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TOPIC: Cleaning Your Metal Roof

cleaning with bleach?

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I own a pressure washing service. Typical cleaning solution for a shingle roof is a mixture of bleach, water, and trisodium phosphate or sodium hydroxide. Is bleach safe for colors, such as red or green? Some of my customers have aske me to clean their metal roofs. I want to be sure and not commit any no-no's. Thank you
Guest User

1/21/2006
That is the solution that we recommend on both our painted and granular products but we have conditions on the pressure. It is always best to try it first and if possible contact the manufacturer. As a side note, we have cuonsumers looking for cleaning companies in Texas. If interested please contact me directly at [email protected]
Allan Reid
Dura-Loc Roofing Systems, Inc.

1/23/2006
I've heard five parts water to one part bleach, and I've heard 3:1. If you're just using water and bleach, what's the best ratio?
Guest User

7/23/2007
You can experiment to find what works but always try a small test area first to make sure the roof finish is not damaged by the cleaning solution. Todd Miller
Todd Miller
Isaiah Industries, Inc.

8/4/2007
I own a roof cleaning company in Maryland and we usually use bleach and a product called power house from a company called Sun Brite Supply, as a surfactant. The power house tends to foam up a bit holding the solution in place longer so it can kill the mold and mildew. It also helps to lift it from the surface so it can be rinsed free easier. One of the most common growths on roofs is Gleo Caspa Magma and often looks like a black stain on the surface. Regardless of what your trying to remove from the roof you should use the least amount of pressure possible with the weakest solution of cleaner. We generally use less than 600 PSI when cleaning roofs.
Henry Bockman
One Step Above The Rest!

2/3/2008
Thanks Henry. Todd Miller
Todd Miller
Isaiah Industries, Inc.

2/6/2008
Does that pressure setting (600PSI) apply to metal roofs as well?
Guest User

4/18/2008
This is rather unpredictable based upon the exact roof, paint finish, and condition. Your goal will be to remove the dirt but not the paint. You may need some trial and error. Todd Miller
Todd Miller
Isaiah Industries, Inc.

4/21/2008
I was afraid you'd say that... I'm more "error" than "trial" usually. Our galvalume roof has been up for 21 months and is covered with mold/mildew. I've been able to pressure wash from the ground, but, due to the slippery nature of wet metal, I'm avoiding going up to the peak... even with 4/12 pitch. Do you recommend one of the sole/grip products out there to keep me on the roof, or, a technique to clean from afar? Thanks again!
Guest User

4/22/2008
If you could use a bucket truck, that would be best. Always tie yourself off when on the roof, per OSHA. Cougar Paws and Korkers are names of two of the footwear products you mentioned. Todd Miller
Todd Miller
Isaiah Industries, Inc.

4/27/2008