Quick question for the efficiency folks: in our 120k sq ft DC, switching Aisles 1–20 to a serpentine path cut average pick time per order by 14% across 2,300 ecom orders last month with no slotting changes. Is serpentine reliably faster for dense waves, or is this just a fast-mover placement fluke?
In our 90k DC, serpentine beat U-turn by about 11% whenever “lines per aisle entry” was >= 2.0; below that U-turn won, so we set a WMS rule to switch based on predicted lines/entry and made ends one-way to avoid head-ons. If your “dense waves” hit that threshold, it’s not a fluke — did endcap congestion drop?
Nice lift on the “14%,” @OP. One thing that made serpentine reliably faster for us in Aisles 1–24 was staggering picker starts (odd aisles go northbound, even southbound) so endcap queues don’t form; that added about 6% on dense waves beyond pathing alone. Small caveat: if your endcaps are under 8 ft clear, the gains vanish — what’s your endcap width in 1–20?
14% in Aisles 1–20 reads like fewer endcap pivots and less blocking, not a slotting fluke. Quick test: flip only the even aisles back for a week and track “feet per line” plus endcap dwell >8s in that 120k sq ft zone; if dwell jumps, serpentine is your default. With longer two-bay carts the edge widens, @riley_morgan85.
Feels like classic “mowing the lawn”: zigzag shines when the grass is thick, drags when it’s patchy. Building on @lucas879, add a WMS rule that breaks the zigzag via the nearest cross‑aisle whenever predicted max gap in a lane exceeds about 60 ft; did you capture max gap between picks or just averages?