Cities and Design

Thursday, April 11, 2024

Shelter Science

Shelter is one of four divisions in both the Urban and Rural Phyla of our Built Domain. It is served by its Movement, Open Space, and Life Support Divisions, and is essential to our survival; but continues to consume our source of life as it sprawls across the face of the planet in an unrestrained belief that land is a commodity. It is a situation that cries out for a more scientific approach to the provision of land for shelter capacity as populations grow and migration patterns continue. (Shelter capacity is gross building area in sq. ft. per related buildable acre.)

Six design categories are all that is needed to begin objective classification of buildings in the Shelter Division. They currently consume land without accurate mathematical correlation to the actual shelter capacity of land, the activities contemplated. The intensity implied, and the public revenue potential per acre consumed.

The land consumed for shelter is at best an approximation related to the parcel or parcels available. Continued land consumption for an expanding Built Domain is leading to increasing recognition that more sustainable solutions must be found to make better use of an essential resource subject to competing demands. Efficiency of land use has been an agricultural preoccupation that is becoming an urban mandate. We have often been concerned with the compatibility of adjacent activity but relatively helpless in the face of expanding sprawl.

The consumption of land for shelter has often produced random sprawl and excessive intensity because the tools needed to measure, correlate, predict, and lead the design and construction of shelter capacity within limited land areas are either missing or uncorrelated. We have attempted to lead the planning and physical design decisions that produce our cities with a legal format steeped in our social history of independent commandments. The result has often been leadership contradiction and confusion because physical design requirements are not independent social regulations. The values assigned to their topics must be correlated with mathematical algorithms before a set of value decisions can efficiently use limited geographic areas to shelter the activities of growing populations when the goal is to protect both their source and quality of life.

A set of correlated design specification values entered in the forecast model template of a building design category defines the shelter capacity, intensity, intrusion, and dominance implications planned or measured. These value topics have been partially recognized but have remained incomplete and mathematically uncorrelated. Shelter science can begin when they are consistently listed, measured, correlated, and evaluated for each building design category and activity group. This can build the knowledge needed to understand, improve, and lead the results produced.

Fortunately, the shelter topics involved can be expressed with equations. The relationship of these equations can be defined with algorithms. This is the mathematical foundation for the building form, function, and appearance that grows from these decisions. The mathematical relationships between shelter and land have always been there, but we have been slow to recognize their underlying presence in the forest of more tactical design decisions that reside within specialties we call architecture, landscape architecture, urban design, city design, and city planning. There is, however, a foundation of mathematical decisions that can be correlated to define the shelter capacity, intensity, intrusion, and dominance of shelter desired long before it grows from the land; and it can be used to lead shelter growth within limited geographic areas. This collection of building mass, parking, pavement, movement, open space, and life support has often been referred to as an urban pattern or composition; but these terms give the impression of organization when the results have more often been scattered sprawl and/or unmeasurable intensity, intrusion, and dominance. Science can begin when measurement becomes feasible.

SHELTER DIVISION CLASSIFICATION

The Shelter Division of a city contains six building design categories classified by the parking that serves them. They are: (1) Buildings with surface parking lots around, but not under, the building on the same property (G1); (2) Buildings with surface parking around and under the building on the same property (G2); (3) Buildings with an adjacent parking garage on the same property (S1); (4) Buildings with underground parking on the same property with or without supplemental surface parking (S2); (5) Buildings with structure parking under the building on the same property with or without supplemental surface parking (S3); and (6) Buildings with no parking required (NP).

The definition of the six building design categories just mentioned is expanded with the design specification topics listed in their forecast models. These topics receive values that are either measured or entered for evaluation of the option represented.

Table 1 presents an example of the G1.L1 forecast model. It pertains to the G1 Building Design Category when the buildable land area in acres is given in cell F3. Think of the listed specification topics and values entered or measured as the characteristics of a species. When topic values are processed by the algorithm in the design specification template of the table, the master equation in cell B39 uses the results to calculate gross building area options in cells B44-B53 that are related to the floor quantity options entered in cells A44-A53. For instance, a five floor building on line 48 of Table 1 is predicted to produce 24,226 sq. ft. of gross building area given all specification values entered in its Design Specification Module. A change to one or more of these values will produce a new set of implication predictions.

