Guest User
1/29/2018
Do metal roofs need to be washed?
Todd Miller
Isaiah Industries, Inc.
1/29/2018
Generally, no. My metal roof has been on my home since 1996 and has never remotely needed washing or cleaning. That said, there are different finishes available on metal roofs as well as different climates and weather conditions. For example, if trees drop sap on the roof, that sap can really hold dirt and even support biological growth. This will be most noticeable on a light colored roof. My suggestion, if you have a metal roof and feel it may need cleaned is to contact the manufacturer and see what they say as far as how it can be cleaned. If you're anticipating a metal roof and wondering if it might sometime need to be cleaned, again, I will refer you to the manufacturer so you can describe your home's situation and see what they say.
Chet Hingle
3/16/2018

Hello, my company washes roofs and had the misfortune of slightly damaging a Galvalume roof. On portions of the roof, our cleaning chemicals turned it
a gray color. Is there a chemical to take that grey out and return the Galvalume back to its original color? Thanks

Eric Novotny
An informed customer is the Best Customer!
3/16/2018

Any chance you can post a picture of the damage?

Once the Galvalume finish is changed, I don't know of any non-factory processes to bring it back.

Cherri Prevatt
5/4/2018

We have black mold on our metal roof. It is colored metal (white). We don't have any trees over the roof. We are hiring a pressure washing person to clean it. He plans on using pool liquid chlorine on it to clean. Will this damage our roof? And he also said that we will need to have it cleaned every few years.
This will cost about $700 this year, and about $400 every year after that.
Any advice?

Eric Novotny
An informed customer is the Best Customer!
5/4/2018

I would contact the metal roof manufacturer first.

There are a myriad of roof/house wash products that work quite well and can be bought over the counter.

I would not apply pressure to the roof in this case. It is massively over specified and often inappropriately applied. That is a bad combination.

Todd Miller
Isaiah Industries, Inc.
5/4/2018

I agree with Eric. I would also avoid Chlorine ... if a chemical cleaning is necessary, look at a combination of water, detergent, and TSP. There are also products like RoofWash and Wet and Forget that may work.

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