Pallet Racking at Bethlehem Commerce Center and the Valley's Brownfield Conversions

Bethlehem Commerce Center occupies roughly 1,600 acres of the former Bethlehem Steel plant land on the city's south side, with Keystone Opportunity Zone designations on parts of the site. It is the single largest industrial redevelopment story in the Lehigh Valley, and it produced something unusual: two completely different kinds of warehouse sitting on the same ground. Brand-new Class A fulfillment boxes at 36-to-40-foot clear stand within sight of converted heavy-industrial buildings that were pouring steel when Eisenhower was president. A rack system designed for one will underperform badly in the other. This guide covers what changes when you rack a building that used to be something else.

Why Brownfield Racking Is Different

Racking a purpose-built distribution center is largely a math problem: measure the cube, model the SKU velocity, pick a density system. Racking a converted industrial building is an investigation. Four things differ, and each one can stop a schedule if it surfaces during install rather than during design.

The slab is an unknown. Purpose-built warehouse slabs are documented, consistent, and poured to carry rack base plates. A Steel-era slab was poured to carry machine tools, furnaces, and rail — which means it may be extraordinarily thick in one bay and thin in the next, reinforced in ways nobody recorded, or sitting over buried footings and utility trenches from equipment removed decades ago.

The structural grid is irregular. Modern spec buildings use consistent column spacing chosen to suit rack bays. Heavy manufacturing buildings used column spacing chosen to suit production lines and crane runs, which rarely divides evenly into 8-foot or 12-foot rack bays. Laying rack out on the theoretical grid rather than the real one produces drawings that do not fit the building.

Legacy obstructions are everywhere. Crane rails at height, filled or open pits, floor trenches, embedded rail sidings, and equipment foundations left in place after demolition all constrain where rack can physically go and how high it can run.

Clear height varies within one building. A converted mill can run 30 feet under the high bay and 18 feet under an adjacent low-bay section, with a crane rail cutting through the usable envelope in between. Single-height upright schedules do not survive contact with these buildings.

The Slab Problem: Core It, Do Not Assume It

Anchoring rack to an unverified slab is the most common serious mistake in brownfield work. Base plate punch-through, anchor pull-out, and failed inspections all trace back to the same root cause: someone assumed a slab thickness instead of confirming it.

The standard workflow on any Valley conversion is:

• Core in multiple locations, not one. A single core reading is a data point, not a slab profile. Thickness in a Steel-era building genuinely does vary across a floor plate, and the thin spot is what governs your anchor design.
• Check for buried structure. Old equipment foundations, footings, and utility trenches sit under floors that look uniform from above. These are as much a problem as thin concrete — anchoring into a void or a buried duct bank fails differently but fails the same.
• Verify subgrade quality. Concrete thickness alone does not establish capacity. What sits under the slab matters, especially on filled ground, which is common on redeveloped industrial sites.
• Engineer a remedy where the pour cannot carry the load. Where the existing slab will not support the base plate load, the answer is a footing detail or a slab-repair pad engineered into the package, not a larger anchor and optimism.

This work is slower up front than racking a spec building. It is also what prevents the field changes that blow up install schedules, and it is far cheaper than remediating a failure after the system is loaded.

Designing Around Crane Rails, Pits, and Rail Sidings

Heavy-industrial conversions come with permanent features that are expensive or impossible to remove. The design approach is to treat them as fixed and lay the system out around them.

Crane rails constrain vertical envelope, not just floor space. Where an overhead crane is still in service, rack height has to clear the load hook at its lowest travel plus a safety margin, and the crane's travel path cannot be blocked. Where the crane is decommissioned but the rails remain, the rails themselves still occupy the envelope.

Filled pits and trenches are the ones that surface late. A pit backfilled without engineered compaction will not carry a rack base plate, even when the surface concrete looks continuous with the rest of the floor. These need to be identified during the survey and either avoided in the layout or remediated.

Embedded rail sidings running through the floor plate constrain both anchor placement and lift-truck travel. Rack bay lines generally have to be set to keep uprights off the rail and its bedding.

The practical consequence is that these systems frequently need custom upright heights per run rather than one schedule for the whole building. That is normal work, but it needs to be priced and drawn as such.

The New Class A Buildings on the Same Site

The modern buildings at Bethlehem Commerce Center are a different problem entirely, and a much more familiar one. They run 36-to-40-foot clear with post-tension slabs and ESFR sprinkler protection, built for national e-commerce and consumer-goods tenants.

Those buildings reward building to the cube — tall selective at 32-to-36 feet as a baseline, with push-back, pallet flow, or very-narrow-aisle where SKU velocity justifies the density. The critical constraint is the slab: post-tension construction means steel cables are tensioned inside the concrete, and drilling an anchor into one is both a safety event and an expensive structural repair. Cable mapping precedes every anchor, and most landlords here require documented scanning before drilling.

ESFR protection adds a second constraint. Rack depth, back-to-back spacing, and flue space are part of the sprinkler certification, and top-of-storage clearance to the sprinkler deflector — not deck height — is what actually caps your top beam level.

Heavy Loads and Manufacturing Supply

Not everything on redeveloped industrial land is consumer-goods distribution. The Valley retains a real manufacturing base, and manufacturing supply carries load characteristics that standard distribution rack is not rated for.

Steel stock, castings, machined components, and equipment assemblies routinely exceed what a selective system rated for 2,500 to 3,500 lb per beam level can carry. Heavy-beam selective with engineered anchor packages is the norm rather than the exception in these facilities. Long goods — bar stock, tubing, structural shapes, and lumber — belong on cantilever rather than being forced onto pallets.

Where a facility handles regulated chemicals, solvents, or flammable liquids, storage areas typically require physical separation from general commodity storage under NFPA 30 and IFC requirements, containment decking rather than standard wire decking so spills cannot pass through, and in some configurations a separate sprinkler zone. We design that segregation into the primary layout before drawings are produced. Retrofitting containment and separation into an existing rack layout almost always costs more than building it in.

Permitting in Bethlehem

Rack permits inside city limits go through the City of Bethlehem Bureau of Code Enforcement. Commercial applications require three sets of construction drawings and three site plans, with engineering sealed by a design professional above threshold height and load.

Two local details matter. First, Bethlehem straddles the Lehigh–Northampton county line, so confirming which county a parcel sits in is worth doing before the submittal rather than after. Second, storage above 12 feet triggers high-piled combustible storage review under IFC Chapter 32 as adopted through the Pennsylvania Uniform Construction Code — which is essentially every rack system in a modern building on this site. Submitting the building permit and the high-piled review the same day keeps them concurrent; sequential submittal adds weeks for no reason.

Brownfield conversions can carry an additional wrinkle: where a site has environmental controls or engineering caps from remediation, floor penetrations may be restricted or require coordination before drilling. Confirm this early on any redeveloped industrial parcel — it is not a code question, and it will not surface in plan review.

Practical Steps for a Brownfield Racking Project

1. Survey the real building, not the drawings. Column grid, clear height by zone, crane rails, pits, and trenches all get measured on site. Original drawings for a building of this vintage are frequently incomplete or superseded by undocumented changes.
2. Core the slab in multiple locations before anchor design. One reading is not a profile, and the thin spot governs.
3. Ask about environmental caps and floor-penetration restrictions. On remediated industrial land this can constrain anchoring, and it will not come up in a code review.
4. Expect custom upright schedules. Converted buildings rarely accept one height across the whole system. Price and draw for that rather than discovering it during install.
5. Confirm the county and the reviewing office up front. Bethlehem spans two counties, and Pennsylvania permits municipally — the parcel determines the office, not the mailing address.