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.
How to clean slate roof shingles.
No pressure washers please.
Such harsh chemicals are incompatible with the copper components of your slate roof.
Sunlight and warm weather will ensure the cleaning solution dries too fast to be of any use.
Then spray the cleaner onto the shingles photo 1.
Punch a hole into shingle from the back.
Start at the lower portion of the roof moving up as you clean each lower section.
Step 2 replacing the shingles.
Regular roof cleaning is critical for your roof as slate is easy to cleave and water absorbent.
That ll prevent the cleaner from drying out too quickly.
Step 1 choose a cool and overcast day.
Limit cleaning to removing organic debris and delaminated slate flakes from valleys snow guards gutters and the area behind the chimney.
A vinyl leaf rake can clean harder to reach spots.
That way you always stand on dry surface and reduce the chance of slipping.
Slide the replacement shingle into place.
When cleaning a slate roof don t use chemicals like ammonia or chlorine bleach.
Asphalt shingles are easy to install last anywhere from 10 to 50 years depending on the type and are less expensive than other roofing materials such as slate tile and metal.
In addition choose a day with little wind so that when you spray the solution it stays on your roof 1 x research sourcestep 2 perform maintenance on your roof.
The day you perform deep cleaning on the shingles should be cool and overcast.
Hook the nails and pull them out.
The trick to doing this successfully is applying the solution with a garden type sprayer and letting it sit and reapply and reapply and reapply.
Cleaning roofs is slippery work.
Use the sprayer to saturate a strip 3 feet high x 10 feet wide.
Before you begin it s important to repair loose shingles and flashings to minimize roof damage.
The more applications and sitting time the better.
Wait about 20 minutes then rinse.
Before applying the cleaner spray the roof with water to cool it down.
You want to keep it wet once you ve begun.
Spray the cleaner on a section of roof and let it sit for about 15 minutes.
Use heavy rubber gloves to scoop up material in areas you can safely reach.
If a slate shingle needs to be replaced use the slate ripper a 2 foot piece of cast steel that includes a blade and a hook for the removal of slate nails and broken shingles.