Remove Moss From a Slate Roof
Alright, calling in from my neck of the woods – Long Island, New York – we’ve got John who has a roofing question. What can we do for you?
JOHN: Yeah, hi. I have and old house and I have a slate roof on it.
JOHN: On the north side, it’s got a loss of moss. Is that OK or should I remove it?
TOM: No, it’s not necessarily a problem. What can you do about it? Well, a couple of things. First of all, if you want to remove it, you need to wash it down with a mildicide and there are a number of different products out there that you can do that with; like OxiClean, for example. You want to apply it, let it sit and then you can rinse it off until it goes away.
If you want to prevent it from coming back, you can add a copper strip to the ridge or a nickel strip to the ridge and when the rain hits it it’ll run down the slate roof and acts as a mildicide and cleans that. And the third thing that you can do is look to whatever is causing the shade on that side of the house – if you have any high trees overhead or anything like that; try to let a little more sunlight on that side and that will stop it from growing back as well.
But it’s not hurting anything and as long as you don’t mind the look of it it’s not going to cause leaks. You can just live with it.
JOHN: OK, so it doesn’t get under the slate (inaudible at 0:05:23.1) tiles.
TOM: (overlapping voices) No, rarely, rarely. Yep, it can get pretty thick but it rarely causes a problem; especially with slate. With asphalt roof shingles, it can break a shingle now and again but it’s not something to panic over. OK?
JOHN: That’s great. Thanks so much.
TOM: You’re welcome. Good luck with that project. Thanks so much for calling us at 1-888-MONEY-PIT.