Hi Sarah. What I understand is that the U-shaped warehouse layout is more commonly seen. The loading docks tend to be on one side of the facility.

There are also warehouses with loading docks on both sides, thus forming the I-shape. In such situations, inventory are unloaded and staged on one side (inbound), and outbound on the other side.

Advantages of U-shaped warehouse
1. Easier to manage security. Single access.
2. More space for storage.

Advantages of I-shaped warehouse
1. Clear segregation of inbound and outbound.
2. Smooth inventory flow within the warehouse.

Lots of conventional warehouses are U-shaped. One of the reasons is because it is easier to plan for the traffic flow outside the facility.

I-shaped warehouse are more commonly used for cross-docking, where the number of docks availability are critical.

U-Shaped warehouse is better than the other. because, U-Shaped warehouse is easy to manage.

Agreed. I-shape warehouses are more difficult to handle as there are multiple entrance/exit to the facility. Security needs to be ensure.