Use a sprayer attached to garden hose that s filled with equal parts chlorine bleach and water.
Pressure clean roofs.
Time and care must be taken to wash every inch of a roof including gutters and drainpipes but the end result is well worth it.
There is also a risk of flooding to the loft space.
This is the best way to clean a roof if you have asphalt shingles.
This is because the water comes out too forcefully and can damage the material.
Instead spray down the roof with a cleaner that kills mold and moss or apply a 50 50 mixture of bleach and water in a pump sprayer and let the moss die on its own.
In most cases all you need is pressurized water but sometimes you may need a chemical cleaner for especially tough spots.
Most contractors don t recommend pressure washing or power washing a roof.
Metal roofs are relatively easy to clean with patience.
A home cleaner can be made with a quart 95 l of standard laundry bleach and a gallon 3 8 l of water.
Start with a medium pressure spray pattern and adjust from there accordingly.
Instead soft washing with a garden hose is least likely to chip dent or crack the tiles or panels.
Use low pressure to spray it clean the power of a pressure washer can damage the shingles on your roof so it s important that you select the proper spray tip.
As stated by several roof tile manufacturers and the uk s trading standards organization pressure washers can damage roof tiles strip the surface granules from the tiles and shorten tile life expectancy.
High pressure tile cleaning is a very important step in a roof restoration.
While specialized eco friendly roof cleaners are available they are a little more expensive.
Optionally add cup 177 5 ml of a non ammonia heavy cleaner such as tsp trisodium phosphate for extra cleaning power.
Of laundry strength liquid chlorine bleach and water.
Read more about why pressure washing a roof is a very stupid thing to do.
Make sure to build up pressure.
Most important though is to take some safety precautions before attempting to clean to reduce the chance of injury.
Start off with a hot water pressure with a 40 degree tip.
Roof guard is able to provide roof cleaning for a range of roof varieties and materials from concrete and terracotta to polycarbonate and metal.
This is very effective at getting rid of algae and mildew both of which often grow on metal roofs.
Each of these methods has their strengths and their own shortcomings.
You only need low pressure on metal roofs as it is enough to disturb and clean them.