An elevator with two stacked car compartments sharing a single hoistway and drive system, simultaneously serving two adjacent floors to nearly double the passenger throughput of a single-deck installation.
Full Definition
A double-deck elevator consists of an upper deck and a lower deck rigidly joined in a single car frame, travelling together on one set of guide rails driven by one machine. At each stop, the upper deck aligns with one floor while the lower deck aligns with the floor below (or above, in some configurations). Passengers pre-select their destination floor to determine which deck they board — destination dispatch systems are therefore integral to double-deck operation. The principal advantage is that traffic handling capacity approaches that of two independent elevators in the same hoistway footprint, making the solution attractive in high-rise buildings where core space is at a premium. Challenges include: the inter-deck distance must match the floor-to-floor height; an adjustable inter-deck mechanism (e.g. scissor mechanism) can accommodate varying floor heights. Total car weight and structural loads are significantly higher. Counterweight and machine are sized for the combined mass.