The G1 building is further classified by the shelter capacity, intensity, intrusion, and dominance calculated in the Implications Module of Table 1. The five floor option, for instance, has a shelter capacity of 13,939 sq. ft. per buildable acre; an intensity rating of 0.836, a vertical intrusion rating of 1.0, and an overall physical dominance rating of 1.836. If the projected total revenue potential from its occupant activity were $10.00 per gross sq. ft., total revenue of $13,939 could be divided by the 1.738 buildable acres calculated in cell F10 to predict a total revenue potential, or yield, of $8,020.14 per buildable acre. Comparing this to a city’s total annual expense per buildable acre would reveal its place in a city’s total revenue investment portfolio.

In other words, the land is more than a commodity to a city and its use is more than a socially compatible consideration. The combination of permitted shelter capacity, intensity, activity, and economic potential are an investment in its future. Decisions regarding the allocation of shelter capacity, activity, and intensity in its urban design plan determine the quality of life it can provide.

HOW MUCH LAND IS NEEDED

A shelter capacity question does not always involve the potential of a given land area. The buildable land area needed for a given gross building area objective is also a question that can arise.

The answer begins with the selection of a building design category forecast model. In this case I’ve again chosen the G1 Building Design Category but am using Table 2 to address the question. It contains forecast model G1.B1 and uses the same shaded cell designation for design specification values. The optional values entered are used to further define the question with a complete description of the classification characteristics proposed.

Table 2 is based on the gross building area objective entered in cell A34. The values entered in the remaining gray cells represent one set of correlated design specification options, and a change to one or more of these values will produce a new forecast of necessary buildable land area alternatives in cells B44-B53. These alternatives are related to the floor quantity options entered in cells A44-A53 and are converted to buildable acre options in cells E44-E53.

The implications of the values entered in Table 2 are calculated in its Implications Module. This makes it possible to measure and compare the mathematical physical design decisions that determine the shelter pattern, spaces, and composition of cities with their social and economic implications long before building appearance becomes an issue.

THE MASTER EQUATIONS

The master equation in cell B39 of Table 1 is one of a number derived to predict gross building area implications from a set of design specification values entered in the gray cells of a building design category forecast model. I’ve only shown one in Table 1 and one in cell B39 of Table 2. The entire Table of Contents is presented as the last exhibit in this essay. It is not included to display the master equations, however. They require greater explanation related to their forecast models. It is included to show classification of the Shelter Division by building design category and activity group.

A building design category is occupied by an activity group. The combination may require that additional design specification topics and values be added to its forecast model when it is amended to address a specific activity group. The Residential Activity Group in the Table of Contents illustrates the forecast models that address an activity group when it occupies the fundamental building design category options listed above.

In other words, gross building area is subdivided to serve an activity group. The shelter capacity, or gross building area per buildable acre, of the land area remains the same; but the internal capacity of the gross building area to serve a specific activity group will be affected by the group’s floor plan requirements. Gross building area is determined by the design specification values entered in a building design category’s design specification template. The shelter capacity of land and the intensity options considered are a function of these values. These are the strategic shelter design decisions that combine with movement, open space, and life support decisions to determine the spaces, places, and building mass that surrounds us in an urban pattern that cannot be permitted to consume our source of life.

The internal capacity of gross building area is a function of the activity’s program of floor plan requirements. This is the beginning of tactical architectural design decisions that are correlated to produce the form, function, and building appearance we recognize.

The master equations related to each building design category pertain to every potential activity group that may occupy the category. They make it possible to measure and forecast the implications of correlated mathematical design decisions in a fraction of the time it takes to prepare one schematic drawing; and the time-consuming drawing has always been limited to an intuitive, visual understanding of the implications depicted.

There are many activity groups that remain unrepresented in the attached Table of Contents, but group specifications only relate the capacity of gross building area to serve the demands of a specific activity. Keep in mind that gross building area may be occupied by any activity. The shelter capacity of land is a function of the gross building area present or planned. The scope of present or planned shelter capacity, activity, condition, and location of gross building area on land determines the value of the buildable acres to a city’s revenue investment portfolio; and the land’s ability to contribute to a city’s quality of life. The ultimate objective is to provide an economically balanced city design model of shelter capacity and intensity to finance the activities of growing populations within geographically limited areas defined to protect both their quality and source of life.

W. Martin Hosack: April, 2024

Friday, March 29, 2024

The Value of an Acre

The value of an acre is often considered in relation to its profit potential as a commodity, but rarely considered in relation to its public revenue potential as a shared investment in the future.

INTRODUCTION

There are few, if any, municipal jurisdictions equipped to accurately appraise the revenue potential of acres within their zones at the present time. They know what they are producing but they cannot accurately predict potential options. They may not even know their total average annual expense per acre. This means they cannot accurately compare or plan to adjust the revenue produced in relation to the increasing cost of their operations, maintenance, improvement, and debt service.

