Splice bars are used to join together lengths of SolarMount Rail or SunFrame. Splice plates are also structural and may be used only with SolarMount Standard Rail. Expansion joints allow for thermal expansion and may be necessary when rails exceed 30 feet. Only splice bars may be used for thermal expansion joint. To create an expansion joint, slide the splice bar into the footing slots of both rail lengths. Leave a half inch between the segments. Secure the splice bar with two screws on one side only. Footings (such as L-feet or standoffs) should be secured normally on both sides of the splice. No PV module should straddle the expansion joint.