Monday, January 30, 2012

Recalling Michelangelo

***Please see my latest book, The Science of City Design: Architectural Algorithms for City Planning and Design Leadership, on in both e-book and paperback versions.***

Michelangelo’s statue of David represents the dignity of man as he faces adversity, at least in my opinion. The Borgia conflict was simply the stimulus for his universal statement. If we moved David to a congested street corner festooned with the baggage of commerce and traffic control, it would corrupt his message -- like the tenements and crowded streets of Manhattan corrupt the message from architecture. Moving David from the Piazza della Signoria is my attempt to illustrate that intensity can overwhelm a message that depends on context. 

The open space of The Natural Domain sits on one side of the context scale. Four divisions of The Built Domain are on the other. The design of these four divisions: Shelter, Movement, Open Space and Life Support will determine the balance we achieve and the message we send. From this perspective, architecture is shelter with a message. It is not an object of privilege. It creates space within its domain, but its context will continue to suffer from excess; and survival will hang in the balance, until its public message is recognized at the intersection of speculation and survival.

We must be able to measure intensity, understand its implications and predict alternatives before we can pursue the city design of context and capacity in the public interest. Context, capacity and intensity affect our quality of life within The Built Domain. Balancing these elements involves design specification values, public debate and regulation. Without adequate regulation, we will be left with isolated sculptures of achievement in blighted wastelands of speculation. In fact, many urban areas have already achieved this dubious distinction with inadequate information, incomplete knowledge, uncoordinated regulation and the random application of opinion.  

From this perspective, massing context, capacity and intensity is the first order of business for architecture and city planning. It is needed to produce adequate city design compositions that yield physical, social, psychological and economic stability. The Michelangelos among us can then release form, function and appearance from massing to enhance the places created and message intended. In my opinion, it is the only strategy that has a chance of sheltering growing populations within a limited Built Domain that does not threaten its source of life – The Natural Domain. 

If David sits on a street corner, his photograph must be carefully composed. I don’t know how many times I’ve been surprised by the context of an architectural masterpiece after studying its picture in a history book. This alone convinced me that there is another dimension to architecture. I am not the first to call it city design, but it has little financial support because urban composition has been left to the marketplace -- and the inadequate design of zoning regulation. The result has been a context of sprawl, intensity and instability that now threatens the planet with its growth.  

The lesson from David is that design excellence transcends the object. Its message depends on context the way speech depends on place for gravity. In the case of modern architecture, its message will be one of secluded privilege until it can speak in the context of public benefit with the language of intensity.  

Intensity options are potential stones of knowledge for David’s sling. The target is a Goliath called precedent. The goal is adaptation. Architects and planners can rise to the occasion with others as David scans the horizon. This is where design excellence in the public interest can be found. Anything less will be a statue on a street corner.
AUTHOR NOTE: A policy goal is a sound byte without a leadership strategy. I suggested a strategic planning agenda in “Replacing Density”. For those who wish to read more, please see the detailed companion essays entitled, “Context, Capacity and Intensity” and “Parking Variances Offer a Glimpse into the Future”.

Wednesday, January 25, 2012

Parking Variances Offer a Glimpse into the Future

Parking variance requests indicate the need for more informed development capacity evaluation and design regulation. The improved platform is needed to provide leadership for more consistent and sustainable design excellence throughout a limited Built Domain.  

If an owner knows that he wants to construct a 30,000 sq ft. building with a parking lot and a parking requirement of one space for every 250 sq. ft. of gross building area (a250), the Planning Forecast Panel in Table 1 predicts rows of options related to the building height alternatives (f) listed in its left hand column.1 If we look across from the 3 floor option, the buildable acres column (BAC) in Table 1 tells us that he would need 1.987 acres based on the values entered in the Design Specification Template above. For the sake of this example, he owns 1.5 buildable acres and a quick scan down the BAC column tells us that even a 15 story building would require 1.713 acres. Obviously, some design adjustments are needed. Unfortunately, the (s), (a) and (S) values in the Design Specification Template, and the (f3) value in the Planning Forecast Panel, represent zoning ordinance requirements for this example; and at least one variance is needed to reduce the BAC required.

The arrows in Table 1 point to zoning requirements that will be discussed as variance options. Decisions lead to variance requests that are evaluated by a public Board of Zoning Appeal. Unfortunately, its decisions can be arbitrary because the logic for these regulations is poorly documented. This makes the regulation suspect and decision a matter of opinion among appointed residents. It’s no wonder we have sprawl, but let me finish this example by discussing the variance options in play before commenting further.

Table 1: Buildable Acre Requirements Based on a Given Gross Building Area Objective and a Template of Design Specification Values

Option 1: If the owner tested a parking variance from a250 to a355 in Table 1 while all other values remained constant, the BAC column in the Planning Forecast Panel would forecast the land area needed as 1.501 acres for a 3 story building.

Option 2: If the owner tested a project open space variance from 30% to 8.3% (S.3 to S.083) in Table 1 while all other values remained constant, the BAC column in Table 1 would again forecast the land area needed as 1.501 acres for a 3 story building.

Option 3: If the owner tested a reduction in the parking lot area provided per space from 400 sq. ft. per space (s400) to s282, the BAC column in Table 1 would forecast the land area needed as 1.502 acres for a 3 story building.


There are very practical problems with each of the variance options mentioned.

Option 1: Requesting a parking variance reduces the number of spaces provided, but the owner will argue that this is all that is needed in his particular case. This tailors the building to his need and ignores future owners. The city’s economic interest, however, depends on the building as a continuing source of public revenue that must maintains its attraction to future buyers.

Option 2: Most zoning ordinances don’t specify open space beyond setback requirements, and these can often be paved under the concept that a parking lot is open space. This is unfortunate because storm sewer sizes depend on runoff assumptions that depend on the relationship between open space and impervious development cover. A city that does not know these storm sewer runoff assumptions can easily permit excessive building cover and pavement that exceeds a property owner's share of capacity. In this theoretical example, a reduction to 8.3% open space might not even be feasible if the land has an irregular shape or other unusual characteristics that cannot accommodate the building and parking cover needed.

