For a long time, your main option for roofing materials was asphalt shingles. Few other choices were available, and if you wanted a different roofing material, you had better be prepared to pay top dollar for it.
Standing seam metal roofs were only a figment of the imagination in the minds of average homeowners. Most metal roofs were confined to commercial buildings or only to very cool, very expensive architect-driven residential structures. Now, they seem to be popping up on every block. Will standing seam metal roofs supplant composition shingles as the roofing material of choice?
Composition Shingles vs. Standing Seam Roofing
Asphalt and composition shingles do have their high points, and they are not going away anytime soon. For one, if you want to purchase a dead-cheap roofing material, asphalt and composition tend to be the way to go. There are two problems with composition shingles, though. First, the cost of composition shingles is influenced by oil prices, as they are derived from petroleum. This means that prices can fluctuate due to pressures outside of the roofing industry. Second, composition and asphalt shingles tend to lose surface material.
If you have ever cleaned out your gutters (assuming you have asphalt shingles), you know quite well how these shingles have a propensity to slough off the upper mineral-based surface. After enough seasons, conventional shingles have literally been worn down to the core. Sweeping the shingles or, worse, power washing them will only speed up the process.
Standing seam metal roofs are a completely different product. Not only is the type of material independent of petroleum prices, but the size and shape of the material and its installation methods are different, too. Many homeowners find that the higher initial cost of this type of roofing will pay off in the end because of its greater durability and reliability.
What Standing Seam Means for Roofing
Standing seam metal roofing is a particular type of metal roofing that raises the seams above the level of the roofing itself.
Houses in your neighborhood with metal roofs most likely are of the standing seam variety. Continuous panels run from the ridge of the roof all the way down to the eaves. Between the panels are seams connected by fasteners which are raised above the level of the metal roofing.
This is where we derive the term standing seam, because the seam is raised, or standing, as opposed to flush-mounted. Because seams are always the weak point with any kind of building material, especially roofing, raising the seams above water level is a key advantage.
Elements of Standing Seam Roofs
- Seam Fasteners: These seam fasteners might be anywhere from 0.5 inches to 1.5 inches high. Because these fasteners are concealed, you only see a smooth continuous ridge extending from top to bottom.
- Pre-formed vs. Site-formed: Roof panels can come either pre-formed or site-formed. Pre-formed panels are created in an off-site factory. Site-formed panels are created from rolls of metal that are run through mobile forming machines that crimp the metal into rigid panels.
- Composition and Width of Panels: Panels tend to run 12 to 19 inches wide. Panels are usually made either of Galvalume-coated steel or aluminum.
- High Seams: One great advantage of standing seam metal roofs is contained in the name itself: seams, the weak point in any roof and a potential entry point for moisture, are raised above the level of the roofing panel. This cannot be said for composition shingles or especially for torch-down or rolled roofing.
- Fewer Seams: Because the metal panels run unhindered from the top to the bottom of the roof, not only are there no horizontal seams but in total the roof has far fewer seams.
- Durable: Metal is tough and durable, but it's not impervious to all hazards. The sheet metal in this type of roofing can be penetrated by heavy falling limbs or dented by a severe hailstorm.
- Long-Lasting: With proper maintenance, you can expect your metal roof to last between 30 and 50 years.
- "Cool Roof": All metal roofing, in general, is considered a "cool roof" by the US Environmental Protection Agency. This is because metal roofing can be painted any color, including colors on the lighter end of the spectrum which will prevent solar heat gain. Composition shingles are difficult to paint.
- Sleek Looks: Standing seam roofs are perfect for certain types of contemporary or country-style houses. Due to the smooth, straight lines, these roofs give your house an industrial feeling -- yet with a modern flair. These are not the rippled tin roofs that you might remember from warehouses of the past.
- Multiple Colors: Metal roofing comes in a decent array of colors: grays, browns, forest greens, earthy reds. While this is not the full palette of colors you might find at a paint store, it is far more than you will find with composition/asphalt shingles.
- Fewer Roofers: Nearly every roofing company in your area can install composition or asphalt roofing shingles. But far fewer contractors install metal roofing, and fewer still install them well. This means that you will be searching longer for a good roofer, and the total project cost may be higher because competition in the market is lessened.
- Unsuitable for Flat Roofs: Roof pitch refers to the angle of the roof's slope. Certain types of metal roofs do not lend themselves well to flatter (or completely flat) pitches. Snap-lock panel metal roofs are not advisable for roofs with a pitch of 2:12 or less (2 feet of vertical rise for every 12 feet of horizontal rise). However, with a better quality mechanically-seamed panel, it is safer to go to a 1/2:12 pitch. You can even bump the seams up to 2 inches with a butyl seal for those applications. It is important to note, too, that when you get to these lower pitches, you are below the recommended minimum pitch even for conventional shingles. Generally, these safely go down to a 4:12 pitch, with some shingle manufacturers warranting their product down to 2:12.
- Cost: Metal is considered a moderately expensive roofing material, more expensive than conventional shingles but less than high-end slate or copper. However, metal's higher cost can be amortized via its longer lifespan.
- Not a Panacea: While metal itself is fireproof, many factors contribute to make a house a fire hazard. Some homeowners may be lulled into a false sense of safety with their metal roofing, believing it will render their home completely safe from all fires.