Metal Roofing… What We Think

Asphalt shingles are our most common shingle choice. Our second most commonly used material is metal roofing. We do a fair amount of it, but we only install standing seam (it’s also called covered fastener) metal. It looks like this:

But not all metal roofing is like this. You can also get metal roofing that goes on like this:

Notice that while it looks similar, the roof on the bottom has exposed fasteners. Those screws are grommeted to keep water from entering at the screw holes. Those grommets break down after about 18 years, and then there are pinpoint leaks all over the place, at every screw hole. The only thing that you can do is to either replace all the grommets or caulk the screws, and that’s very expensive unless you do it yourself. It’s cheaper to buy but costs a lot more to maintain over the long term. Corrugated agricultural metal is also much cheaper, but has the same problems long term.

The most attractive feature of a metal roof is its durability. Unlike shingle or composite roofing materials, properly-installed metal roofs are generally expected to last as long as the houses they protect. In fact, most metal roof warranties are for time periods of between twenty and fifty years.

Furthermore, the metal roofing material is constructed to better withstand a host of potential dangers. Obviously, it is resistant to fire; but its lack of porousness also enables a metal roof to shed moisture. This capability makes it impervious to rotting, mildew growth, and insect infestation – unlike shingle or wooden roofs.

We won’t install anything except the standing seam metal because we don’t have confidence in the other products, but we lose jobs to cheaper contractors because of it. It comes in many colors, even though all the examples are gray. What some people don’t realize is that the manufacturers don’t warranty the metal, they warranty the paint, usually for 25-30 years. That paint oxidizes after about 10 years and gets a weird white coating on it. If something damages the paint (falling branch, pine cones, pine needles) then the roof can begin to rust. Acorns will make visible dents on a metal roof, and you have to be really careful about where you put your feet. It does not grow moss or collect debris like asphalt does, and is easier to clean that asphalt. It is also very dangerous in the rain and snow (big slide).

There are also companies who can do different kinds of metal, like this: Interlock roofing roofs are not as great as they say they are, but they are beautiful, made of aluminum so they don’t rust, and are very expensive (a roof I’d bid for ten thousand will cost you thirty thousand with the Interlock roofing). You also can’t walk on it, no matter what they say. The other problem with them is that only the Interlock contractors can fix them if something goes wrong, and since the closest one is out of I think Beaverton you just gotta hope they’ll come when you need them. I saw one down the street getting replaced with asphalt a month ago – it was still intact and keeping water out, but the paint was coming off.

We hope this blog helped you learn more about metal roofing and the pros and cons of it. We stand behind our work and make sure that you get the best roof for your home. If you are in need of a new roof, give us a call and get a free estimate!