Option 3: An average surface parking lot area of 282 sq. ft. per space is not feasible when circulation aisles and turning islands are included in the calculation.


Option 3 is not realistic. Option 2, if possible, represents a building sitting in a parking lot. This is a solution that is familiar to all of us, but is vulnerable to decline, a threat to storm sewer capacity and a negative influence on neighborhood context and appearance.

Option 1 sacrifices public benefit for private gain. The parking lot may indeed be adequate for the owner’s purpose, but the building he occupies must continue to be useful after he leaves. If it is handicapped by inadequate parking, the community may suffer from a decline in attraction that can affect its economic stability over time.

A city is in the business of averages that protect its stability. Special exceptions defeat this purpose, and parking variances are a common attempt to over-develop land with exceptions that can easily threaten future value. The argument is often based on a claim of “hardship”, but the only hardship in this example is inadequate land area to accomplish the development objective. The claim that the parking requirement itself is a hardship based on the characteristics of a specific activity is a typical argument. It’s often successful because the requirement depends more on precedent than documented analysis. This leads to the claim that it is excessively restrictive in specific cases, but the law is written to protect the future with average values -- and the debate continues to search for proof that will always be an approximation.

Option 1 has just shown that the land owner must exceed the parking limit of a250 by 29.6% to reach his development capacity objective of 30,000 gross sq. ft. with a 3 story building. If a Board of Zoning and Planning approved this request, it would be similar to approving an 84.2 mile per hour speed in a 65 mile per hour zone, and most of us know there are limits to the latitude that should be taken.


The previous options have been based on data forecast from software model CG1B in the DCE software collection. Option 4 is based on forecast model CG1L and predicts the realistic gross building area capacity of the 1.5 acre land area just discussed. By locating the intersection of (f3) with the GBA column, you can see that the site has 23,658 gross sq. ft of building capacity when 3 floors are considered and 30% open space is specified. This increases to 24,723 sq. ft. if a 1 story height variance is granted to the (f4) row; and to 25,410 gross sq. ft. if a 2 story height variance is granted to the (f5) row, assuming all other zoning requirements are met. Neither variance comes close to the 30,000 sq. ft. objective.

If city storm sewer capacity in this area was originally designed for runoff from 30% impervious cover, 70% open space was anticipated. In this case, Option 4 would predict that 3 story gross building area capacity would decline to 10,139 sq. ft.

Option 4: The Realistic GBA Capacity of 1.5 Buildable Acres

Chart 1 has been created to plot the relationships just mentioned. Buildable area from 1 to 7 acres is arranged along the y-axis. Project open space options from 8.3% to 70% are arranged along the x-axis. Each line in the chart represents a building height option from 1 to 5 floors. All lines show that buildable acre predictions increase when unpaved project open space (S) increases along the x-axis and the gross building area objective remains constant at 30,000 sq. ft.. At any open space increment, a vertical line would intersect with all building height options and reveal the buildable acres required for each option. The results confirm what you would intuitively expect, but with mathematical accuracy.

Chart 1: The Effect of Building Height and Project Open Space Combinations on the Buildable Land Area Required


The relationship of building height to building cover produces building mass more commonly known as cubic area. Parking, loading and miscellaneous pavement combine with building cover to produce development cover, or impervious cover in civil engineering terms. The amount of gross building area that can be constructed per buildable acre is development capacity. The amount of open space provided on the same buildable area restricts development capacity by introducing context. The relationship of capacity to context is intensity. Intensity (INT) can be classified in the simplest terms by noting the number of building floors and percentage of total development cover planned or provided.

More specifically, intensity is the gross building area constructed in sq. ft. (GBA) per buildable acre involved (BAC), and is limited by the open space area introduced. The result is capacity and context. The capacity defined by design specification values shelters activity. The types and quantities of activity attracted determine economic stability.

Capacity can be measured on an intensity scale. A complete scale is represented by the design specification template in a forecast model. These values can be measured at existing locations. Other values can also be tested in a design specification template to forecast context, capacity and intensity options. This process of measurement, evaluation, decision and direction is an approach that can contribute to integrated open space and sustainable city design.

The lack of an adequate intensity measurement and forecasting system has obstructed our pursuit of knowledge. The obstruction has been removed with the DCE forecasting system. Its use can help us pursue knowledge that will determine our success in providing shelter for growing populations within a limited Built Domain that does not threaten its source of life – The Natural Domain.


A parking requirement is part of an intricate web of design specification values that combine to determine the context, capacity and intensity of an intended activity. When a design specification value represents a zoning requirement, its impact can be easily forecast with the DCE collection of forecast models. At this point it is an essential tool because we have limited confidence in specific zoning requirements. The result has been guesswork, a lack of public conviction, and doubt that leads to arbitrary variances, excessive intensity and sprawl.

The problem begins with the tools. City planning has had difficulty dealing with three dimensions, but cities are not only compromised by two-dimensional land use conflicts that require separation. They also suffer from an inadequate ability to forecast the consequences and opportunities of context, capacity and intensity options.  

The pressure of expanding populations and economic instability can easily lead us to sacrifice context for intensity. This increases shelter capacity and economic yield per acre, but it comes at the cost of context. We intuitively know that excessive intensity can threaten our quality of life, not to mention our sustainable future; but we haven’t been able to measure and evaluate the options. This has left use with sprawl while contemplating variance requests without an adequate frame of reference.  

In the end, our ability to evaluate variance requests will reveal the progress we have made toward a limited Built Domain that does not threaten its source, or quality, of life.

1Data predicted by forecast model CG1B in a software collection entitled Development Capacity Evaluation v.2. The collection is attached to its manual of explanation, Land Development Calculations, ed.2. The book and software have been written by Walter M. Hosack and published by the McGraw-Hill Companies, 2010.

Saturday, January 21, 2012


This is an updated version of “Where Does Sustainability Begin?”  

