Unfortunately, no. The term metal is itself misleading because metal encompasses a plethora of different types of ferrous and non-ferrous alloys. The common type of metal roofing is actually a painted steel alloy with a galvanized base (dependent on the manufacturer it could also be a Galvalume base which is even more corrosion resistant). There is more than just steel in the metal roofing industry; Copper, Zinc, Aluminum and even raw steel are all options with some metal roofing systems.
To break it down a little more, steel roofing can be categorized into three groups. Two of these three groups can also be made from other alloys like Copper, Zinc and Aluminum, but we'll discuss that further on. The first group, common to large pole-buildings, is a direct fasten type panel known as the Ag-rib panel or Corrugated Steel. The second type of steel roofing is architectural steel shingles. These can also be made from different alloys. This style is typically made from a very thin, 29 gauge steel and stamped out at a factory and will interlock as it's installed, creating the traditional look of shingles with the lasting protection of steel (or other alloys). Finally we come to Standing Seam steel roofing (also capable of being produced from other alloys aside from steel). Typically, Standing Seam comes in 24 and 26 gauge steel, however a very thick and structurally sound 22 gauge can also be installed to truly create an iron-hide for the roof.
Now that we've broken down into the three major categories of metal roofing and the available alloys, let's dive a little further to weigh-out pro's and con's of each.
First we have standard direct fasten metal roofing, commonly known as Ag-rib and corrugated metal. This is a direct fasten panel intended to be installed as vertical siding and span over purlins on pole-buildings. Ag-rib was designed and intended for the pole-building industry to cost effectively provide a long lasting exterior. It is available in 24, 26 and 29 gauge steel, although 29 gauge is the most common. 29 gauge is thinner than the other two available gauges and often comes with a lesser quality paint system that's more prone to fading. Though the Ag-rib metal roof system is cost effective, it's major drawback is the overwhelming amount of screws that rely on a rubber gasket to prevent leaks. Also, being of such a thin gauge, it can be prone to tears from ice damns acting as glaciers moving down valleys on the roof. Overall, this metal roof system is great for simple roof designs and storage buildings.
Next up we have the metal shingle system. When installed correctly this thin gauge system can stand up to the challenge. But as we've discussed before, 29 gauge is lightweight compared to other options. This style tends to lean towards the more expensive side to install and it's performance on complex roof designs leaves much to be desired as snow and ice loads can cause immense amounts of damage acting like glaciers, if you're from Michigan you know the result of glacial movement. However, when looking for a traditional shingle look and the life span of a metal roof, Steel Shingles can stand up to the challenge.
Last, our personal favorite, we have Standing Seam. Standing Seam comes in both a snap-lock system that utilizes clips to fasten the panel to the roof and allows for thermal expansion and contraction of the metal and a Mechanically Seamed Rib which needs a special robot to form each panel to the next permanently. Standing Seam can be manufactured from coated steel, aluminum, copper, zinc and even raw steel to allow for a natural rust patina. With coated steel, Standing Seam can be manufactured from steel as thin as 26 gauge to as thick as 22 gauge! When Standing Seam is installed correctly it can provide the ultimate shield of protection for your home or business as well as a unique architectural styling. A few draw backs for some could be the move away from the traditional shingle look, the install process is significantly more involved than asphalt shingles and can take a considerable amount of time to complete a complex roof system and the price associated with complex roof designs. However, no matter the material chosen for the Standing Seam application, a properly installed system will have zero exposed fasteners and will last for years and years.