Was My Modified Bitumen Roof Installed Properly?
LESLIE: Nancy in Arizona is on the line with a roofing question. How can we help you today?
NANCY: We just got a new roof put on our house and it’s a two-ply, peel-and-stick, modified bitumen roof?
TOM: OK. Yes.
NANCY: And the guys came in and laid the sheets down and then rolled a big, heavy, 100-pound roller over it to adhere the two sides.
TOM: Mm-hmm. Yep.
NANCY: But we earlier – what they took off our roof was a five-ply tar and – a five-ply roof.
NANCY: And I understand it was an industrial roof, almost, on our house.
TOM: Right, right. Yeah.
NANCY: And my husband and I are wondering if we’re looking at half of the roof that we used to have or if it’s a good one, because they keep bragging about the new technology and how good everything is. But we get up there and we look at it and we’re looking at this teeny, tiny, little, almost-immeasurable amount of roofing product on our roof and we’re just wondering.
TOM: Yeah. Yeah, well, it is kind of the lightweight version. Now, the reason you had to have five plies is because you needed five plies for it to be waterproof. I mean five-ply roof is five plies of tar paper with tar in between.
But a modified bitumen roof is a combination roof that actually has sort of a rubberized quality to it that makes it very, very durable and very UV-resistant. So you just don’t need to put multiple plies of that. You would never take that and put multiple layers; you would install it just the way you described.
So I think it was probably a good choice but of course, only time will tell. As long as the workmanship was done well, then you should have no worries about that.
NANCY: And that’s kind of under question at this point. But let me throw this in: they came back over because we were a little unhappy and they sprayed on two coats of that snow-roof kind of stuff on there?
TOM: Ah, I don’t …
NANCY: And they told us that it was going to help seal it and help bond it and help reflect the sun because as you might or might not know, it gets really hot here in Phoenix?
TOM: I’ve heard that. You know, I heard that. Yeah.
NANCY: And it’s a rumor but it’s true. And …
TOM: Did they put a – was it sort of like a gray-like, silver-like kind of …?
NANCY: Yes. It’s almost polar-white, actually, up there now. Blinding.
TOM: Yeah, yeah.
NANCY: And we’re really hoping that that hangs in, so …
TOM: Well, that – there used to be a product called fibrous aluminum that they would paint on roofs, that did the same thing. So those white coatings are not a bad idea as long as the coating is designed to work with the modified bitumen roof, as long as they’re comparable and compatible.
So what they did does not sound like it’s the wrong thing to do, as long as they use products that are designed to work together and secondly, again, as long as the workmanship was done well. That means that it’s sealed properly around the flashing where the pipes come through the roof, if you’ve got any types of curb walls or knee walls or anything like that. As long as that was installed correctly, those – all of those joints, that’s where the rubber hits the road. If that’s not really done well, when you do eventually get some rain there in Phoenix, Arizona, you’ll find out about it.
NANCY: Well, usually, when we get it, we get a lot of it. So, we’ll find out soon enough.
TOM: Yeah. You know what? You can always go up there with a hose and test it out.
NANCY: Well, we could. That’s a good idea. I hadn’t thought of that.
TOM: Yeah, give it a shot. Yeah, it’s not a very green thing to do but before the roofers get sort of too far out of mind, you could go up there and give it a shot.
NANCY: Right, right. Yeah, give it a try.
NANCY: Well, thanks. Thanks so much.
TOM: You’re welcome, Nancy. Good luck with that project. Thanks so much for calling us at 888-MONEY-PIT.