The shelter
capacity, or gross building area capacity per buildable acre of land, has not
been mathematically predictable. The result has been arbitrary consumption based
on the erroneous assumption that land is an expendable and inexhaustible
resource. If we are to limit the land consumed for shelter on a planet that we
must share, site planning for shelter will require correlated mathematical decisions
that accurately define the shelter capacity of land for growing populations
within geographic limits defined to protect our quality and source of life.
The equation derived to measure and predict the gross building
capacity of land for the G1 Building Design Category is an illustration of the
correlation required for measurement and prediction that can be used to
calibrate the implications involved. (The G1 Building Design Category includes
all buildings served by a grade parking lot around, but not under, the building
on the same premise.) This equation and all others derived in my book, “The
Equations of Urban Design”, illustrates the correlation required to improve the
leadership decisions and implications that surround our consumption of land for
shelter capacity. I’ve introduced this equation on many occasions and repeat it
here for reference.
GBA
= ((af) / (a + fs))) * CORE G1.L1 equation
When:
1) (GBA) equals gross building
area in square feet.
2)
(a) equals the square feet of gross
building area planned or permitted per parking space provided.
3)
(f) equals the floor quantity planned
or permitted.
4)
(s) equals the total surface area
planned or permitted per parking space.
5)
CORE equals the buildable land area
(BLA) remaining for surface parking and building footprint (BCA) in sq. ft. after
all other paved and unpaved surface areas are subtracted from the buildable
land area available.
USE OF THE EQUATION
Table 1 is based on the premise that a designer knows the gross
building area required and is entering percentage estimates in the gray cells
of the table to estimate the core land area needed in cell F34. (Core land is
the land remaining for building footprint and parking on the buildable land of
a property.) Transposition of Equation G1.L1 produces the equation needed to estimate
the buildable land area required, except when common open space is provided.
(This exception will be explained in the ensuing text. In this example,
buildable land area and shelter land area (SHA%) are equal and derived in cell
F18 of Table 1. Shelter area is the land remaining after shared open space
among property owners is subtracted from the buildable land area available.)
CORE
= BLA%
BLA%
= GBA * ((a+fs) / (af))
BLA
= (((GBA * (a+fs))) / (af))) / BLA% Equation G1.B1
Table 1 has been created to find the buildable land area options
(BLA) that can satisfy the design values entered in the gray cells of its
Design Specification Template. The panel has been specifically designed to
illustrate the correlation between design specification values entered and the
zoning requirements permitting gross building area in Col. A of the table. Keep
in mind that a change to one of more of the design specification values entered
will produce a new set of results in the Forecast Panel.
The percentage values entered in the shaded cells of the Design
Specification Template are mathematically correlated to produce the CORE
percentage needed in cell F34. In this case it is shown as 57.6% of the shelter
area (SHA) calculated in cell F18. Shelter area can be considered the buildable
land area needed (BLA) when no values are entered into cells F14 and F15.
When 57.6% is entered in Equation G1.B1 along with an (a) value
selected from cells A41-A45, an (s) value selected from cells B40-L40, and the
(f) value entered in cell (F36), the intersection of (a) and (s) in the table
indicates the core area needed in acres; the shelter area needed in acres; and
the buildable land area needed in acres.
The point is that all design decisions entered in the gray cells
of Table 1 must be correlated with the (a) values stipulated by a zoning
ordinance in Col. A to produce the results shown in the Forecast Panel of Table
1. Trial and error correlation without the equation involved cannot produce
consistent results. They will always be based on random intuition, talent, and
opinion rather than consistent measurement, research, evaluation, and
application of accumulated knowledge.
An intuitive proposal will often attempt to limit the unpaved open
space percentage provided in cell F12, the area per
parking space (s) chosen in row 42; and argue over the gross building area permitted per parking space (a) in Col. A of the Planning Forecast
Panel. The implications can be easily overlooked when plan review is based on a
visual examination and a limited number of design specification topics.
In other words, the Forecast Panel results shown are produced by
the mathematical correlation of all shaded cell values entered in the table.
These values do not operate independently, but their mathematical relationships
remain undefined in most, if not all, zoning ordinances. Trial and error are where we often
find ourselves, and it has often led to unintended
results.
The fact that mathematical correlation is ignored in a zoning
ordinance guarantees that measurement, research, evaluation, knowledge
accumulation, and leadership improvement will continue to depend on inconsistent
intuition, opinion, and talent.
