I've heard tenant's and landlord's use grade level door and loading dock interchangeably as if they are the same thing. They are not.
Most industrial buildings, units, or space for lease contains a grade level door. It would be rare if a building wasn't equipped with one as they are a standard useful feature. A grade level door opens and closes down to the grade and if that sounds confusing just replace the word grade with ground. The door is level with both inside and outside ground so as you can easily move objects through in and out. Most times these doors are large enough for vehicles to drive through which is an important feature for many tenant's.
The loading dock is different in that the door is truck level and acts as a dock to safely move between building and truck trailer. A transport truck can back its trailer into a loading dock and when parked, it should be possible to enter the truck through the warehouse by flat surface. This makes it possible to load and unload goods quickly, especially with the use of a tow motor or fork lift. Unfortunately loading docks are in demand but have low supply, especially for industrial units under 10,000 sq ft. Compared to grade level doors a loading dock is not cheap or easy to install which is why they are more rare. A property needs to be able to handle truck access to back into a dock as well.
In St. Catharines and the Niagara region it is unfortunately difficult to find loading docks in our current supply of industrial buildings. While there are currently and abundance of grade level doors, it would be good if developers and building owners started recognizing the shortage of loading docks to ensure they are a more common feature for warehouse and distribution tenants needing to rent warehouse space with that feature.