Total rentable square footage of a property divided by the number of parking spaces; typically expressed as a ratio of spaces per 1,000 square feet. As an example calculation, a 40,000 square foot office building with 180 parking spaces has a parking ratio of 4.5 spaces per 1,000sf. Different property types or tenant uses may require different parking ratios.
The ratio by itself doesn’t determine how parking is utilized. More goes into it. Here are a few factors to consider:
Building Type — A large industrial warehouse will have a much lower parking ratio than a retail building. A lot of warehouse square footage is consumed by storage or even machinery. However, an office space of comparable size will certainly have a much higher parking ratio since far more people consume the space
Regulations — Local regulations are always a factor in determining parking spaces. For new builds and based on use, spaces will be allocated per regulations. These spaces will also include parking that might not be utilized as much, such as handicap parking. For an existing building that has already been regulated, new tenants will have to work with the existing ratio unless they are able to get a new permit for different building use and have space to expand the parking lot if needed.
Commute — How people, who occupy the building, commute is another consideration in determining the parking ratio. Do people travel by train, rideshare, or other means that don’t require a parking space? Are those patterns stable? Understanding how people plan to use parking is a major contributor in determining the parking ratio.
Another consideration is the use of reserve parking. In addition to handicap spaces, these are spaces that may not always be utilized. However, unlike handicap spaces, reserve parking is much easier to change into a general parking space.
