss on a roof causes harm, moss build-up has the potential to cause a range of issues, which are covered below.

What if roof moss falls into my gutters?

Excessive amounts of roof moss can fall into the gutters, causing them to become blocked. This will inhibit your gutter’s ability to transport water away from your home, potentially causing them to leak. Leaking gutters can cause water to run down the side of your house, leading to the growth of mould on the inside and outside of your home. However, if your gutters are clogged, Roofline Solutions Home Improvements Ltd can remove moss and other debris from them as part of our gutter clearing service.

Does moss build-up present a slip hazard?

One issue with a moss covered roof is that it makes the surface very slippery when wet. This can be hazardous whenever you step foot on your roof, although how often do you spend time on there? For most people, time spent on their roof is likely very low, meaning moss’ potential as a slip hazard for the average homeowner is fairly limited.

Can roof moss cause structural damage?

As moss on a roof grows, it can cause the tiles to raise. The problem with raised tiles being that water is able to creep underneath them, leaving the roof rafters susceptible to rot. If too much of the rafter rots away, leaks may also occur, which can lead to costly repairs. However, the extent to which the moss can penetrate your roof deep enough to cause structural damage is debated. A small amount of moss is unlikely to cause this sort of harm, especially if it’s only been there for a brief period of time. In humid, well-shaded areas, where moss can easily accumulate, such issues are likely to develop more quickly.

Can it damage roof tiles?

A roof after moss clearance service has been carried out Not on its own, however if water is present on your roof tiles and it freezes, there is a chance of cracks occurring to the tiling. And because moss holds water, by removing it from the roof you are reducing the likelihood of cracks occurring to your tiles during cold periods.

Treating moss build-up on your roof

If you’d like to remove any moss which has found its way onto your roof, you can do so in the following ways:

  • Spray the moss with a garden hose and scrape it off the roof using your hand. Using your hands instead of a tool will reduce the risk of damaging your roof tiles.
  • There is a range of moss removal products which you can apply to your roof. Alternatively, there are household solutions you can use, such as vinegar which has been diluted with water. Baking soda has also been known to destroy moss.
  • Avoid power washing the roof as damage can occur to the tiles, especially if someone is treading on the roof whilst power washing.
  • Clay tiles are also very fragile, meaning removing an accumulation of moss on a clay tile roof may cause more harm than good if it’s not done extremely carefully.

At Roofline Solutions Home Improvements Ltd , we offer a moss removal service. We have found that the most effective method is to remove the moss from each individual tile using wire brushes. Once all of the moss has been removed we will spray a biocide chemical treatment on to the tiles, which will keep your roof moss free for 3 years. We will replace any tiles that get broken or damaged in the process of cleaning.

Preventing the build-up of moss on your roof

  • Perform regular inspections of your roof, especially if it receives very little sunlight or you live in a moist area. Bear in mind that if there is a build-up of moss, the earlier you remove it the easier the removal process will be.
  • As moss thrives in shaded conditions, keeping any nearby trees trimmed will increase your roof’s exposure to sunlight, making conditions more difficult for moss to grow. Keeping nearby trees trimmed should also reduce the number of sticks and leaves that make their way onto your roof, meaning moss has fewer nutrients to consume.
  • Keep your gutters clear from leaves and other debris – Roofline Solutions Home Improvements Ltd install the Hedgehog Gutter Brush which can help with this.

For more information on how you can maintain your roof, or for any replacement roofline components, such as guttering, fascias & soffits, get in touch with Roofline Solutions Home Improvements Ltd today. A member of our friendly team is available to call on 01252 852 336 or you can send us an online message.