The Best Way To Clean A Roof

What is the best way to clean a roof?

 “What is the best way to clean a roof”?  Let’s start the article with a big bold Bleach, Soap and Little or No Pressure!   Period, end of story.  I write these blogs every now and then because I start seeing the old saw about bleach being bad for roofs starting to emerge again.  My job is to write enough of these articles to kill that myth.    I also wrote about it here and here  The bottom line, and the only thing any consumer needs to  know, Let’s go bold again!- Bleach, Soap and Low Pressure.  It  is the only method recommended and  allowed if you are going to clean you asphalt shingle roof.  I shot a quick roof cleaning video to show you an example our low pressure process.   We use bleach and soap and safely clean hundreds of roofs each year.  

Roof Refresh is one of the older roof cleaning companies here in the Raleigh area.  We have been washing roofs for the better part of 13 years and have watched other companies come and go..   A vast majority of the companies that  died off, had a tendency to use  pressure washers when cleaning a roof.  Use a pressure washer, ruin a few roofs, get some bad reviews or claims filed against them and poof, they quietly disappear. 

Staying current with the roofing industry

Our success is based on two factors:  First, we do our best to provide customer service that goes above and beyond expectations.  A lot of companies have forgotten about customer service in this fast paced world.    Second, we have stayed current on the goings on in the roofing industry.  Shingle manufacturers are always improving products, revising  technical bulletins and standards  to ensure the correct installation of their shingles.  Roofers attend ongoing classes in order to be able to sell the shingles and any warranties that may come with it. Manufacturers are always competing to come up with a better look, a stronger mat, more algae resistance and longer shingle life.  

Can you guess what has not changed?  If you said the method of cleaning these shingles, you would be correct. Long before we started removing algae from roofs, shingle manufacturers endorsed the use of bleach, soap and low pressure  for roof cleaning.  They understand that  Algae and moss are not a good thing to have on your roof.  Cleaning it correctly is very important.

The term “low pressure”

What is low pressure roof cleaning?  Companies define low pressure a lot of different ways.  It means  safely cleaning the roof without blasting all the granules off your shingles.  Using a pressure washer can break the bond between shingle tabs.    Most professional roof cleaners use 12-volt, battery operated pumps, or the newest air diaphragm pumps.  Using these pumps allows the detergent (bleach / soap) to be dispersed on the roof  like a mild rain event.   Garden hoses are then used to rinse the roof.   My company uses the term “Zero Pressure”.  Yes, it is a misnomer, but it gets the point across and has been a successful catch phrase for us.  

Redefining low pressure?

The opposite of low pressure roof cleaning?  Potential customers see roof cleaning  companies that use the term “low pressure roof cleaning” incorrectly every day.  Defining low pressure for them means telling you a couple of things: Their pressure washers are  throttled down, or that they hold the pressure washing wand high and away from the shingles.  “Our roof  machines have been “specially modified” to lower the pressure”, is the best one I have read.

Terms like “Eco friendly” and “Green Cleaning” are their favorite.  All the while they are blasting away with pressure washers and destroying your roof.  

Who should you trust to clean your roof?

Trust a professional roof cleaner who carries good insurance and uses the methods recommended by the shingle manufacturers.  We will always tell our customers we use bleach and soap and no pressure to clean a roof.  Ask for a Material Safety Data Sheet (MSDS).  Most of the pressure washer types us Sodium Hydroxide and claim it is Eco Friendly.  Truth be told, it is a very dangerous chemical.  A good indicator used to be reviews.  

Google reviews are very informative, sites like Angie’s List, not so much.  I use Angies List as a quick example because they are a Pay To Play site.  Contractors with the most advertising dollars get the attention.  They also allow companies that pressure wash roofs to post articles on their site.  I guess to be fair, they allow both sides to post articles.  So, we always hang up and block their telemarketing calls.


Roof Refresh is a zero pressure roof cleaning company that uses bleach and soap to professionally clean your roof.  Call today for a free estimate.  




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