The metal roof is the ideal host for mounting solar photovoltaics (PV) as it is the only roof type with a service life that exceeds the service life of a solar PV system. Most alternative roofing systems will expire long before the life of the PV system, leading to costly disassembly of the solar array, re-roofing and re-assembly.
Mounting Solar PV on Metal Roofing
Conventional rails have traditionally been the choice for attaching solar modules to all roof types. But familiar concepts don’t necessarily deliver the best outcomes, and the advantages of rail-less, direct-attach solar mounting to metal roofs are moving the industry norm in a new direction.
Reduces Costs
Rail-less solutions leverage a metal roof’s existing construction allowing the standing seams of the roof to be utilized as inherent (and cost-free) “rails” for mounting solar PV via reliable mechanical attachments, thereby eliminating the need for a traditional rail system.
Rail-less components are much lighter than railed systems and direct attachment of solar modules to a metal roof can be accomplished with fewer components and lightweight materials. So, the weight of mounting components is reduced by up to 85% and the cost of hard goods by up to 35%.
Because every clamping point on a PV module attaches directly to the roof, rail-less racking results in a 25% better load distribution across the roof and zero penetrations, which preserves both the integrity of the roof and the manufacturer’s warranty.
Simplifies Logistics
Rail-less makes shipping, storage and transport simple and much less expensive. Shipping long lengths of rail to a project site, storing and transporting them up to a rooftop is costly and frequently a logistical nightmare.
Since rail-less solar mounting systems are 15% the weight and 90% less volume than rail-based solar racking, shipping costs can be 60% lower than rail-based systems, with fewer logistical hassles. With rail-less, off-site storage is seldom needed, and costly cranes and forklifts to move racking hardware to the site and up to the roof are often eliminated.
Eases Installation
With fewer components than traditional systems, rail-less solutions make it simple and easy to get all the components into place, which is especially beneficial when working on a steep slope. Installers can easily mount around obstacles, removing the awkward field-cutting of rails. Plus, impromptu changes in module layout are possible if needed.
Labor Savings
The key to labor savings (30 to 50%) is twofold: the elimination of time traditionally needed to measure, locate, and install rails, and the simplicity of rail-less attachment: requiring 65-75% fewer components to manage and install. Rail-less is designed so roof clamps can be quickly aligned and installed to modules “on-the-fly” without needing to measure or snap lines, using the module as a spacing jig to locate and install attachments.
Protects the Investment
The value of metal roofing lies in its durability–in most cases lasting up to 70 years. Any roofing attachment needs to ensure that this durability and long-life cycle remain intact. The low profile offered by a rail-less system provides an aesthetically pleasing appearance with its sleek visual appeal and safeguards the array’s performance and roof integrity.
Rob Haddock is the CEO and founder of Colorado Springs, Colo.-based S-5! Together with his sons, they co-invented the PVKIT rail-less direct-attach solar solution, providing a simple, secure method to “lay & play” PV modules with tested, engineered, cost-saving, attachment. To learn more, visit www.S-5.com.