As a metal roofing contractor, I get a lot of questions about different metal roofing systems and whether or not they would work in certain situations, of which the most mentioned problem is preventing Ice Dams. Also, here in southern New England (Massachusetts, Rhode Island and Connecticut)  we have a very unique situation with metal roofs. On one side, metal roofing is not very wide spread here and therefore most people are unaware of these excellent and permanent roofs. However, because of our close proximity to NH, ME and VT, many homeowners who consider a longer lasting roof than asphalt shingles, usually mention a metal roof that they’ve seen “driving through NH”.

Because of such situation, most people that are aware of metal roofing, think that New Hampshire style vertical panels (standing seam roofing) are the only metal roofs in existence, or are the best because that is what they’ve seen.

Despite popular belief about standing seam being “the only” or “the best” metal roofing system, this is just not true. I will mention that though that standing seam metal roofs are very good, and time proven systems, but they have a few negative aspects to them, which make them “not the best” for me personally. You can read my complete overview of why standing seam is an inferior metal roofing system at the end of this article.

Comparing different metal roofing systems:

Getting back to people’s general knowledge about metal roofing – there are many other metal roof systems out there, which in some or most aspects are just a good or better than standing seam roofs. In this article I will try to introduce you to other metal roofing systems, and compare the on the basis of product quality, system design, ease of installation, and price. Just to let you know, ease of installation and price are very inter-dependent, thus the more difficult it is to install a roofing system, the more you will have to pay for it.

So without further adieu, the me introduce our main contender (first one is standing seam, against which I will compare other metal roofs) -Interlocking Shingles. I will omit talking about other systems such as Metal Shakes because they are very similar to metal shingles, and stone coated steel roofs, because besides good looks, while the do work – they are pretty horribly designed (my personal opinion as an installer).

Steel and aluminum interlocking shingles:

Interlocking metal shingle are just that – they have locks or hooks on all four sides. These locks hold the shingles together, preventing water and ice form penetrating the roof, while clips and nails hold the roof down to the deck. Interlocking metal shingle roof is the most versatile metal roof that exists. It can adjust to any normal roof penetration. It is easily installed on hips, valleys, side and end walls. Flashing a skylight or a chimney with metal shingles system is a breeze, if not pleasure (Read the last section of this article, about flashing skylights with standing seam roof panels).

Metal shingle systems that I know of, are VERY well designed. Very durable 3/4″ locks on all sides, easy install sidewall and gable flashing, T-valleys, all with built-in water run-off channels make installation of metal shingle roofs fast, and overall roof quality – outstanding.

Metal shingles installation:

The pros & cons of Standing Seam roofing:

First, the good: In many situations standing seam will be an excellent system that will last for decades, protecting your home or business from rain, snow, high winds, ice dams, etc. If your roof is simple gable, you can also expect a relatively reasonable price for your roof. If you have a walkable roof, the price may decrease a bit more.

The bad: If your roof gets complicated, you can expect to pay a lot for a standing seam roof, and even more for very steep roofs. The main reason for this is the way that a standing seam roof is designed and installed. Because of the vertical panel design, there is no way to put up any kind of roof brackets, so moving on such roof becomes extremely difficult and dangerous. While on a steep gable roof an installer can use a special hook ladder, thrown over the ridge, and move it left or right and he needs, working in valleys or even worse, on hip roofs, borders impossible, without a boom lift, except for roofs with low slope (3-4 in 12).

Another major limitation of standing seam roofing is the inherited design flaws. The ribs on the panels make it a very difficult system to install, when it comes to any kind of flashing detail. For example it it is a wall flashing, the panel must be cut, making sure the cut is straight. Then a lip has to be bent up, and only then the panel can be attached to the roof. But this is not all. Now it is time for Z-bar to be installed and ofter than a side-wall or head-wall flashing. Mind you all of this must be done while installer is on the roof, with all kinds of tools, and trying not to fall off the roof.

While all of the above is doable, and is done on regular basis, there is on type of flashing detail for which there isn’t a single good way to do it. I’m talking about chimneys and sky-lights. There are different ways to flash them, but all are reliant on caulking to make the watertight. The problem in in the back pan of every sky-light of chimney flashing (unless chimney has a cricket) and connection between back-pan and z-bar/sidewall flashing on the sides of the sky-light or a chimney.

I’ve included a link to one of the “best” ways to install such flashing detail, which for one, is very complicated, and I still would not use it. The problem is that there is no better way. Please review the sky-light / chimney flashing detail produced by ATAS. You may also read this thread on ContractorTalk regarding skylights in standing seam: http://www.contractortalk.com/f15/skylight-metal-roofing-60324/

So in a nutshell, standing seam is great when you have an easy roof. As soon as your roof gets complicated, you want to stay away from standing seam. If you still choose to use it, expect of of the following: A contractor you hire (I just don’t see a home owner installing a complicated standing seam roof) will charge a lot for a good installation. If you get a “deal”, expect a frustrated contractor cutting every possible corner. If you hire an eager contractor, chances are it the their first complicated standing seam metal roof and you will get mediocre quality at best, if the contractor actually manages to finish the roof. Some just stop in the middle of installation and never come back to it, leaving you with a roof half-done.

Corrugated steel vs. standing seam roofing:

Many people confuse standing seam with corrugated steel roof. Former one is an all concealed fasteners system, while the latter is an all exposed fasteners system. Also, corrugated steel roofs are made of cheap thin gauge (29 GA usually) steel painted with acrylic paint instead of 24 or 26 GA Galvalume or G-90 galvanized steel painted with Kynar 500 baked on coating consisting of 7 total layers of primer and paint. Kynar is actually a de-facto  industry standard, when it comes to metal roof paints. Corrugated roofs are those that you can often see with rust spots all over and have a short life expectancy with high potential for leaks

Conclusion

Basically, unless you are absolutely in love with the looks of standing seam roofs, I strongly recommend getting an interlocking shingles metal roof – be it steel or aluminum. Price wise, you will get same (if not better) performance at about 40% less money. You will also have a happy contractor, which is important for you in the first place, especially if your roof is more or less complicated. You contractor won’t hate life while working on your roof and you will get a better installation quality (which is the most important part). In one sentence – you get a better product for less money – can’t beat that!