Trailer Types

Truck Bed Height
A typical loading dock may at some point service every type of vehicle on the road. It is essential to recognize the characteristics of the trailers that will be visiting the loading dock with the highest frequency. This determines the most appropriate design for the dock itself.

Secondary consideration must be given to vehicles that visit the dock with less frequency. If it is a captive fleet (only one style of trailer) being serviced at the facility, then the choice of design is simple. However, due to the range of vehicles utilized by freight companies and product suppliers, it is vital to consider all of the possible variations that can occur.

Truck / Trailer Type	Load Bed Height Total Range MIN \| MAX
Container	56"	62"
Refrigerated	50"	62"
Double Axle Semi-Trailer	44"	52"
City Delivery	44"	48"
High Cube Van	36"	42"
Furniture Van	24"	36"
Step Van	20"	20"
Panel Truck	20"	24"
Straight Truck	36"	48"
Flatbed	48"	60"

Sea Containers
Facilities that must accommodate sea container freight need to be particularly flexible. Sea containers and refrigerated containers can have trailer heights of up to 62". At the same time these facilities may service frequent deliveries/pickups by tailgate trucks and low bed trucks. The height difference can be as extreme as 30" at the low end and 62" at the high end. Consideration must be given to multi height dock designs or the installation of equipment such as a hydraulic dock leveler or an elevating dock.

Pit projection should be increased a minimum of 1” for every 1% of grade on a decline approach of 4% of grade or higher. For declines of 1%-3% of grade, bumper projection may be required using build out blocks, extensions or thicker bumpers.

Note: If building wall projects past dock face, greater dock bumper projection should be considered.