Sustainability begins with the recognition that we live on a planet with two opposing domains. We began in the first and now reside in the second. Linnaeus began to classify the Kingdoms of the Natural Domain around 1730, but overlooked The Built Domain and its four divisions: Shelter, Movement, Open Space and Life Support. It was a negligible factor during his time, but has grown into a competing artificial presence. This is a contest we cannot win in a universe that does not compromise with ignorance. It is why every acre of land is precious; why we must learn to live within limits; and why we must use each acre wisely as we attempt to shelter growing populations without consuming their source of life.

The consumption of land begins with the concept of property. I won’t even attempt to address this issue except to say that it has been the foundation of perpetual conflict, and that our current legal concepts will either appear anachronistic in time or become extinct. Adaptation is required and conscious adjustment is not inevitable, but I will leave its legal form for others to debate. My objective is to provide the tools needed to evaluate shelter options within sustainable limits defined by the science of others.

After Apollo 11, most will agree that the Earth is a finite resource protected by a thin film of atmosphere at risk; and that it exists within a universe defined as infinity. Therefore, the development capacity of land to provide shelter for growing populations becomes an issue of survival, since it is also a source of life that can be consumed. In other words, the built environment competes for land with the natural environment and survival hangs in the balance.

Land is used by four divisions within the built environment. The Shelter Division is served by the Movement, Open Space and Life Support Divisions. The relationship between building mass, pavement and open space within the buildable area of the Shelter Division is called intensity, which can be magnified by the surrounding intensity of its supporting divisions. Shelter intensity is expressed as the gross building area constructed per acre of buildable land available. Shelter capacity is found when gross building area is multiplied by the population anticipated per 1,000 square feet of building area forecast. The activities sheltered by building intensity combine to establish the social and economic characteristics of urban form.

Intensity options can be predicted with Development Capacity Evaluation software (DCE) based on the forecast model chosen and the values entered in its design specification template, and hundreds can be forecast in the time it takes to sketch one. The evaluation of these predictions can help us learn to use each acre wisely.

There has been no adequate definition of “over-development”, so the debate has wandered in a forest of detail and emotional confrontation that has only led to annexation, sprawl and blight. Debate has been limited by the language available, and DCE has been written to expand this vocabulary with accurate predictions of building capacity options. This may improve our ability to shelter growing populations within sustainable limits.

Intensity and context combine to create neighborhoods, districts, cities and regions. When the equations of intensity embedded in DCE software are linked to the mapping power of geographical information systems (GIS), the three-dimensional potential of urban form will emerge as options expressed in a visual and descriptive language. This can lead us toward life within limits that protect the health, safety and welfare of two worlds that now compete for survival.

Intensity options represent context choices. If we must learn to live within limits, then both intensity parameters and context design are critical to our health, safety and welfare. Within all divisions of the built environment, context is the form, function, appearance and arrangement of building mass, pavement and open space within the intensity parameters established. The most prominent parameters have been land use and transportation regulations, but our lack of ability to forecast intensity and correlate socio-economic benefit has produced a sprawling attempt to return to the farm.

Context is mute testimony to a great number of tactical design decisions made to achieve strategic leadership objectives. Strategy and tactics are lost without a goal, however. In this case, the goal is to create a Built Domain for mutual survival that does not threaten its source of life -- The Natural Domain. It is a worthy purpose for our continued presence if we can accept our stewardship responsibilities.

Author Note: Portions of this article were excerpted and edited from the second edition of my book, Land Development Calculations, and its attached forecasting software, Development Capacity Evaluation, v2.0 published by The McGraw-Hill Companies, 2010.

Tuesday, January 17, 2012

Context, Capacity & Intensity

***Please see my latest book, The Science of City Design: Architectural Algorithms for City Planning and Design Leadership, on in both e-book and paperback versions.***

City design and architecture adapt shelter, movement, open space and life support systems to The Natural Domain. From this perspective, design determines our ability to shelter growing populations within a limited Built Domain that does not threaten its source of life; and intensity is a label for the knowledge required. When this knowledge is accumulated, design recommendations will be defended with expanded explanations of benefit that include our physical, social, psychological and economic quality of life -- not to mention our sustainable future.
The following examples depend on a forecast model to predict architectural capacity and intensity from the data entered in its design specification template, but the impact implied by the intensity levels predicted is unknown. We simply know from experience that some of these predictions represent excessive intensity. We will have to rely on experience until research produces the conclusions we need to acquire knowledge. It’s an essential step into the sustainable future, because we cannot shelter growing populations within a limited Built Domain until we learn more about intensity; and we must learn in order to protect their source of life – The Natural Domain.

The open space of The Natural Domain is being consumed by the sprawl of The Built Domain. Agriculture is being sacrificed to sprawl within The Built Domain. Public open space is being sacrificed for private development. Project open space is being sacrificed to increase gross building area, and parking lot open space is being sacrificed to increase the number of parking spaces. The goal has been to increase the Shelter, Movement and Life Support capacity of a sprawling Built Domain by sacrificing its source and quality of life -- open space in both the Natural and Built Domains.   

Open space, however, will define the quality and opportunity for a sustainable future. This essay will discuss the potential of intensity options to preserve open space within and beyond a limited Built Domain, since The Natural Domain is open space that does not compromise with ignorance.  

A lack of intensity awareness has led to limited shelter options; over-development; excessive sprawl; consumption of agriculture; reduction of The Natural Domain; and pollution of the planet. These habits cannot continue indefinitely, because they discard a sustainable future for growing populations. 

Open space is the essential ingredient in a recipe that produces context. Recipe quantities produce a farm at one end of the context spectrum and a tenement at the other. This context spectrum is “intensity”, and we have labeled excess “overdevelopment”; but have been unable to accurately forecast or calibrate the physical, social, psychological and economic impact of intensity decisions within this spectrum of possibilities. In fact, only social reform could force us to recognize abuse; but it could not be measure the extent and was forced to adopt partial solutions as a consequence. Our city plans and zoning ordinances remain at this level of awareness today. 


