Equation 1: INT = TDA / S
Table 1 presents the potential range of intensity options within our built environment using Equation 1, and is also repeated from “The Nature of Intensity”. These calculations have nothing to do with form, function and appearance, which is similar to the fact that Archimedes’ shape, anatomy and appearance had nothing to do with his discovery of mass as he displaced water in an over-filled tub. Equation 1 also has nothing to do with the activities inside a building. From a shelter intensity standpoint, all buildings and pavement are the same. The same intensity value will produce the same open space displacement. The activities sheltered within will produce additional levels of traffic and utility demand. Since movement, public open space and life support systems serve shelter however, shelter intensity protects activity that magnifies intensity in any neighborhood. In other words, urban form is an expression of physical intensity that is magnified by social activity, and supported by economic yield with corresponding psychological implications.
We have not adequately defined intensity to efficiently use the development capacity of land within sustainable limits. Do not leap to the conclusion that I’m proposing a universal lifestyle of high intensity to accommodate population growth, however. I’m proposing that we must understand intensity before we can offer a range of options to shelter growth within natural limits. This means that we must be able to understand development capacity and intensity before growth takes away our options.
TABLE 1
DEVELOPMENT INTENSITY TABLE
| NOTE: | | | | | | | | | | |
| BLA= | buildable land area | | | | | |||||
| S= | project open space | | | | | | | | ||
| GBA= | total building area including all floors | | | |||||||
| BCA= | total building cover area (footprint) | |||||||||
| TPC= | total pavement cover | | | |||||||
| TDC= | development cover area | | | | | | | | ||
| TDA= | total development area | | | | | | | | ||
| TDC= | BCA + TPC | | | | | | | | | |
| TDA= | TBA + TPC | | | | | | | | | |
| | | | | TDC and S as fraction of BLA | | | ||||
| S | 0.9 | 0.8 | 0.7 | 0.6 | 0.5 | 0.4 | 0.3 | 0.2 | 0.1 | 0.001 |
| TDC | 0.1 | 0.2 | 0.3 | 0.4 | 0.5 | 0.6 | 0.7 | 0.8 | 0.9 | 0.999 |
| | | | | | | | | | | |
| TDA or GBA as | | | INTENSITY as a multiple of BLA | | | | | |||
| multiple | | | NOTE: Values above stair step only apply to GBA intensity since TDA + S must be >= 1 | |||||||
| of BLA | | | GBA + S can be < 1 since total pavement cover TPC is not included | |||||||
| | | | | | | | | | | |
| 0.10 | 0.11 | 0.13 | 0.14 | 0.17 | 0.20 | 0.25 | 0.33 | 0.50 | 1.0 | 100 |
| 0.20 | 0.22 | 0.25 | 0.29 | 0.33 | 0.40 | 0.50 | 0.67 | 1.00 | 2.0 | 200 |
| 0.30 | 0.33 | 0.38 | 0.43 | 0.50 | 0.60 | 0.75 | 1.00 | 1.50 | 3.0 | 300 |
| 0.40 | 0.44 | 0.50 | 0.57 | 0.67 | 0.80 | 1.00 | 1.33 | 2.00 | 4.0 | 400 |
| 0.50 | 0.56 | 0.63 | 0.71 | 0.83 | 1.00 | 1.25 | 1.67 | 2.50 | 5.0 | 500 |
| 0.60 | 0.67 | 0.75 | 0.86 | 1.00 | 1.20 | 1.50 | 2.00 | 3.00 | 6.0 | 600 |
| 0.70 | 0.78 | 0.88 | 1.00 | 1.17 | 1.40 | 1.75 | 2.33 | 3.50 | 7.0 | 700 |
| 0.80 | 0.89 | 1.00 | 1.14 | 1.33 | 1.60 | 2.00 | 2.67 | 4.00 | 8.0 | 800 |
| 0.90 | 1.00 | 1.13 | 1.29 | 1.50 | 1.80 | 2.25 | 3.00 | 4.50 | 9.00 | 900 |
| 1.00 | 1.11 | 1.25 | 1.43 | 1.67 | 2.00 | 2.50 | 3.33 | 5.00 | 10.0 | 1,000 |
| 1.25 | 1.39 | 1.56 | 1.79 | 2.08 | 2.50 | 3.13 | 4.17 | 6.25 | 12.5 | 1,250 |
| 1.50 | 1.67 | 1.88 | 2.14 | 2.50 | 3.00 | 3.75 | 5.00 | 7.50 | 15.0 | 1,500 |
| 1.60 | 1.78 | 2.00 | 2.29 | 2.67 | 3.20 | 4.00 | 5.33 | 8.00 | 16.0 | 1,600 |
