Interior truck docks are a common sight in Chicago area industrial buildings. In industrial buildings designed since the early 2000s however, interior truck docks have all but disappeared. Virtually all new buildings feature exterior docks only. There are many reasons for this switch:
the building space wasted simply for the transfer of products that may not enhance overall operations;
the added expense for real estate taxes, insurance and repairs for the extra space under roof;
the need for increased ventilation from exhaust trapped inside the building envelope;
the difficulty and extra effort needed to back trailers into tight spaces;
the cost to repair damage from the occasional mishap;
problems with water infiltration and the need to clean up the snow, ice and slush.
For older buildings designed with shorter trailers in mind, the dock bays are not even long enough to accommodate a 55-foot load. The doors must be left open, wasting energy, defeating the whole purpose of an enclosed dock. Additionally, if accidently closed while a truck is parked, the door or the truck, or both might be damaged. Weather seals are a more practical alternative that don't entail wasted space.
According to Brian Carroll, Executive Managing Director of Newmark Grubb Night Frank, a commercial and industrial brokerage firm, a typical interior dock averages about 14' x 65' feet plus some common area or about 1,000 square feet of building area. Most of the time these spaces sit unused and owners continue to pay property taxes on largely empty space.
In comparing older properties, most buildings of similar vintage will share the same obsolescence issues; so that the presence of interior docks may not noticeably impact rent or sales price. Still, numerous interior docks could warrant adjustments.
The 1990s constructed industrial building is most heavily impacted by this issue. While on the surface they may share otherwise similar features, the provision of interior truck docks and loading configuration has changed from the 1990s to the 2000s. Due to this design difference, 1990s buildings may have much longer marketing times and command lower rents than would otherwise be expected due to just the age difference alone. According to Brian Carroll many prospective buyers would zero out the square footage taken up by the drive-in-doors and base a purchase on the building square-footage less the interior truck space, or at most give it up to half credit. For taxation purposes, this could lead to over assessment if compared on the basis of number of dock doors only, without the analyst's consideration of the type of loading facility as well.