Racking System
The mounting hardware that secures solar panels to your roof — a critical structural component that must penetrate roofing material and attach to rafters.
Solar racking (or mounting) systems secure panels to the roof structure and determine tilt angle and orientation. For pitched roofs, flush-mount systems position panels parallel to the roof surface (typically 2–4 inches above to allow airflow that keeps panels cooler and more efficient). Flush mounts are aesthetically preferred but cannot optimize panel angle.
Proper racking installation requires penetrating the roofing material and attaching lag bolts to rafters or roof trusses — structural members, not just sheathing. Each penetration is waterproofed with flashing. Improper penetrations are the leading cause of solar-related roof leaks. Quality installers locate every rafter with stud finders and confirm load-bearing capacity before drilling.
The IronRidge, Unirac, and Quick Mount PV systems dominate the residential market. All-black mounting systems (matching black panels and frames) are available for HOA-sensitive neighborhoods at modest premium. For flat or low-slope roofs, ballasted systems (weighted without roof penetrations) are common on commercial buildings; residential flat roofs can use tilted racking to optimize panel angle.
Real-World Example
The installer located all 22 rafters before drilling; two of the initial proposed attachment points landed on sheathing rather than rafters — they adjusted the layout rather than drilling into non-structural material, avoiding potential structural and waterproofing issues.