Two crossover bridges over a live conveyor line.

The brief

A long sortation conveyor ran east-west across the warehouse, dividing receive operations on the north side from ship-out operations on the south. Walking around added significant time per trip; the operator reported notable productivity loss from the cross-floor detour. They wanted two crossover bridges so workers could go up-over-down at two locations, leaving the conveyor uninterrupted.

Constraint: the conveyor couldn't be modified, couldn't be temporarily relocated, and couldn't have material stockpiled around it during install. The crossovers had to install over the conveyor without disturbing it. Production ran on a near-continuous schedule except for planned shutdowns; a holiday window was the only feasible install slot.

What we built

• Number2 crossover bridges
• Span24 ft each (column-to-column)
• Bridge deck width1100 mm (foot-traffic clear)
• Total rise10 ft (5 ft up to clear conveyor + 5 ft down)
• Stair configSwitchback up + switchback down at each end (4 stair flights per crossover)
• Live load4.8 kPa + 1.3 kN concentrated
• DeckBar-grate (no spill to conveyor; sprinkler reach preserved)
• Guard42" pipe rail with kick-plate (full crossover perimeter)
• Anchor schemeBolted to existing W14 building columns; no slab penetrations
• FinishShop primer (interior, dry environment)

The anchor question

Anchoring a crossover bridge requires somewhere to land the load. Two options were on the table:

• Floor-mounted columns — separate columns flanking the conveyor on either side. Cleanest structurally but takes floor space adjacent to the conveyor that the operator wanted clear.
• Existing building column attachment — bracket-mount the crossover ends to existing W14 building columns. Saves floor space; depends on the building columns having capacity.

We pulled column drawings from the building owner; documentation was complete enough to confirm capacity. Existing columns showed adequate capacity for the crossover load with margin. Connection design was a bolted bracket with through-bolts in the column web — no welding to existing structure (minimizes shop / hot-work permits).

Pre-fabrication and the install plan

Both crossovers were fabricated in subassemblies that fit through the building's loading-dock doors. Each bridge broke into:

• 2 stair flights (one each side, switchback)
• 2 mid-landings
• 1 bridge deck (24 ft, three-piece for transport, bolted at install)
• 4 column attachment brackets (factory-pre-assembled to columns at site)

Install plan: 2 days per crossover. Day 1 — column brackets, stair flights, landings. Day 2 — bridge deck, guard rail, sign-off walk. Conveyor never moved; piece sequencing meant no piece passed within 4 ft of the conveyor at lift point.

Install — 4-day holiday window, both crossovers

• Day 1 (afternoon): shutdown begins; staging — both bridges' material delivered, lay-down established, lift positioned.
• Day 2: statutory holiday — no work.
• Day 3: Crossover 1 install — column brackets, stairs, landings, bridge deck.
• Day 4: Crossover 2 install (same sequence) + guard infill on both + final cleanup.
• Restart morning: facility manager sign-off walk; conveyor restart on schedule.

Outcomes

• Both crossovers operational on schedule; conveyor restart unaffected.
• Operator reported significant pedestrian-time recovery across the operation as cross-floor travel stopped routing around the conveyor.
• No post-install structural callbacks at follow-up inspection.

Client testimonial and quantified time-savings pending publication approval.