In order to measure and forecast intensity I’ve had to create two specification outlines because residential and non-residential development involve substantially different characteristics. The forecast models within each family contain customized design specification templates that relate to specific design categories. Embedded equations process the area and height values entered to predict intensity options for the design category involved. These options are expressed as gross building area GBA potential. Each GBA forecast is divided by the number of buildable acres available to produce a measurement that defines an intensity option.  

I have discussed forecast models in many essays, and forecast model selection in “Improving the Argument for Architecture and City Design”. I won’t repeat myself here, but plan to use a forecast model to explain the effect open space has on context and capacity. The forecast model pertains to one land use family (C), one parking system (G), one design category (G1) and one design specification template. The gross land area (L) must be given in the model chosen. The forecast model is called CG1L and is illustrated by Table 1. It pertains to non-residential land uses with a grade parking lot around, but not under, the building when the gross land area is given.  

All quantities used in this essay were derived by entering values in the design specification template of CG1L. In its Planning Forecast Panel, four building floors has been emphasized to indicate that this building height has been adopted as a given to simplify this explanation. As you can see, I could have chosen any building height, or entered substitutes for the ones shown, but choosing more than one would have unduly complicated this effort. If you have read “Replacing Density”, you also know that anything over 5 building floors served by a grade parking lot produces a negligible increase in gross building area when open space is not reduced.  

Table 1: Forecast Model CG1L with Design Specification Values Entered in Blue


My objective is to explain the variable relationships between gross building area, parking area and open space that produce the context, capacity and intensity of shelter within cities. The design specification values that determine these relationships have not been previously distilled, and this lack of knowledge has compromised our ability to produce livable cities within sustainable limits.  Design specification values produce shelter context and capacity. The relationship between context and capacity becomes a measurable level of intensity when these values are understood, since they can be used to either define or predict the intensity of a design option being evaluated.  

Site Plan Hierarchy 

Figure 1 shows that gross land area is reduced by planned rights-of-way and paved easements to produce net land area NLA. The net land area is reduced by unbuildable land and existing conditions to produce buildable land area BLA. Buildable land is reduced by an open space percentage to leave core area CORE for building floor plan (“footprint”) and parking area. Open space in the net land area sets the stage for context and core area sets the stage for development capacity, or intensity. Unbuildable areas may represent amenity and visual appeal, but they are not part of open space context within the buildable land area that determines intensity.

It is possible that no open space and / or parking area will be provided, leaving a larger core area for the “building footprint”. It is also possible that the parking area will be placed under the building or underground. This approach can be used to either preserve open space or expand the potential core area at grade for a larger “building footprint”. Figure 1 serves to explain the site plan hierarchy involved when one remembers that any band can be zero, except for the building “footprint” area.

Figure 1: Site Plan Hierarchy

 Open Space 

When an open space percentage is held constant for a given land area and a CG1 design category is considered, gross building area is increased by increasing building height; but its “footprint” must be reduced to provide more land for the increased parking spaces required. Figure 2 is repeated from “Replacing Density” and is a series of pie charts simulating site plans that illustrate this relationship. You should notice in the pie charts that green remains constant while black becomes smaller and gray increases. 

Figure 2: Site Plans Reflecting Building Capacity Produced by Parking Lot, Building “Footprint” and Building Height Options -- when Open Space Remains Constant

Figure 3 is repeated from “The Limits of Shelter Capacity” and illustrates a design principle for parking lot design that is not apparent in the diagrams of Figure 2. The figure shows that increasing building height above 5 stories produces negligible increases in building capacity when the open space remains constant. A designer’s first reaction is to reduce the open space provided. This does not change the shape of the curve in Figure 3, but it does begin at a higher point on the y-axis.  

A designer’s second reaction is to reduce parking space and circulation aisle dimensions to reduce the gross parking lot area required. This increases the potential “footprint” area. His or her third reaction is to request a variance to the parking regulations. All three of these reactions, however, represent an attempt to increase the gross building area capacity of the site by modifying design specifications. A few examples should serve to illustrate how these design specifications affect the context, capacity and intensity of the cities we inhabit.  

Figure 3: Building Height Effect on Building Capacity When Parking Lot Area Varies and Open Space Remains Constant


Table 2 itemizes the constants and variable ranges used in the design specification templates of Table 1. They have been used to produce Charts 1, 2 and 3.  

Table 2: Variables and Constants Entered in Design Specification Template of Table 1

Chart 1 has been created by placing a series of open space options (S) on the x-axis and charting the gross building area decrease as S increases. The average parking area per space (s) remains constant at 350 sq ft. to examine the impact of parking regulation. Three lines represent three different parking requirements expressed as the gross building area permitted per parking space (a100, a250, a400). Chart 1 illustrates the combined impact of project open space allocation and parking regulation on gross building area capacity.

In other words, if you choose an open space increment S on the x-axis and project vertically from this location, the intersection with a diagonal line above indicates the gross building area potential of the combination. When the result is divided by the number of buildable acres involved, a level of intensity is calculated for the entire set of design specifications involved.

Chart 1: Parking Requirement Restrictions on Building Capacity When the Avg. Parking Lot Area per Space is Constant (s = 350 sq. ft.)

Chart 2 is identical to Chart 1 with one exception. The average parking lot area per space constant has been increased to 400 sq. ft. Chart 2 illustrates the impact of this increase on gross building area capacity. Such increases are considered for greater maneuverability and internal landscape improvement, but they reduce gross building area potential.

Chart 2: Parking Requirement Restrictions on Building Capacity When the Avg. Parking Lot Area per Space is Constant (s = 400 sq. ft.)

The gross building area GBA lines in Charts 1 and 2 become zero at 80% open space (S) because 5 gross acres was a given and 4 were calculated as remaining, or buildable, in the design specification template of Table 1. This is 80% of the gross land area; and when all is devoted to open space, there is no land remaining for building and parking. 