If the total annual revenue received from a property owner were converted to the revenue received per buildable acre owned, it could be compared to a jurisdiction’s total annual cost of operations, maintenance, improvement, and debt service per buildable acre. If it were, we would have a much better picture of a city’s economic health at the cellular level of its anatomy - and the development strategy needed to maintain or improve this performance in the future.

Public revenue in this context is the total revenue per gross building area square foot that can be expected from the activity planned, present, or permitted. It would be unrealistic to expect that every property and every zone in a city would be producing surplus revenue per buildable acre when compared to a city’s total annual expense per acre, but the combined average must produce the total public revenue per acre required to avoid future reductions in service.

Most cities rely on past history and future projections built on a history of expense that either ignores, or is unaware of, the true cost of annual infrastructure maintenance, to say the least. Annexation makes new revenue look like the answer until age again begins to increase its total service and maintenance expense per acre. The annexation trap is easily concealed by the years it takes to emerge as a problem, but the absence of analytical data makes it a potential Ponzi scheme based on expedient solutions from short-term office holders and hope that this revenue will be adequate; but hope has never been a strategy.

THE THREE-DIMENSIONAL ISSUE

The problem is three-dimensional. It has been called “urban design” or “city design” and is generally placed in the realm of fine art since the options have had a subjective foundation defended with opinion and experience. I have written many essays explaining that the options can be defined with mathematical algorithms. They are used to correlate related design specification values entered in the specification module of a building category forecast model. The master equation in the model produces a forecast of the shelter capacity, intensity, intrusion, and dominance implications implied by the values entered. Optional implications can be tested by changing the values entered with a few keystrokes.

Shelter capacity is occupied by activities that have revenue implications. At the present time this is more of a guessing game than the product of rational evaluation and comprehensive planning. We are faced with isolated data silos and missing relational databases that are needed to correlate shelter capacity and intensity options with the revenue potential of permitted activity.

ECONOMIC PERFORMANCE

Economic performance is partially a function of the building capacity available or permitted per buildable acre to shelter taxable activity in a city. Some of these acres shelter activity that produces less than a city’s average annual cost per acre. Some produce far more, but there is no three-dimensional display that correlates shelter capacity, activity, intensity, and context with the revenue needed to sustain a desirable quality of life within geographic limits.

Before I go any further, “shelter capacity” is gross building area in sq. ft. divided by the buildable acres allocated to serve the building. Physical “intensity” is shelter capacity times the total impervious cover percentage present or planned divided by 10,000. If this is confusing, please refer to some of my earlier essays that discuss building design categories, the components of their shelter capacity forecast models, and their predictions in detail.

The challenge to produce an inter-active, three-dimensional display of shelter capacity, activity, intensity and economic performance is not a simple one. The prediction of options can only begin with a new mathematical ability to predict the gross building area alternatives associated with optional design specification values assigned to a given building design category forecast model and land area. Math is the foundation for correlated urban design and economic development evaluation since gross building area options can be occupied by any activity, and the relationship of building area to occupant activity sets the stage for revenue potential.

The standardized value topics in a forecast model can also be used to measure, record, and evaluate the shelter capacity of existing parcels on a systematic basis, and correlate these measurements with their calculated intensity and context implications.

Our inability to correlate building design categories and design specification values for every acre within a city has handicapped our ability to correlate shelter capacity, activity, and intensity to achieve and adjust the economic performance needed to support a desired quality of life for growing populations within geographic limits. In my opinion, sprawl and excessive intensity have resulted from this inability to correlate design decisions with the math that is an unrecognized foundation for the leadership decisions involved.

POSTSCRIPT

An acre has a higher value when slated for consumption as a commodity than when designated for preservation as a source of life. This is logic that begs for appraisal on a planet that will enforce its Law of Limits without compromise.

Walter M. Hosack: March, 2024

Sunday, March 17, 2024

How to Transition from Zoning to Urban Design

I was recently asked the question in this title and thought I’d publish my answer.

INTRODUCTION

Urban design begins with mathematical relationships between the geometry of building mass and the two-dimensional quantities of building footprint, pavement, parking, and unpaved open space. They are combined and arranged to form a building site plan. Elevations are needed to define the building mass implied by the building footprint in the site plan. A collection of these plans defines the shelter anatomy of neighborhoods, districts, cities, and regions served by arteries of movement, open space, and life support. (Arteries of public open space are more of a dream than reality but their absence compromises the health of the anatomy in my opinion.)