OBSERVATIONS
Table 1 is a mathematical definition of the intuitive process a
designer uses to approximate the buildable land area required for a gross
building area objective. When Table 1 and Equation G1.B1 are missing, shelter
design becomes a guessing game over the values required to fit a shelter
objective on a given land area. This includes the (s) value to be chosen and an
argument over the (a) value that applies.
Current design efforts often attempt to minimize the (s) value
chosen on row 42 of Table 1 in order to increase the parking spaces that can be
provided. This maximizes the potential gross building area on the least
buildable land area, but does not consider the shelter capacity, intensity,
intrusion, and context implications involved.
TABLE 1
In this example, the gray cell values entered define one
alternative for the shelter design objective entered in cell F36. The issue
being evaluated involves the gross building area permitted per parking space
provided (s) shown in bold in Column A of the Forecast Panel; and the parking
lot design options represented by the parking lot area per space choices (s)
entered in the gray cells on line 42 of the panel.
When a parking area per space (s) is chosen in Table 1, the
buildable land required (BLA) decreases with every increase in the gross
building area square feet permitted per parking space (a). This is the
correlation any experienced designer would expect but cannot accurately
predict.
When a parking lot area per space (s) increases on row 42 of Table
1, the buildable land area required also increases when the gross building area
permitted per parking space (a) remains constant. Again, this is the
correlation any experienced designer would expect but cannot accurately
predict.
In both examples above, the variables entered in the gray cells of
Table 1 from cell F5 to F37 have remained constant. The fact that any one or
more of these values can also change should indicate the complexity of mental
correlation involved with the simplest of building design categories.
INTENT
The intent in this essay is to illustrate the correlation between
zoning ordinance regulation and the parking lot design options available. A
greater (s) value indicates more parking lot area devoted per parking space and
more ability to introduce landscape moderation for the pavement introduced. A
greater (a) value indicates more gross building area permitted per parking
space provided. Three rows of calculation are adjacent to each parking
regulation (a) and beneath each parking design value (s). The first row at the
intersection of the related cells indicates the core area calculated in
response to the variables entered in the gray cells of the table. The second
indicates the shelter area needed and the third indicates the buildable land
area needed in acres. (Shelter area equals buildable area when the values in
cells F14 and F15 are zero.)
The table is intended to show that we cannot leave shelter design
decisions isolated and disconnected at a time when we are beginning to realize
that every acre has a role to play in our sustainable future. The concept of “minimum
reasonable standards” based on the intuition, talent, experience, and opinion of
reasonable men is no longer adequate. Unwritten natural limits are involved. A
credible leadership language based on mathematical correlation and a body of
acquired, correlated knowledge is needed to avoid excessive shelter, movement,
open space, and life support consumption of the Natural Domain, in my opinion.
CONCLUSION
Shelter design has been, and still is, an intuitive guessing game that
attempts to fit a gross building area, or a subdivision, on available land
area. The objective is often to answer the question, “will it fit” or “how much
will fit”. The “highest and best use” of land has been an economic concern. We
are only beginning to expand these questions to encompass the planet where we
live -- and the realistic shelter capacity of a Built Domain that must learn to
share the land with its source of life, the Natural Domain.
Equation G1.L1 and all others that are part of shelter capacity
evaluation, or Tegimenics, have been derived to offer an alternative to the unlimited,
uncorrelated, and approximate consumption of land that has often resulted in either
sprawl or excessive intensity. Damage done by occupant activity is another
issue.
The land required by the Natural Domain involves far more than
scenic attractions, in my opinion. The question deserves a better answer that will
accommodate all dependents.
POSTSCRIPT
The unpaved open space value entered in cell F12 of Table 1
deserves special mention. It is often ignored as an impediment to maximum
shelter capacity achievement. The correlation is significant however, because paved
and unpaved open space combine with landscape improvement to provide relief and
reduce storm sewer capacity demand, as well as potential flooding. These are
essential considerations in my opinion but can obstruct the quest for “highest
and best” economic benefit.
I have no standards to recommend. I simply point to paved and
unpaved pedestrian open space for pedestrian relief as a topic of pivotal
concern that is worthy of context measurement, evaluation, and recommendation.
It can only be provided at the expense of shelter capacity when considering
some building design categories. In these cases, capacity can only be recovered
with increased floor quantity. The correlation deserves our attention because
the tenements of past centuries have proven that we can blindly respond to
economic incentive without consideration for the context created.
Walter M. Hosack, March 2026
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