Warehouse Overhead Door Projects High Lift Doors for a Container Depot China Project reference: High Lift Doors for a Container Depot. Customer Challenge A container depot needed doors clearing double-stack reach stackers at the dock line, with only 4.5 m of headroom available. Our Solution We installed high lift sectional doors with low headroom tracks, heavy duty springs and traffic signal integration. Results Reach stackers pass through with full margin and the spring systems remain within specification after two years of double-shift use.