Roof Moss, Lichen, Algae

3 IMPORTANT reasons to clean your roof

Left to its own devices, algae, lichens, moss and other fungi as bacteria can build up on your roof and eventually take over. Many homeowners mistake algae for “roof mould.” The three main culprits that will damage your roof if left to grow are: -

1 - ROOF ALGAE

What is roof algae?

This simple plant-type organism does not comprise of leaves, roots or differentiated stems. Roof algae is considered to be a living thing that can actually eat up your roof tiles. It usually starts with a single spore carried in the wind from the local area. It then finds its way to your home’s roof; it is the most common growth on a roof.

Algae grows in water and damp areas in clusters.

It is influenced by environmental factors such as humidity, shade, climate and roof materials.

Algae likes moist and dark areas (especially under large trees and blocked gutters).

Algae has a protective sheath that stops the sun’s UV rays from harming it.

Roof algae hates the sun so north facing roofs where there is less sunlight, are more prone to the development of algae.

2 - MOSS

ARE MOSS & ALGAE THE SAME? Quite simply NO

Moss is a plant but reproduces through spores not flowers or seeds. Moss can build up into mounds and tufts on your roof. During wet times, moss is typically green with a spongy feel. Moss can turn greenish yellowish brown during the drier seasons. Moss will only thrive on damp or wet surfaces, and the moisture retained in the roof tile enables moss spores to establish themselves and become ingrained within the tile. Because it needs moisture to grow, moss prefers damp north-facing roofs where there is less sunshine. However, it doesn’t grow in submerged water. Like algae, it is carried in the wind from the local area, and in some cases, from animals.

What problems does moss cause?

Moss consume water and nutrients from any debris on your roof including damp leaves.

Moss thrives under over-hanging branches.

The build-up of moss on the roof can cause moisture damage and leakage.

Moss can damage the performance of roof tiles including causing the leading edges to lift, or even blow off in the wind.

We often find we need to repair or replace some roof tiles.

3 - STUBBORN LICHEN

Lichen is made up of both algae and fungi?

Unlike moss and algae, lichen needs sunlight to grow but also requires moisture, oxygen and nutrients. It isn’t classified as a plant, but a fungus that coexists with algae. It needs algae to survive. Lichen has three types: foliose, fruticose, and crustose. Lichen does look like moss in appearance, but it isn’t the same. What damage does lichen do to your roof?

Lichen traps humidity against the roof structures, resulting in gradual erosion to roof tiles.

Over time, roof tiles can become distorted or break.

Although lichen can take a long time to develop, it is the hardest to get rid of.

Lichen latches onto the protective layers of the tiles, which can come off when the lichen is removed, leaving holes.

PREVENTION of lichen on your roof is recommended instead of a costly roof repair.

CALL Prestige Exterior Cleaning Ltd ON 07399 811 325 FOR A FREE NO OBLIGATION QUOTATION