Lightning Protection Installation
A Lightning Protection System is comprised of several components: Air Terminals (Lightning Rods), Roof Conductors, Downlead Conductors, Ground Electrodes (Ground Rod, Ground Plate, Etc.) and Surge Suppression.
There are rules in the standards for each of these components. Air Terminals must be spaced a particular distance apart based on total length of the ridge or parapet wall. They must be a certain distance above what they are protecting and a certain distance from outside corners. They must be spaced so that no portion of the structure is outside of a zone of protection. Roof conductors must be sized according to the Class (I or II) of the structure and must be fastened 3'-0" on center maximum. Roof conductors may be installed either exposed on the roof or concealed below the roof. Downlead conductors may be installed concealed within wall construction, within conduit, or exposed. Exposed downlead conductors located at driveways or anywhere that it could become damaged must be protected up to 6'-0" above grade. Ground Electrodes must be installed minimum 2'-0" out from the foundation wall.