Repair a Roof Valley Leak
LESLIE: Ben in Illinois has a roofing question. What can we do for you?
BEN: Hey. I’ve got a situation over here I thought maybe you guys could help me with.
BEN: I bought a home about five years ago and it’s got a new roof on it and was real pleased with it. Well, last fall, the roof started leaking and when I looked at the roof to take a look at it, what had happened – whoever roofed it put new shingles on but they didn’t patch or – I guess they put some sort of metal or something in the valleys.
BEN: And the valleys are leaking real bad and I wondered if there’s some way to repair that without having to tear the whole roof off again.
TOM: (overlapping voices) Yeah. So, the valleys – which is where the two planes of the roof come together in the V-like shape, for those that have no clue as to what we’re talking about – these valleys have – are lined with metal flashing?
BEN: They’re – I don’t believe so, Tom.
LESLIE: (overlapping voices) I think they are not flashed.
BEN: I got up. It looks to me like it’s just tar paper.
TOM: Alright. So then, mmm. Well …
LESLIE: There’s no flashing, there’s no membrane, nothing.
TOM: (overlapping voices) Yeah. It’s not tar paper; I know exactly what you’re looking at, OK? I’ve seen – I’ve not been on your roof but I’ve seen many, many roofs that look just like this. What happens is it is a very heavy roofing material; it’s like a roll roofing material that is used to create this valley. And if they put a second layer of shingles on – they brought it up the valley but they didn’t replace the valley – it’s probably leaking and cracking and split.
And you can tar it but it’s a real stop-gap, Band-Aid-like measure. The right thing to do here is to pull a valley – basically, pull a valley apart and rebuild it. I mean, there’s no easy way to do this because you’ve got to start with the valley and put the shingles on top of that. But a good roofer can sort of almost disassemble the shingles and take it apart at the valley and then rebuild that one piece of it. Or perhaps, you may be able to work some copper flashing under that, on both sides, without taking the whole thing apart.
Now, the key here is if you go with a metal flashing, a mistake most roofers make is they use one continuous piece. Huge mistake because it expands and contracts like crazy and you’ll get stress fractures. If you use sections that are like three or four feet long and stack them up one on top of the next, it’ll last a long time; you’ll get 20 years out of it.
But it’s definitely a roof repair that has to be done. You could, you know, tar it for a temporary fix but it might get you through a season. But at some point, you’re going to have to bite the bullet here and tear that valley apart and rebuild it the way it’s supposed to be.
BEN: Right. OK. Well, Tom, I always – I will listen to your show every week. I always appreciate your advice. Thank you, sir.
TOM: You’re very welcome, Ben. Thanks so much for calling us at 1-888-MONEY-PIT. Happy to help you out.