The three lines in Charts 1 and 2 represent 3 different parking requirements. They converge as the open space percentage (S) increases along the x-axis. These requirements are designated a100, a250, and a400. The number indicates the sq. ft. of building area permitted per parking space. The s350 and s400 values indicate the average sq. ft. of parking lot area provided per parking space. A higher (s) value indicates greater maneuverability and more landscape amenity within the parking lot.  

The GBA lines converge as open space increases and the core area remaining for development declines. Since open space is the raw material for context, Charts 1 and 2 document the relationship between an improvement in context and a reduction in capacity . This can lead to the elimination of context, over-development, and excessive intensity. 

Chart 3 has been created by placing open space options (S) on the x-axis and charting gross building area decline when the average parking area per space (s) increases from s350 to s400 and s450 sq ft. This illustrates the impact of greater parking lot area per space on gross building area capacity under various project open space alternatives. Increased average parking lot area per space is a design decision that can produce greater maneuverability and / or for parking lot landscaping. The parking requirement a200 is held constant to examine the design impact of greater parking lot area per space.

 Chart 3: Building Capacity When the Parking Requirement is Constant and the Avg. Area per Parking Space is a Variable

Chart 3 shows the same converging lines as Charts 1 and 2 but the spread is much narrower. This tells us that the average area provided per parking space has much less impact than the parking requirement itself. In other words, building capacity is less affected by the parking lot area provided per parking space (design) than it is by the building area permitted per parking space (regulation). Both reduce building capacity, however; and the combination is a funcamental design concern. 


Chart 4 shows that gross building area potential GBA increases 624% when the parking requirement declines from a50 to a450. This occurs when the open space variable (S) is held constant at 30%, the buildable land area is 4 acres, and the parking lot design provides an average of 350 average sq. ft. per parking space (s). Parking regulations from a50 to a450 are placed along the x-axis and the chart shows that gross building area (development capacity) increases by 624% as the parking requirement (a) declines.  

The (a) and (s) values can be confusing, so let me explain with Table 3. The table shows that a parking requirement permitting 50 building sq. ft. per parking space (a50) means that 20 spaces are required per 1,000 sq. ft. of gross building area. A parking requirement permitting 400 building sq. ft. per parking space means that only 2.5 spaces are required per 1,000 building sq. ft. In other words, a higher (a) value indicates a less restrictive parking requirement. A higher (s) value, however, means that fewer parking spaces can be provided per 1000 sq. ft. of surface area. For example, if the average area per space (s) is 400, 2.5 spaces can be provided per 1000 sq. ft. of area, but if (s) is 500, only 2 spaces can be provided per 1000 sq. ft. of area.  

Table 3: Explaining the (s) and (a) Values of Development Capacity Evaluation

Chart 4: The Impact of Parking Regulations on Gross Building Area Capacity

Chart 5 shows that gross building area potential GBA increases 100% when the average area per parking space declines from s750 to s350. This occurs when the project open space variable (S) is held constant at 30% of the buildable land area; and the parking requirement is held constant at a200, or 200 building sq. ft. permitted per parking space.  Average parking area per space is placed along the x-axis in a range from s750 to s350. Gross building area increments are located along the y-axis. The chart shows that development capacity increases by 100% as the average area per parking space (s) declines.

 Chart 5: The Impact of Parking Design on Gross Building Area Capacity 


In most cases, the number of parking spaces provided determines the gross building area that can be constructed. In some cases, parking is not required. In this example, a parking lot design category CG1 has been given. When it is, improved parking lot context means less capacity and a smaller gross building area when all other factors remain constant. 

When building context is improved with more project open space, the core area is reduced. This reduces the land available for building “footprint” and parking lot area. A smaller gross building area is the result when all other factors remain constant.  

When the average parking lot area per space increases to improve parking lot context and the core area is reduced by a project open space provision, gross building area potential is affected by both. This is evident when Chart 1 and Chart 2 are compared. They both contain three lines for the parking requirement range involved (a100 to a400), but Chart 1 plans for 350 sq. ft. per parking space (s350) and Chart 2 plans for s400. The impact of project context (S) and parking lot context (s) on building capacity (GBA) can be clearly seen by comparing the gross building area produced by the same (S) and (a) value intersection in both charts. 

The design implications should be clear. Project context (S) and parking context (s) combine to influence achievable shelter capacity, but maximum design eliminates context to increase capacity and intensity. We have always known this intuitively, but have not documented the design specification components and values in play. These interact to produce intensity in the cities we inhabit.

At the risk of over-simplifying the challenge before us, let me ask you to choose between Chart 1 and Chart 2. This choice determines parking lot design context and capacity. After choosing a chart, choose a project open space increment along the x-axis. This choice determines building context and capacity. The three lines above this increment represent the parking requirements a100, a250 and a400. This parking requirement choice is generally dictated by a zoning ordinance, but when you combine these decisions with the building height given, the result is a specification for shelter context and capacity, or intensity, that determines the gross building area potential per buildable acre involved. 

Table 1 illustrates one of 40 forecast models and contains the simplest example of a design specification template. The values entered represent context and capacity design decisions. Many potential decisions will produce excessive intensity. Our challenge is to rule them out with research while incorporating the remainder in city design for a limited Built Domain. This limited domain must provide shelter for growing populations, but not threaten their quality of life with excessive intensity. The challenge is enormous, because the limits of a Built Domain must also be designed by science to protect its source of life – The Natural Domain. 


We have not been able to efficiently forecast capacity, or understand the context and intensity represented, because we have not had an adequate and accurate research, measurement, forecasting, evaluation and decision-making system. I wrote Land Development Calculations and created Development Capacity Evaluation software1 to fill this gap.  

This essay has illustrated a few capacity and context options relating to the CG1 parking lot design category. The options discussed were forecast in Table 1 using the variables noted in Table 2. This produced many data tables since any change to a bold and blue value in Table 1 produces a new forecast, but the full set of data is not included for the sake of brevity. Table 1 has been included to illustrate the parent forecast model involved.  

