Correctly installed metal tiles and shingles provide durability and minimal maintenance
Growing in usage compared to traditional asphalt roofing, metal tile/shingle roofing offers durability, fire and fungus resistance, and low weight among its many benefits. Metal tile/shingle roofing has a recycled content as high as 95 percent. It won’t ignite, rot, warp, break or chip. Since water run-off from most metal products is not harmful to groundwater, this aids water conservation. With its ability to withstand high winds and the elements, metal tile/ shingle roofing can become a permanent part of a building-protecting and beautifying it for years. Metal tile/shingle roofing can be installed over existing materials, diverting them from a landfill. However, its “difficult and costly” installation reputation has kept metal tiles and shingles from being used more frequently. It has been misperceived as requiring special tools and extensive training. But modern metal tile/shingle installation is debunking this myth, and becoming easier and faster to install with lasting results.
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Metal tile/shingle pre-installation
Before metal tile/shingle installation can take place, the overall condition of the roof should be assessed. “If the project is new construction, the roof deck should be inspected to determine if a level plain has been installed,” says David Smith, technical services manager, ATAS International Inc., Allentown, Pa. “For a re-roof, the existing deck and roofing materials should be closely inspected to determine if the surface is adequate to receive the new panels or if deck repairs should be performed. Interior attic space areas should be part of this review. In either case, the new or existing deck should be checked for squareness. Local building codes should be reviewed to determine if existing roof materials on re-roof applications can remain or must be removed.”
In areas prone to hurricanes and high winds, installation must meet local standards and codes. ATAS’s VP of sales and marketing, James Bush, states metal tile/shingle may need appropriate underlayment materials. “Appropriate roofing underlayments should be applied to the roof using the manufacturer’s installation recommendations,” he says. “Once the roof is ‘dried in,’ low-side flashings should be installed. These include eaves and valleys. Installation of the metal tile/shingles is then performed.”
Metal tile and shingle products can be installed on many different roof shapes. Most systems are, however, confined to use on roof slopes of 3:12 or greater. Most metal tile/shingle systems can be used on commercial and residential applications, but again, local codes may vary depending on the type of building. Also, “There may be some differences in deck assemblies the panels will be applied to,” Bush says. “Fastener selection and/ or attachment methods should be modified to suit the assembly.”
The installation
While specific metal tile/shingle installation may vary, usually it comes down to installing a system of interlocking modular panels. These interlocks hold them tight in high winds and also allow all of the fasteners for the roof to be concealed. Special details are available for specific metal tile/shingle installations; not all metal tiles/shingles are the same. Some only lock together on the top and bottom, instead of on all four sides. Some don’t even lock together top and bottom, but instead have exposed fasteners driven into battens beneath the roof. Many metal tile/shingles are installed horizontally in a left-to-right pattern and staggered from eave to ridge-fastened to a solid substrate through pre-punched nailing holes.
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“Metal tiles and shingles can be installed direct to the deck, or on a batten system,” says Meredith England, market specialist,
DECRA Roofing Systems Inc., Corona, Calif. “The deck can be plywood or metal; same is true for the battens.” Regardless of installation differences, this installation process demands careful consideration and detail. For instance, it is important to consider water flow and overlap materials in the correct sequence.
According to Louis Rondeau, national applications training manager at RHEINZINK America Inc., Woburn, Mass., “Each project is different, so step-by-step procedures for installing tiles are going to vary from structure to structure- commercial or residential, and roof to façade.”
Rondeau offers a list of things that will be static from project to project:
• Review the drawings and the specification. Depending on the metal called out make sure that the roof pitch is conducive to the material being used.
• Take field measurements.
• Create a materials list (or cut sheet).
• Determine the labor that’s needed.
• Order materials.
• Define the logistics.
• Determine who will be fabricating the tiles or shingles-noting that some fabrication may only be done at the site.
• Most metal manufacturers have basic guidelines for their material or products that provide the end-user with an understanding of the attachments required and watershedding requirements. The tools used depend on the installation method.
“Batten products require a guillotine/cutter and a ridge bender,” England says. “Direct-todeck products have no special tool requirements and utilize the ‘Cut & Tuck’ installation method in which the panels are cut and fitted into channel pieces. Panels are easily cut with a circular saw or on a table saw.” Rondeau states that depending on the complexity and size of the metal panel/shingle installation project, standard hand tools are typically utilized, such as:
• Snips and hand benders: used in field-fabrication
• Hammers and clamps: used in installation
• Levels, lines and wedge bars: used to provide uniformity
• Drills: for panel fastening
One way metal shingle/tile installation has become simpler is by moving away from products requiring a batten system for installation, to products specifically designed for easier direct-to-deck installation.
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“With changes in machine tooling, DECRA has introduced four profiles that have a hidden fastener system,” says England. “The nose of each panel slides onto the clip that is formed at the top back edge of each panel in the row below. The fastener is then put into the pre-drilled holes in the back shelf which is covered when the next subsequent course is installed.”
During installation, follow safe roofing practices, wear appropriate clothing and use safety equipment. Fall protection methods must be used; metal shingles/tiles may be slippery. Light softsoled shoes are recommended. Walk only on the top portion of the metal shingles/tiles and avoid walking on the locks/seams.
After metal tile/shingle installation, topside flashings and closure components can be applied to finish the job. “Flashing details are often very different for metal tile/shingles than those associated with traditional vertical seam roof panels,” says Bush. Be sure to clean all debris off of the roof after installation, especially any metal shavings. If a panel or shingle needs to be touched up or repaired, touch-up kits are available in matching colors to do so.
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Easing metal tile/shingle installation
Every job is unique and we like to work closely with installers and even property owners to discuss any unique things about the job at hand and arrive at solutions that will work. We have often designed and made custom flashings. We can also do drawings, mock-ups and videos which we send to installers to show them how to handle special areas. Things like flared gables and dead valleys can be very tricky and the standard parts that most manufacturers provide will not work. These are just two areas which require custom flashings. We also like to look at roofs and consider how water will flow on them, as well as where debris such as tree leaves, pine needles, ice and snow may collect. A long-term successful roof installation will consider all of these things. We do offer free installation training at our location in Ohio and we can provide job-site training for a small fee. We also know many experienced installers and can often connect new companies with them for training or even sub-contract installation.
Todd Miller, president, Isaiah Industries Inc., Piqua, Ohio
