Loading docks are the arrival and departure point for large shipments brought to or taken from a building by trucks and vans. The loading dock space type described here includes a shipping and receiving dock for trucks and vans, a staging area, and at least one office space for dock supervisors or managers. This space type does not include light industrial spaces or warehouse spaces, although these spaces can be related programmatically.
Loading docks are utilitarian spaces that should be designed for function and durability. However, it is also important that they are designed to ensure the safety and security of their users and the users of other nearby spaces. This space type must be able to accommodate large vehicles, forklifts, and pedestrian traffic. Typical features of loading dock space types include the list of applicable design objectives elements as outlined below. For a complete list and definitions of the design objectives within the context of whole building design, click on the titles below.
- Access: A ramp should be provided from the loading dock down to the truck parking area to facilitate deliveries from small trucks and vans. This ramp should have a maximum slope of 1:12 and comply with ADA Accessibility Guidelines, ensuring that it may be easily maneuverable for deliveries on carts and dollies.
- Adjacencies: Loading docks must be located for easy access by service vehicles and should be separate from public entrances to the building, public spaces, and other light industrial or warehouse zones. Loading docks must be convenient to freight elevators so that service is segregated from the main passenger elevator lobbies and public corridors. The service route from the elevator should accommodate the transport of large items. Separate or dedicated docks should be considered for food service areas.
- Accommodating Vehicles: Loading docks must accommodate vehicles used to deliver or pick up materials from the building. If the bed height of vans and trucks varies more than 18 inches, at least one loading berth should be equipped with a dock leveler. Typical docks are built 55 inches above grade level to accommodate most trucks.
- Lighting: Each truck position should be equipped with adjustable lighting fixtures for the illumination of the interior of trailers.
- Edge Guards and Bumpers: Loading docks should be protected with edge guards and dock bumpers.
- Exterior Doors: Easy access overhead coiling doors are preferred for loading docks. These doors should be able to close completely and lock after business hours. At least one well lit personnel door should be provided in addition to the overhead doors.
- Noise Exposure Mitigation: Noise reductions in the dock and noise transmission out of the dock are different design considerations. Mass and limpness/flexibility are two desirable attributes for a sound transmission barrier. Unpainted heavy masonry walls provide mass. Absorptive acoustical surfacing will reduce the noise level in the dock but will have little effect on the transmission outside it. Noise levels in the dock should be moderated to promote communication among users.
- Flooring: Resilient flooring should be used in offices adjacent to utilitarian spaces such as loading docks. See WBDG Materials.
- Storm Water Management: The truck's approach to the dock should be at grade or sloped away from the loading dock to prevent the collection of storm water near the dock.
- Weather Protection for Users and Goods: Open loading docks should be covered at least four feet beyond the edge of the platform over the loading berth to protect users and goods being unloaded. In cold climates dock seals should be used at each loading bay. Alternatively, consideration could be given to enclosing the entire loading bay.
- Staging Area: A staging area inside the building should be provided adjacent to the loading dock. It must be protected from the weather. See also WBDG Light Industrial.
- Monitoring Ingress / Egress: A dock manager's room or booth should be located so the manager can keep the entire dock area in view and control the entrance and exit from the building. The flow of circulation into the dock should pass this control point, and access should be restricted to authorized personnel. Security cameras may serve as a back up. See also WBDG Secure/Safe—Security for Building Occupants and Assets.
- Emergency Egress: Loading docks should not be used as emergency egress paths from the building. Additionally, staging areas and associated equipment must not interfere with emergency egress routes from the building. See also WBDG Secure/Safe—Fire Protection.
- Monitoring Deliveries and Shipments: Examination of deliveries should take place in the staging area and should be monitored by the truck driver and a shipping/receiving clerk. Shipping and receiving logs should be kept.
- Blast Protection: Based on risk analysis for the building, the loading dock should be located so that vehicles will not be driven into or parked under the building. If this is not possible, the service area should be hardened for blast. Docks should be separated by at least 50 feet in any direction from utility rooms, utility mains, and service entrances including electrical, telephone/data, fire detection/alarm systems, fire suppression water mains, cooling and heating mains, etc. Locate normal and emergency fuel storage areas away from loading docks. See also Designing Buildings to Resist Explosive Threats.
- HVAC: Consider providing separate HVAC systems for loading docks when there is a significant risk of threatening, internal events. See also Air Barrier Systems in Buildings.
- Accident Prevention: Slips and falls are among the most common types of accidents that occur on loading docks. With the great amount of activity, material, and equipment concentrated on docks, proper maintenance of this space is necessary to ensure user safety. Spills and leaks must be cleaned up immediately; damage to flooring must be repaired; dock plates must be properly placed; trash must be removed and disposed of; containers, packaging, and tools must be kept out of circulation paths; and pedestrian and forklift routes should be differentiated and marked. Note that dumpsters used at the loading dock should be located in a controlled area. See also Sustainable O&M Practice.
- Forklifts: All forklifts should be equipped with lights, front and back, and a horn. In humid conditions or when unloading refrigerated trucks, moisture may accumulate on truck bed creating dangerous, slippery conditions for forklifts. Use mats or a drying agent to prevent slippage.
- Prevent Runaway Trucks: Use chocks, wheel stops, or a hook on the rear axle of the truck to prevent runaway trucks.
- Indoor Environmental Quality: The entrances and exits at loading docks and service entrances should be provided with a means to reduce the infiltration of outside debris into the building. Maintaining a negative pressure in docks, relative to the rest of the building, will help reduce infiltration and enhance indoor environmental quality. See also Air Barrier Systems in Buildings.
- Carbon Monoxide Exposure: Carbon monoxide exposure from trucks and powered material-handling equipment, such as forklifts, presents a serious health risk to employees who work on loading docks. To eliminate or reduce exposure to the gas take the following steps: Instruct truck drivers to turn off their engines when docked; Consider using electric powered fork lifts or electric powered jacks; Install a carbon monoxide alarm and test it regularly; Use local exhaust ventilation to remove carbon monoxide; And, make sure there is enough ventilation to remove carbon monoxide even when doors and windows are shut. For more information see the Carbon Monoxide White Paper .
- Air Intake Ventilation: The placement and location of outside air intakes is critical the health of the occupants inside a building and must be in compliance with the security requirements of the building. Ventilation air intakes should be located no less than 25 feet away from loading docks, garage entries, and similar carbon monoxide contamination points. See also WBDG Sustainable—Enhance Indoor Environmental Quality.
- Radiant Heating: Because loading docks experience high air infiltration loads, radiant heating systems, hot water or gas fired, may be considered in lieu of convective or all-air heating systems as an energy saving measure. Overhead and under-floor type systems are both appropriate.
Relevant Codes and Standards
The following agencies and organizations have developed codes and standards affecting the design of Loading Docks. Note that the codes and standards are minimum requirements. Architects, engineers, and consultants should consider exceeding the applicable requirements whenever possible.
Health Care Facilities, Land Port of Entry, Office Building, Research Facilities, Warehouse
Functional / Operational, Productive, Secure / Safe, Sustainable