This essay is meant to convey an underlying message. It is possible to pursue city design with architecture that protects a growing population’s physical, social, psychological and economic welfare within a limited Built Domain. It will not be possible, however, until we perceive the need and organize to achieve the goal with context research, intensity forecasting, development capacity evaluation and city design supported by political commitment, legal opinion and economic priority. 

1 Hosack, Walter M., Land Development Calculations, ed. 2, and attached forecasting software, Development Capacity Evaluation, v2.0 published by The McGraw-Hill Companies, 2010.

Wednesday, January 11, 2012

Questions About City Planning & Architecture

I received the following questions from Tara Imani, AIA in 2011 and remember asking myself similar questions over the years. I hope my answers will provide some insight. 

In the first question, the architect understands the planning staff available and is asking about responsibility for direction and achievement. Planners may sympathize with the question. Many have become administrators of a process to avoid decisions based on opinion that may threaten their employment. This simply preserves the legal precedent for sprawl, and is an expedient solution when opinion is not reinforced by research to repel challenge. 

Who is providing planning leadership? 

“WHO is responsible for zoning ordinances, tracking population growth, designing cities, urban and regional planning…?”  

There are many responsible in every State. It’s a question of what they’re accomplishing. (I’m not aware of anyone pursuing city design with an inter-disciplinary team on the scale, and with the tools, I’ve previously mentioned.) Right now we have land use separation goals written with a vision that hasn’t substantially changed since the beginning of the 20th century. It is based on our assumption, since the beginning of time, that land is an inexhaustible commodity for sale, conversion and improvement. My generation was the first to witness the limits of this assumption from the Moon. The old myth was destroyed but old habits remain in the history of law and the justification for combat. This has extended a pattern of sprawl that represents a threat, since it is consuming the face of the planet. It can only be met by a new level of awareness that is able to express competing arguments and implications with credibility. 

This leads to a fundamental question. How can we argue for land preservation when populations are growing and we provide shelter with sprawl? This question has led to the software vocabulary and language of Development Capacity Evaluation. It can predict hundreds of development capacity alternatives for a given land area in a fraction of the time it would take to draw one. This will improve city design debate because these predictions can be made within environmental limits. We have the professions responsible, but they need a new goal and new tools to predict strategic options with credibility. These are needed to support new 21st century tactics reinforced by a gigantic leap in the legal concept of property. This is a goal with leadership potential beyond a single profession, but it must be defined by a language that others can follow to produce the results expected. In my opinion, this means that the languages of planning, zoning, architecture, engineering, law, science and many others associated with our built environment need a common voice to lead shelter toward an essential relationship with our natural environment we have called “sustainable”. 

How can a sole practitioner make a difference? 

“My other concern is more general- how to make the quantum leap from a focus on projects to a focus on city and regional planning.  Now that you've answered these questions, I can better understand how this might overwhelm the ‘sole practitioner.’ “ 

A doctor uses the tools and knowledge developed by his profession. An architect must also rely on his profession. A sole practitioner cannot bridge the gap when it exists. This is not about a quantum leap from a project focus, since this is the essential role of any practitioner. It is about improving support for the effort. This involves professional goals, strategy, tools and knowledge that establish his or her credibility and social relevance within the community. It begins with a goal. My contention has been that the goal is city design within sustainable environmental limits that protect the quality of all life on Earth. Project practitioners will then design and build within the urban form and space outlined to protect a city’s physical, social and economic welfare. 

Social relevance and credibility will not be achieved by proclaiming that “design matters”. “Medicine matters” because health matters. It has become a credible statement after centuries of superstition. “Architecture matters” because shelter matters, but it’s a threat to the health of the planet. There is no escaping the fact that it is one of the five essential elements of survival, however. Many design and build shelter but the leadership question remains. How do we provide enough to serve growing populations with lifestyle options that respect sustainable environmental limits? The answer is critical because we must protect the life of the planet and its many inhabitants in order to protect our own? Most are only interested in design and construction for profit. Social relevance and credibility will be gained by professions that work to answer this question in the public interest.  

Architecture will have much to offer when it decides to build research and knowledge from the projects already stored in the archives of its many practitioners, since this is the raw material for context research, development capacity evaluation and leadership direction within the built environment. An national clearinghouse for context research is only a step away from practitioners with archive data that can improve the vocabulary of debate for all concerned with the language of Development Capacity Evaluation. 

How can we advance from tactical skill to strategic success? 

“…maybe it is asking too much to consider the architect's mindset orientation- fixed or growth, design-oriented or construction-oriented. Add to that, project-oriented or regional-development-oriented, and, well...architects have A LOT to think about these days!” 

My interpretation of this question may not be accurate, but the term “mind-set” attracted my attention. To me, a mind-set is an obstacle that resists new policies, goals, strategies and tactics. It’s a static, defensive strategy like the trench warfare of WWI. After years of stalemate and mounting casualties this strategy eventually adjusted with the invention of tanks.  

Everything mentioned in the question is a tactic. They become part of a strategy when the goal is clear. Design is a tactical effort to produce a strategy. Credibility has been lacking because the social relevance of its motive and goal are not clear, or accepted. The public recognizes the building code as a link between architecture and the public health, safety and welfare; but it has often been the subject of architectural criticism and disdain. This may have caused confusion since the public agrees with the goal of building regulation and would see objection as a threat to its interest. They simply ignore the strategic confusion produced by multiple organizations and tactical disagreements that prevent consolidation. This is another topic for another day, but is ripe with opportunity to make an architect more relevant to the community.  

In the case of architecture, I think tactics have received the overwhelming amount of attention without a clear sense of direction. This has produced an increasingly narrow focus that many have mentioned. It may represent an attempt to respond to the marketplace with old products and services while innovation from others reduces market share. 

The architectural mindset is on private practice, but a bigger market share will depend on a better demonstration of public benefit. There may be an opportunity when architecture recognizes its potential contribution to city design.  

