Washing the Roof

Jared: All right let’s go to Kevin in Kissimmee.

Kevin: I just got a question to ask about washing the roof. I’ve been told by somebody, a painting contractor was painting my neighbor’s house and he said, “Yeah, you should wash the roof. Pressure wash the roof down or whatever, because it builds up.” I’ve never heard of that one before. I mean…

Jared: Sure. What type of roof is it? Is it a shingle roof, tile, is it…?

Kevin: Yes, it’s shingle.

Jared: Shingle. Yeah, as for shingles you should never pressure wash. They have little granules on them and those granules are there for a reason and if you pressure wash the shingles, then all of those little granules are going to come off.

Kevin: That’s what I thought.

Jared: Yeah. Now it is a good idea to clean the roof. Understand that the reason why the roof gets dirty here in Florida is that there is fungus and algae that is growing on the roof. That is a plant system and it has a -- when it grows -- it actually has a root system that will go down into the asphalt and cause damage. So, cleaning a roof is a good idea, I just don’t want you to pressure wash it. There’s a chemical cleaning system that most local cleaners do, so I’d much rather you have a professional use a chemical cleaning system as opposed to a pressure washer. Now a lot of times they will use a pressure washer just as forced water. They’re using a tip on it, which doesn’t have a lot of pressure.  They’re keeping it back and minimum of 18 inches so that you’re not actually using enough force to actually force the granules off of the roof.

Ken: Yeah, it gets a lot of water on there and you have a good span, so I think 2 feet to 2-1/2 feet away after you’ve sprayed it with some bleach, with some trisodium phosphate and that sort of thing in it and let it sit on there for 30 minutes and then wash it off.

Kevin: Okay. Like I said, I’ve never – I’ve seen people roof cleaning the roof and all that stuff but it’s like “Why the hell do I want to wash the granules off for?”

Jared: You don’t. Cleaning it is a good idea, pressure washing not.

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