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Saturday, January 28, 2017

Abdicating Surface Parking Requirements

Parking requirements have been considered a function of occupant activity since the introduction of zoning regulations. The concept has maintained that more intense activity requires more parking spaces. For instance, 1 parking space might justify 50 gross sq. ft. of restaurant activity or 200 gross sq. ft. of office activity. The concept, however, has produced two intractable problems: (1) The requirements are averages that are not tailored to the needs of a specific enterprise, and (2) The requirements do not solve pre-existing conditions that flood neighboring areas with incompatible overflow parking demand.

In both cases, land is the underlying issue. In new construction, a parking requirement can reduce the land available for a building footprint and the gross building area that can be constructed. In existing areas, there may be no land available to provide adequate parking. There will never be a perfect parking solution given the two problems noted, but the lack of perfection is not an excuse to ignore a fundamental problem as proposed in the following quotation:

Off-street parking should be a business decision, not a government decision.

Business is not motivated by the public interest, and I will argue that adequate parking for successive owners has significant public implications. It may help to begin by explaining the place of parking in a site plan and the design specification values that combine to produce its need for land.

New Construction

All land areas contain various percentages of four ingredients: (1) Unbuildable land area, (2) Buildable land area, (3) Common, or shared, buildable land area, and (4) Shelter land area. When common areas are not provided, buildable land area is equal to shelter land area.

Shelter land area contains various percentages of five ingredients, and one or more of these percentages may be zero: (1) Unpaved open space, (2) Service pavement, (3) Social pavement, (4) Parking pavement, and (5) Building footprint. When shelter is the issue, the first three layers are subtracted from the shelter area remaining to find the core area available for parking pavement and building footprint. The ratio between parking and footprint area combines with floor quantity to determine gross building area potential.

In other words, parking quantity determines the gross building area that can be constructed. Each additional parking space permits additional gross building area, but reduces the surface land area remaining for the building footprint. The building increases in height with a smaller footprint to accommodate the increased area permitted; but the relationship between parking and footprint stops producing meaningful increases in gross building area above five stories, when all other design specification values remain constant.

The shelter capacity of land is the gross building area that can be constructed per shelter acre. It is a function of design specification decisions that are correlated by an architectural algorithm for use in a master equation. The equation pertains to the design category under consideration and predicts gross building area options based on four variables:

1) The gross building area permitted per parking space (a), also known as a parking requirement.

2) The number of building floors under consideration (f).

3) The estimated gross parking lot area per parking space, (s).

4) The core land area available for parking lot and building footprint area after estimates for all other site plan areas have been subtracted (CORE).

The Design Specification Template in Table 1 pertains to the G1 Surface Parking Design Category and illustrates the calculation of core area in cell F32. The parking requirement (a) is entered in cell F34. An estimate of gross parking lot area per space (s) is entered in cell F33. Building floor quantity options (f) are noted in cells A42-A51. The master equation in cell A37 predicts gross building area options related to building height options in cells B52-B51. This is the point when the impact of a parking requirement becomes clear - and the point when it becomes vulnerable to variance requests when it does not produce a desired gross building area. This is not the only option, however. Since there are 25 specification boxes in the table, values can be modified to pursue change in many ways, but the design specification template in Table 1 is not in common use. In its absence, the expedient owner choice has been to reduce the parking provided to increase gross building area, but this can sacrifice its usefulness to successive owners and its public revenue potential over time. Since the city is essentially a farm, the yield from each of its acres determines the quality of life it can afford to provide.

Table 2 is based on a core area of 24,829 sq. ft. and an estimate of 400 sq. ft. per parking space. It presents a range of parking requirement options (a) on line 4. When these values are entered in cell F34 of Table 1, the table produces the gross building area options displayed in columns B-Q. If an owner had a choice among the parking requirements listed on line 4, most would choose the regulation that produces the desired gross building area with the least building height. The number of parking spaces might prove inadequate, but they would choose to live with the result and hope for the best. This is not necessarily in the public interest, however. A failing activity leaves a vacant building with inadequate parking that consumes potentially productive acres. Parking is an essential ingredient in this equation and its impact is felt long after the original owner’s departure.

In other words, a building owner is a temporary investor in shelter for activity on a given land area; and may also be a total or partial occupant of the premises. The building represents a permanent source of public revenue that fluctuates with location, condition and succeeding occupant activity. Under these circumstances, a privately owned building is a public resource that can be compromised by a parking quantity that proves insufficient for future activity. The City of Buffalo, NY has chosen to make parking quantity a business decision. We will never understand the impact until knowledge emerges from the adoption of scientific measurement, evaluation, and forecasting techniques.[1]

Pre-Existing Conditions

A city is an anatomy that grows at the cellular level of property ownership, and it surrounds its defects when there is land to annex. Unfortunately, a sprawling city does not learn to correct its mistakes and control its tendency to consume and pollute the land that is its source of life. In a way, sprawling cities represent an attempt to return to the farm where open space is abundant and equipment can be stored conveniently. Property in a surrounded city cannot expand, and density is magnified by increasing movement and decreasing open space donated to parked cars.

It is inevitable that business would attempt to serve residents in these areas under the deficient conditions created by the automobile, but decline is inevitable when intensity exceeds the limits of tolerance for those who can afford to escape. Columns G-J in Table 1 show that physical intensity, intrusion, and dominance are functions of 25 specification values that can be measured.  In my opinion, the physical conditions created by these specification values affect our social, psychological, environmental, and economic quality of life. They combine within each property cell, and every cell combines with others to form the Shelter Division of The Built Domain. This division is served by Movement, Open Space, and Life Support Divisions within a currently pathogenic anatomy that is encouraged by our concepts of annexation within a world without end. My point is that the parking values in cells F33 and F34 are two of these 25 specification values. They are generalizations when related to a specific activity, but they cannot be ignored and deferred to private enterprise as an expedient solution to an intractable problem that currently affects our quality of life and will affect our symbiotic future.

The problem stems from the fact that we have not been able to predict the shelter capacity of land with any degree of accuracy, and capacity is a function of parking requirements. The only certainty is that parking is an inescapable consideration in the age of the automobile.  

Buildings with no on-site parking have deferred their requirements to others in near-by and remote locations. These locations are provided and connected to exempt building activity at public expense in many cases. The parking requirement did not disappear. Its expense was simply shifted. When expense is shifted to the public side of the ledger, it is subsidized by the average revenue received from all municipal acres. If revenue is inadequate to meet expense over time, government is considered profligate. Budget cuts ensue and decline takes another step toward blight. Inadequate parking will continue to add a largely unrecognized burden to surrounding neighborhoods and municipal expense until this relationship is recognized. A city washes it hands of the problem when it defers parking decisions to private enterprise; but expedient solutions have a way of producing unintended consequences, and we cannot continue to consume land and leave our mistakes in an expanding core of blight.
It is time to come to grips with the true shelter capacity of land and its economic implications. Growing populations will never learn to live within symbiotic limits that protect their quality and source of life until they build the knowledge required, and this knowledge will not be produced by the expedient solutions of private enterprise.

[1] Hosack, Walter M., The Science of City Design: Architectural Algorithms for City Planning and Design Leadership, CreateSpace, 2016. (Available in paperback and e-book versions from

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