Moss is a simple plant that does not produce flowers and grows in blankets in natural environments. Commonly seen covering trees, brickwork, stonework and roof tiles, many home owners see moss on their roof as a beautiful integration of their environment. If you are such an owner, keep your gutters and vents clean and enjoy your roof. Everyone else please read on.

Light growth of moss, and all lichen growth will certainly be trouble free.

Prolific (thick) growth of moss on roofs can severely damage the structural integrity of any type of roof tile.

Moss commonly thrives in environments that are damp and shaded. As it grows, it establishes 'roots' on your roof causing the beginning of roof tile degradation. Thick growth can lift up tiles and will often cause some tiles to crack and laminate.

Moss absorbs moisture from the environment as well as from rain. It retains moisture in itself and the tiles on which it is growing, which when frozen in the winter could eventually lead to the tile surface breaking away (laminating) when the ice forms.

In most cases, particularly with 'double lap' plain tiles this will not impact upon how well the roof functions or whether it leaks.

Love it or hate it, monitoring any moss growth is recommended by Tudor Roof Tiles. Do a regular visual inspection of the roof, particularly after the winter months, to ensure that any ventilation points are not blocked, and gutters are clear of debris and water is free flowing.

Removing Roof Moss
Tudor Roof Tiles believe that the best way to treat the moss growth is to prevent it. It’s much easier to remove new growth, than moss that has grown for 10 years.

Remove moss with a garden water hose and by hand scraping. Make a wooden long handled 'T' tool to gently dislodge the excessive moss growth. Using a pressure washer can cause severe damage to your roof, so stay away from the pressure washer!

Various chemical 'moss killer' treatments are also available which are low pressure sprayed on to the moss and cause the moss to die. These treatments do not damage the roof tiles, but can potentially harm wildlife and vegetation. Use with caution and remember that the spray itself, plus any liquid run off may drift/splash.

Of course the moss will take some days to die, and will not be dislodged the instant it is dead, it will be gradually removed by the weather over time.

Many roofing companies offer the chemical option as a 'cleaner' for moss covered roofs, usually combined with 'gentle' scraping of the tiles. When done responsibly and carefully, this is very effective.

Whilst on the subject of roof cleaning contractors, please try to stay away from the many 'ROGUE TRADERS' in this line of work. As always, do some research before handing over your money and your roof health.

Conclusion
Moss (and lichen) on a roof can make the roof look old and in keeping with it's environment, but it can affect the integrity of the roof tiles, and also disrupt water run off from valleys and gutters.

Prolific growths of moss will cause damage to the roof tiles, however, this is usually more of an aesthetic problem than a roof performance problem.

Prevention of moss growth is best done gently - and without power washing!