It’s time to learn about the mathematical correlation required to understand and lead the shelter compositions we create within a randomly growing urban anatomy. We cannot lead without a more precise, comprehensive, and correlated mathematical language capable of the measurement, evaluation, debate, prediction, and planning required to guide our habitat toward a symbiotic relationship with its source of life.

There are only six building design categories when classification is based on the parking system planned or present. This classification makes shelter capacity measurement, evaluation, planning, and forecasting mathematically predictable. (Shelter capacity is gross building in sq. ft. divided by the buildable acres of the property.) I have mentioned these categories in many essays and request patience from those familiar with the topics as I repeat them here. They are: Buildings with surface parking lots around, but not under, the building on the same property (G1); Buildings with surface parking around and under the building on the same property (G2); Buildings with an adjacent parking garage on the same property (S1); Buildings with underground parking on the same property with or without supplemental surface parking (S2); Buildings with structure parking under the building on the same property with or without supplemental surface parking (S3); and Buildings with no parking required (NP).

Buildings are classified by design category in the attached Table of Contents. I’ve included the table to illustrate the range of forecast models currently available to measure, evaluate, predict, plan, and lead the formation of shelter within geographic limits defined to protect their source of life.

The master equations noted in the attached Table of Contents have been derived under separate cover for future evaluation. The forecast models shown greatly improve the models I included on a CD in my first book, Land Development Calculations, 2001 published by McGraw-Hill. I have had requests for the first edition CD from some who can no longer find it with a used book. As far as I know, the second edition still contains a more complicated CD and is available from both McGraw-Hill and Amazon.com.

I cannot provide copies of the first edition CD on request because: (1) It was prepared using an older version of Excel and I’m not sure it will still run. (I haven’t used it for years); and (2) The CD was often copied. As a result of this experience, I will only provide the new algorithm-based forecast models to an investor willing to place these inter-active models on a subscription based web site.

The gross building area options predicted per buildable acre by these models is based on optional design specification value entries. The results are a keystone consideration, since they define the shelter capacity, intensity, and revenue/income potential per acre. The type of activity planned or present within gross building area determines the economic potential of the shelter capacity options and intensities predicted per buildable acre. This potential revenue per acre can be compared to a city’s total annual expense per acre when its annual budget is divided by the taxable, buildable acres within its limits.

The relationship between a buildable acre and the gross building area present, planned, or predicted determines the shelter capacity of the acre. Occupant activity determines its revenue potential, and gross building area may be occupied by any permitted activity. A land use plan solely focused on compatible activity relationships leaves its economic future to chance since gross building area results are left to chance.

Economic development does not need to be a reaction to budget deficits. It can be part of a forward-thinking master planning effort when its decisions are mathematically driven. In other words, shelter capacity and activity must be mathematically correlated before economic potential can be more than hope that has never been a substitute for strategy.

It all begins with the choice of a building design category for a given land area and the optional values assigned to the design specification topics within its forecast model. Embedded algorithms correlate these values with the floor quantity options entered to produce a table of gross building area, shelter capacity, intensity, intrusion, and dominance implications. The activities that can be accommodated by these gross building area options have economic options and implications. It is in both the public and private sectors interest to correlate these shelter capacity, intensity, and activity options to produce economic results capable of consistently supporting a desirable quality of life within geographic limits that protect their source of life.

The gross building area capacity of a buildable acre is a function of the building design category chosen and a limited number of design specification topics and value options. This specification palette, however, produces a relatively infinite number of desirable and undesirable shelter capacity and intensity possibilities. Correlating these options to produce physical, social, psychological, environmental, and economic security without threat to our source of life is the challenge we face on a planet that does not compromise with ignorance.

THE ANSWER

The transition from zoning to urban design will begin with the recognition that zoning has a mathematical foundation that must be distilled and correlated to become a successful leadership language. It has been a step in the right direction but urban design specifications are not like social regulations. They require mathematical correlation. I have often found that the currently absolute and incomplete zoning design regulations have simply led to contradiction and confusion. This appears to have contributed to the sprawl and excessive intensity we find in many of our cities.

Think of urban design as a mathematically correlated policy statement for each cell in an urban anatomy that cannot continue to randomly metastasize without consequence. This growth has been referred to as urban form, urban pattern, and urban composition, but these terms give the mistaken impression of organization. The only appropriate and accurate term has been “sprawl” enabled with legal annexation as an expedient solution for the growth we encourage with an inadequate understanding of the consequences.

Mathematical urban design decisions have physical, social, and economic implications that remain to be discovered through measurement, evaluation, and debate. The policy decisions adopted will be symbolized by the form, function, and appearance built on this foundation.