In my opinion, the public interest has always been a secondary consideration in architecture. The client comes first for obvious reasons. Only a national organization can address the public interest while improving private practice and credibility. A practitioner must always meet expense, but the public value of advice he or she offers can be improved by answering one leadership question: What information, education and tools are required to convince the public that design matters? The public will be convinced when form, function and appearance are part of the knowledge needed to design cities that can shelter growing populations within sustainable environmental limits and structures. The ultimate goal is to preserve quality for all life on the planet, and it must be shared by many, but will always be represented by the cities and architecture created to reach each objective on the road to our strategic goal.  

In architecture, I’ve mentioned that the data for city design research resides in the archives of existing architectural practices, as well as on the street. Knowledge can be gained by dedicated measurement and evaluation of the design specification values represented. These values are the vocabulary of Development Capacity Evaluation. Healthy values defined through context analysis can become the language of city design for those who seek the knowledge to lead.  

Architecture is a part of the city design goal to shelter growing populations within sustainable environmental limits. The intent is to protect the planet’s ability to sustain quality for all life on Earth. The goal represents a public benefit of the highest order, but requires a new “mindset” and educational format to meet the challenge. Expanding this role to include a national focus on shared data and collective research for public benefit can increase market share for all who follow the path discovered. It is a concept that can lead architecture out of the trenches behind Development Capacity Evaluation, but only with the help of many other planners, engineers, scientists and related professionals who share the front line against impossible odds.  

Architecture has been accustomed to thinking of itself as an independent profession. The insularity of every profession appears to be a subconscious extension of our instinct to protect the survival of similar groups. The next level of awareness, however, will involve the survival of similar interests among all groups.  

One of these common interests is shelter without sprawl. Shelter matters, but a strategy to avoid sprawl begins with an effort to create the knowledge required. (Remember, structural engineering was not born. It began with the measurement and evaluation of relative strength among materials.) In the case of city design, it can begin with context measurement, evaluation and forecasting of tactical options using the vocabulary and tools of Development Capacity Evaluation. The language that evolves can define a strategy of urban form to contain sprawl, shelter populations, promote economic stability and provide social benefit. Architecture can then be deployed to achieve each objective on the road to a sustainable future within environmental limits.  

The benefit to public interest should be obvious. The benefit to architecture will evolve as it becomes a tactical extension of city design strategy for a sustainable future. This is the “mindset” for a new age of awareness whose symbol is a small blue planet and a thin film of atmosphere at risk from a concept we call “growth”. Without limits it will consume the land and pollute the environment within a universe of forces responding to a power that does not compromise with ignorance. 

NOTE: City design matters because we matter within the form and space we call cities, and because the planet beyond cannot be ignored. Architecture matters because its decisions represent the tactical execution of city design strategy. The goal is to achieve physical, social, economic and environmental success within sustainable limits that shelter growing populations and protect all life on Earth.  

Why is city planning separated from architecture? 

“As someone who considered majoring in City and Regional Planning, I have always seen the design of cities as intertwined and the basis for all architectural development. I was equally amazed to learn just recently - in a meeting with David Nicks, AIA of Transforming Architecture - that the only city in the U.S. to be designed by an architect is Lake Jackson, TX. I find that simply astonishing.” 

I haven’t thought about it in years, but planning involves public decisions and project regulation. Architecture involves private decisions and project design. This public-private relationship has a rocky history that began with building and zoning regulation. Architects are not in control of their design decisions. They can only make recommendations to owners who may not share their motivation and opinion. This relationship produced a threat to the public health, safety and welfare that had to be remedied with the historic regulations mentioned. The public-private relationship is now hindered by inadequate planning language and concepts that prevent the formation, evaluation and adoption of common design goals in the public interest. In its absence, planning regulation becomes one more architectural hurdle. When you consider that decisions are out of the hands of architects and planners in both sectors, goals are even more difficult to decipher and the public sector substitutes politics for leadership while sprawl continues. 

Why aren’t city planners architects? 

“I reminded Mr. Nicks that Pierre L'Enfant designed Washington, D.C. and he said, "Well, yeah, but he was not an architect!"  Well, what was Monsieur L'Enfant then?  A mere planner?  To me, a city planner MUST be an architect.  Am I missing something here?” 

Pierre Charles L’Enfant was a military engineer who was with Washington and Lafayette at Valley Forge. He became Captain of Engineers and had a thriving civil engineering firm in New York City after the war. He was responsible for the redesign of City Hall in New York City for the first Congress in Federal Hall, which I assume is how he came to be known as an architect. His plan for Washington, D.C. is actually a large subdivision plan that established a movement system and lot sizes. These have historically been prepared by civil engineers, but are only a piece of the puzzle that is city design. 

Your contention that a city planner must be an architect is a loyal position. It may stem from the fact that buildings are served by engineering systems; but shelter is only one of four divisions of the built environment. The only common pre-requisite for planners is cooperation, since the topic is vast. The skills required are diverse, and they can be in short supply. Buildings are projects. Cities are a process. They must have adequate leadership over generations. This is not the time frame of an architect in the private sector, or of an architect in the public sector, unless he or she is working as a planner. In this case, architectural skills can be of value to the total planning effort when they focus on the physical, social, economic and environmental decisions needed to pursue city design in the public interest. 

Is anyone working on the problems stated in your article? 

“After reading your article, I feel I've entered a parallel universe - one without the existence of a single urban planner, no city and regional planners, and no university programs teaching urban design.  

In other words, SURELY, SOMEONE else must be concerned and working on the problems you've stated in your article. Aren't they?” 

There are plenty of planners, designers and university programs, but we only see trees when walking in a forest. Sprawl is confusion turning in circles and searching for leadership. Resolution will depend on new concepts and tools. It’s hard to argue that our education, decisions and practice are leading us in the right direction. Residents guide their city’s evolution and opinion is the common currency. In this forest the most convincing argument wins, and the claim that design opinion should prevail has never had the credibility required for automatic acceptance. Any claim that planning education and practice have the answers must explain why sprawl continues.  

The first edition of my book and software were published 10 years ago. I’m not aware of anyone pursuing the issues mentioned with the software provided. I have suggested that our goal is to preserve the planet’s ecological ability to sustain all life on Earth. This means designing cities within geographic limits that shelter growing populations. I am not aware of any coordinated pursuit of this goal, but I will be the first to admit that I’m not an academic familiar with the work of others. 

