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Roof Shingle Discoloration Could Be Mildew

  • Transcript

    LESLIE: Don in Virginia listens on WFHG and you’ve got something going on with the shingles at your house. Are you talking roof or are you talking siding?

    DON: I’m talking shingles; the roof.

    LESLIE: OK. How old is the roof currently on your house?

    DON: Probably about 15 years.

    LESLIE: And what are they made out of?

    DON: Asphalt.

    LESLIE: OK. Do you know is there one existing layer of shingles on your roof? Or is it several layers built on top of one another?

    DON: Well, it’s one layer with tar paper underneath. And they’re beginning to show discoloration different places. And also, there are some little particles in the gutter.

    TOM: Well, a little bit of discoloration’s not a bad thing. And 15 years old …

    LESLIE: That could just be mold or mildew growth.

    TOM: Yeah, or moss growth. Sure. And in some of the – having the granules in the gutter; also not unusual. Do you have any other indication that the shingles are bad, Don? Are they curling or are they cracking or anything like that?

    DON: No, sir. They’re not cracking or curling either. It’s just the discoloration. And I notice it’s on the side of the house with the least sun.

    TOM: Well, ah, there you go.

    LESLIE: (overlapping voices) Well then that’s definitely moss or mildew or …

    TOM: Yep.

    LESLIE: … something along those lines. Generally, that grows in areas where you get a lot of moisture and then you don’t get a lot of sunshine to dry it out. So, it could be that it’s the north side of the house or it’s under a big tree. Generally, what you want to do with that is if you feel comfortable getting up on your roof, you want to clean it with either a homemade remedy of bleach and water – put it on there; usually it’s like 20 percent bleach, 80 percent water, 30 percent bleach. You know, depending on how, you know, much you want to do. And really get it on there. Let it sit. Try to do it on a sunny day if you can. Trim back any tree that’s, you know, hindering sunlight on the roof. Let it sit there. Give it a good scrub with, you know, a stiff brush. But don’t be too aggressive because you don’t want to damage the shingle. And then that should do the trick.

    Otherwise, Tom likes a product called Jomax, which is also a cleanser. And if you can get sunlight to that area, you should be able to clean it.

    DON: Well, I thank you very much. And I do have a tree nearby and I suppose that could be part of the problem.

    TOM: You know, Don, if you cut back a little bit of that tree and just try to get a little more sunlight on that roof, you’ll find that it won’t build up nearly as much. And after you get it clean, there’s one more trick of the trade. And that is you could add a copper or a nickel ridge vent to that roof and as the rain water washes against that, it’ll release some of its metal and that will have a cleaning effect as well.

    DON: Well, I certainly do appreciate the information.

    TOM: Don, thanks so much for calling us at 888-MONEY-PIT. 

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