If the algae have only damaged a couple of shingles then repairs can fix the problem.
Roof damage from algae.
If your home has a highly reflective roofing system algae growth can affect the roof s ability to reflect sunlight.
Roof algae are signs.
See lichens on roofs for an example.
If you re trying to sell your home you may run into issues if you have roof algae.
However if the algae have penetrated deep into the roof affecting most of the roofing tiles or if your roof is old and in need of a repair generally then a roof replacement is probably more suitable.
8 ways roof algae can affect your roof appearance.
They re likely to damage the shingles just be sure to wet your foundation plantings first and rinse everything in clean water when you re done.
No pressure washers please.
Moss can damage shingles especially asphalt and wood shake shingles.
If your roof serves as an energy efficient system this could end up costing you additional money in terms of heating or cooling bills.
Algae and lichen.
The less expensive solution is to spray wash the roof with a 50 percent mix of water and bleach to get rid of the algae.