A bridge crane turns a building into a machine, and the structure around it has to be designed with that purpose in mind. The crane rides on runway beams carried by columns or by brackets on the building frame, and the loads from a lifted object are transmitted through the wheels, the runway and the columns into the foundations. A rated capacity of five tons, twenty tons or more is a structural requirement that affects the frame, the slab and the budget, not merely a piece of equipment added at the end.

Crane buildings serve fabrication shops, equipment maintenance bays, precast and manufacturing plants, and some warehouses where heavy items are moved by hook rather than by forklift. Edinburg's industrial districts, including the Edinburg North industrial park, are growing, as the Economic Development Corporation reported when it noted land sales to six companies planning nearly 400,000 square feet of industrial space, but a crane is a reason to consider a building designed for it, not an upgrade added later to a standard shell.

What a crane building includes

The elements are the primary frame with columns sized for crane loads, the runway beams and their rails, the crane itself with its electrification, the foundations that carry crane loads, and a slab designed for the wheel loads of loaded forklifts or trailers. Roof height must allow for the crane's clearance above the hook, and the eave height is often set by the crane, not by the operation below it.

Crane suppliers deliver and install the crane, and we coordinate their schedule with the building. A crane that arrives before the runway is complete cannot be set, and a runway completed without the crane's final dimensions may need field changes. Where the building is a pre-engineered metal building, the manufacturer must be told about the crane before the order is placed, since standard packages are not designed for crane loads without modification.

Electrification is a separate scope. Festoon systems, conductor bars and pendant controls need power at the right voltage, and the electrical drawings must show it. We check that the electrical contractor has the crane manufacturer's requirements and that any disconnect and lockout provisions are located where a maintenance worker can reach them safely.

Control of the work that sets the tolerances

Crane rails must be installed to tight tolerances in elevation, spacing and straightness, since a rail that deviates will cause wheel wear and noisy, unsafe operation. We coordinate the surveyor who sets the rails and require an as-built survey of the runway before the crane is installed.

We also manage the concrete for the column footings. Crane loads create overturning and settlement concerns, and these footings are placed and cured under the direction of the engineer, with testing of the concrete and inspection of the reinforcing. When the structure is a structural steel frame, the erection tolerances are set for the crane from the beginning.

Operating a crane safely in a finished building

Crane safety begins in design, with limit switches, overload protection, guards on exposed electrical equipment and clear access to the cab or pendant. It continues in operation through inspection, training and rules for rigging. We provide the owner with the manufacturer's documentation and the inspection records generated at commissioning.

During construction, the use of temporary cranes to erect the building also requires planning. A mobile crane needs level ground, a clear swing area and a plan for overhead lines. Heavy deliveries, such as the crane bridge itself, may arrive on oversize trucks that need a route and a staging area, and we plan for them with the carrier. We include these in the pick plans and coordinate them with the Edinburg Building Safety Department when public right-of-way is involved.

Permits and engineering review

The City of Edinburg Building Safety Department handles plan review, permits and inspections, and its Fire Marshal applies the International Fire Code and NFPA standards. The department's pages do not state the adopted building code edition, and Texas law makes the 2012 International Building Code the floor for commercial construction, so we ask the department which edition and amendments apply.

A crane building requires engineered drawings showing the crane loads, the runway design and the supporting structure. We submit the crane manufacturer's load data with the structural drawings so that the reviewer can see how the loads were used. Accessibility requirements under the Texas Accessibility Standards apply to projects of $50,000 or more, and we register eligible projects early.

Decisions that are expensive to reverse

The most important decision is the crane capacity, including a margin for future needs. Increasing capacity after a building is built may require new runway beams and reinforced columns, so we discuss the largest object that the owner expects to lift over the life of the building. The second decision is the height under the hook, which determines the eave height and the volume of the building.

The third is expansion. A runway can be extended if the building is lengthened, but only if the end wall and the footings were designed for it. A building with a long runway and wide bays may also be a clear-span rigid frame, and owners considering larger programs can also look at manufacturing facility construction for the other building systems that often accompany a crane.

Start with the heaviest lift

Give us the largest item you will lift and the area it must reach, and we will propose a building to match. Developers weighing industrial sites can see the commercial real estate developers page, and operators can read the background in our manufacturing plant overview.

Questions Owners Ask

Do crane runways need special foundations?

Yes. The columns that carry runway beams support concentrated loads and are subject to repeated loading, so their footings are designed by the engineer for those conditions. We pour them to the engineer specification and verify the elevation and bolt location before the steel is set.

Can an existing building be modified to carry a crane?

Sometimes. The columns, footings and roof framing must be checked for the added loads, and strengthening may be needed. A feasibility study by the engineer is worth the cost before the owner commits to a crane purchase.

How long does the crane itself take to arrive?

Lead times vary by capacity and manufacturer, and they can be longer than the building shell. We ask the owner to place the crane order early and to obtain the load data needed for the structural design as soon as possible.

Is a crane building more expensive than a standard industrial building?

It generally costs more per square foot because of the heavier frame, the runway and the foundations. The extra cost is justified when the operation depends on lifting, and we provide an estimate with the crane features separated so the owner can see the cost clearly.

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