Algae and moss grow best in shaded, damp areas and are able to cause significant and costly damage to your roof. The UK, as a whole, only averages approximately 1493 hours of sunlight a year. Couple that with the average yearly rainfall which is 1,154mm according to the UK Met Office, and you are left with perfect conditions for moss to thrive under. Moss in itself is harmless as it does not produce any dangerous fumes or spores nor is it heavy enough to do any structural damage on its own. The danger of moss lies in its ability to retain moisture the very reason that regardless of how quaint it may look, you need to remove it from your roof as soon as possible.
Why is moss growth bad for your roof?
While moss may look beautiful in a luscious, green garden, the tiny roots are ace at finding gaps in roof shingles to latch onto which can compromise the roof seals, causing leaks, shingle loss and wind intrusion. When on your roof, moss acts like a sponge, constantly absorbing moisture which will result in your roof being wet all the time. The problem is amplified by the high rainfall figures in the UK as your roof really has little to no chance of ever getting dry. With constant moistures comes the possibility of rotting wooden components which will drastically impact the structural integrity of your roof. Moss on your roof is more than likely going to attract a large selection of insect and bird life which, apart from defecating your roof can also cause the moss to be dislodged from the roof surface and dropped into gutters and downpipes, causing blockages which can lead to costly repairs.
How to remove moss growth from a roof
The easiest way to remove moss from a roof surface is to brush it off with a stiff brush. It is usually not too difficult to do, unless of course you have a fear of heights. Try using a long-handled brush and be very careful when walking on top of your roof (always seek professional help if you are unsure at all about the structural integrity of your roof or working at heights. Safety first and always). Another way to rid your roof of moss is to use a commercial moss killer which, although very efficient, could end up contaminating the groundwater. Rather use diluted bleach which is less hazardous to the environment though the runoff can still damage surrounding plants. While a high-pressure cleaner can be used to remove plant growth and dirt from a roof it has to be done with extreme care as a powerful water jet can damage asphalt shingles.
How to prevent moss re-growth on your roof
The first step to take in preventing moss growth on your roof is to try increase the amount of sunlight it gets. Although this could be difficult with the typical UK weather, you can aid the process by trimming overhanging tree branches that cast constant shadows on the roof. All debris such as leafs and sticks should be removed as soon as possible and gutters must remain well-maintained to ensure that water flows off the roof as fast as possible. A lot of roofers recommend the installation of zinc strips close to the peak as zinc becomes a natural moss killer when it comes into contact with rain water. Copper strips can also be used instead of zinc with a very similar effect. IKOpro Algae and Fungi Remover can also be used on all outside surfaces, including brickwork, tiles, slates, facades, flooring, glasswork, wood, plastics, bitumen shingles and bituminous roofing.
Despite how you choose to address the moss problem on your roof, it is important to always put your own health and safety first. If you are doubtful of your own ability to perform the required tasks, rather enlist the help of a professional roofing company that will be able to carry out the job swiftly and safely while you remain with both feet planted firmly on the ground.
written by Jackie Francis