Who should address the issue of sprawl? 

“So, who's responsibility IS IT?  The green people of the USGBC?  The good people of the AIA who decide to take on suburban sprawl?  Or who?  If you could design (or hire) the perfect "A" team to address this problem, who (profession-wise) would be on it?  A scientist, geologist, city planner, architect, civil engineer, neighborhood association leaders, Mr. Ed Mazria of the Architect 2030 challenge, urban planners, advocates against "suburban sprawl"… “ 

The shape of our cities has evolved from real estate law. In fact, planning and zoning began when the law realized it had to protect the public health, safety and welfare from conflicting land use activities, excessive density and inferior construction. Land use separation has only been a partial success, however, because it has inadequately addressed the three dimensions of city design. Two-dimensional land use activities are sheltered by three-dimensional urban form. The intensity of urban form defines development capacity, or gross building area per buildable acre. Land use plans have been unable to forecast the gross building area that will emerge. This means they have been unable to accurately forecast anything that is a function of gross building area, such as population, intensity and revenue. This in turn has left their land use plans floating without a financial lifejacket while drifting toward sprawl and blight. You may be surprised that no one has done more, but sprawl represents our best effort to date because the law has not had adequate tools to precisely address the future of three-dimensional urban form. 

Imagine an interactive three-dimensional computer graphic that displays the urban form and space of a city. The graphic correlates this form to the activities sheltered and the average revenue produced per acre. Next, imagine that you could adjust this form and space one project at a time by changing the variables in a development capacity equation. The form would adjust and you could read the change in average revenue per acre implied -- while comparing it to the city’s average expense per acre. Then imagine that you could design a city’s entire urban form with these variables to produce the development capacity, open space and revenue potential needed to support the shared services required over time. Imagine that you could also evaluate another option, or a development proposal, with the same model. This is not that far-fetched when you are able to predict the development capacity of any land area with mathematical values assigned to the design specification template of a forecast model representing a building design category. These calculations can be converted to three-dimensional volumes on a screen that indicates building mass and its relationship to space. When this is applied to an entire city, the graphic represents a schematic outline of urban form we call a city, and can be adjusted by changing any set of design specification values associated with an individual project area of any size.  

The picture just painted represents the city design of urban form with the credibility to convince others of the direction needed. Finally, imagine that this graphic model has pre-defined geographic limits; and that all urban form adjustments must take place within these limits to protect and preserve the environment beyond. In other words, these ecological boundaries express the goal of life within limits. City design of urban form outlines the strategy needed. Architecture, engineering and science make the tactical decisions required to build the shelter component of our sustainable goal. At this point, architecture will define urban form with the detail required to build results that reflect the knowledge gained. 

A lot of people talk about sprawl, but the relationship of property rights to growth limits has been an obstacle. Jefferson’s declaration of property rights was written when the population was limited and the continent appeared infinite. Since architecture and planning were some of his many skills however, I believe he would participate in a clarification that responds to growth he could not imagine and had no reason to fear. 

Jefferson was concerned about whose rights should prevail – the divine right of King George III or the rights of the people. Even he did not realize that the rights of the planet prevail. At that time he was busy with an inventory and classification of the resources he imagined. Less than 200 years have passed since his death and we are still busy with the inventory. We have counted enough, however, to realize that extinction has occurred. We may not be able to prove the cause, but must listen to instinct that only wisdom can hear. 

Sprawl represents a search for revenue to support city services. It is not simply a response to population growth. A developer responds to growth with shelter in the pursuit of profit. Cities react to these proposals and respond to the prospect of new revenue. They assume that their land use plan is a satisfactory economic model because they have no other option. Unfortunately, cities simply do not understand the balance of land use activity and urban form required to supply adequate revenue over an extended period of time. This has led most to approve development applications that represent new money, but long term expense that will exceed their average revenue over time.  

In answer to your question, cities should address sprawl, or inadequate land use allocation for those with no room to expand, by addressing the development capacity and economic yield issue I called the city design of urban form. The law simply cannot proceed without this informed direction. (I’ll avoid listing team members and functions.) This requires thinking of the city in three dimensions, since economic yield is a function of the activities and gross building area constructed per acre of land available. This can be overdone however, and open space must enter the equation to offset intensity and offer lifestyle options. Development Capacity Evaluation software has been created to forecast gross building area potential based on the model selected and the variables entered in its design specification template. When an option is calculated, it is a short step to forecast the population, income, revenue, construction cost and return on investment implied.  

I have not described a traditional professional service. It depends on a city with real estate data recorded on a geographic information system; revenue information it is willing to share; expense information it is willing to assemble; a staff willing to enter additional correlation data for mapping; and a government willing to share this information with the public. Development Capacity Evaluation and city design can proceed when this foundation is in place. Anything less will lack the credibility needed to justify urban form options and city design recommendations that can be pursued over time. This is an effort that will benefit from the contributions of many, including architects, who not only design but investigate the physical, social, psychological and economic implications of their work with context research. 

NOTE: “City design” as used in this context does not mean city planning or urban design. City planning is still primarily concerned with two-dimensional land use relationships, and its design standards are lost in detail that produce arbitrary results without a coherent goal or strategy. Urban design addresses three-dimensional environments in limited project areas with correspondingly limited goals and strategy.  

Is my neighborhood at risk? 

“I happen to live in a suburban neighborhood- and it is NOT dying!!” 

I am not familiar with your city and neighborhood but suggest you read, “The City is a Farm” on my blog before reaching any conclusions. Residents are simply not familiar with municipal income sources and expense requirements over time; and rarely have annual state of the city messages that help with their assessment for whatever reason. Revenue and expense correlation with development capacity and urban form, however, is an absolutely essential foundation for city design that has the credibility to lead the tactics of economic development, architecture and engineering. The correlation of development capacity with other affected urban functions is only limited by the imagination, and represents the future potential of Development Capacity Evaluation.