| 1.70 | 1.89 | 2.13 | 2.43 | 2.83 | 3.40 | 4.25 | 5.67 | 8.50 | 17.0 | 1,700 |
| 1.75 | 1.94 | 2.19 | 2.50 | 2.92 | 3.50 | 4.38 | 5.83 | 8.75 | 17.5 | 1,750 |
| 2.00 | 2.22 | 2.50 | 2.86 | 3.33 | 4.00 | 5.00 | 6.67 | 10.00 | 20.0 | 2,000 |
| 3.00 | 3.33 | 3.75 | 4.29 | 5.00 | 6.00 | 7.50 | 10.00 | 15.00 | 30.0 | 3,000 |
| 4.00 | 4.44 | 5.00 | 5.71 | 6.67 | 8.00 | 10.00 | 13.33 | 20.00 | 40.0 | 4,000 |
| 5.00 | 5.56 | 6.25 | 7.14 | 8.33 | 10.00 | 12.50 | 16.67 | 25.00 | 50.0 | 5,000 |
| 6.00 | 6.67 | 7.50 | 8.57 | 10.00 | 12.00 | 15.00 | 20.00 | 30.00 | 60.0 | 6,000 |
| 7.00 | 7.78 | 8.75 | 10.00 | 11.67 | 14.00 | 17.50 | 23.33 | 35.00 | 70.0 | 7,000 |
| 8.00 | 8.89 | 10.00 | 11.43 | 13.33 | 16.00 | 20.00 | 26.67 | 40.00 | 80.0 | 8,000 |
| 9.00 | 10.00 | 11.25 | 12.86 | 15.00 | 18.00 | 22.50 | 30.00 | 45.00 | 90.0 | 9,000 |
| 10.00 | 11.11 | 12.50 | 14.29 | 16.67 | 20.00 | 25.00 | 33.33 | 50.00 | 100.0 | 10,000 |
| 50.00 | 55.56 | 62.50 | 71.43 | 83.33 | 100.00 | 125.00 | 166.67 | 250.00 | 500.0 | 50,000 |
| 100.00 | 111.11 | 125.00 | 142.86 | 166.67 | 200.00 | 250.00 | 333.33 | 500.00 | 1,000.0 | 100,000 |
| 200.00 | 222.22 | 250.00 | 285.71 | 333.33 | 400.00 | 500.00 | 666.67 | 1,000.00 | 2,000.0 | 200,000 |
| 400.00 | 444.44 | 500.00 | 571.43 | 666.67 | 800.00 | 1,000.00 | 1,333.33 | 2,000.00 | 4,000.0 | 400,000 |
| 500.00 | 555.56 | 625.00 | 714.29 | 833.33 | 1,000.00 | 1,250.00 | 1,666.67 | 2,500.00 | 5,000.0 | 500,000 |
| | | | | | | | | | | |
The RG1L forecast model in Table 2 makes the case that all design specifications produce a discrete level of intensity, and that the combination of design specifications and intensity benchmarks can become a leadership language for city design and architecture. The RG1 design category applies to multi-family residential buildings using grade parking lots around, but not under, the building. The suffix L means that gross land area must be given. The design specification template for RG1L is quite different from the CG1L template used in “The Nature of Intensity”, since it includes characteristics that make multi-family residential buildings a unique design category. The design specification values entered, however, produce forecasts that predict the relationship of building mass and pavement to open space. The component areas of this relationship are predicted in The Planning Forecast Table. Total development area TDA is simply the sum of these pieces for each building height option noted. In other words, TDA = GBA+PLA+RDA+LDA+MSP, or total development area equals the sum of gross building area, parking area, public right-of-way area, loading area and miscellaneous pavement area for each building height option (f) noted. The relationship between the TDA forecast and the open space S specified in the design specification template determines the intensity INT forecast for each building height option (f).
The design specification template in forecast model RG1L is quite involved because of its dwelling unit mix options; and it should be clear that a nearly infinite number of options is possible, since a change in one or more design specification values produces a new forecast. All of these options, however, will produce levels of intensity that fall within the universal table of intensity presented in Table 1. The specific INT values represented by this example are included in the right-hand column of Table 2.
TABLE 2
MULTI-FAMILY REIDENTIAL INTENSITY: AGG = 1,000
| DESIGN SPECIFICATION | | ||||||||||
| | | | | | | | | | | | |
| Given: | | | | 4.000 | | 174,240 | SF | ||||
| Public/ private right-of-way & paved easements | | 0.000 | W as fraction of GLA | 0 | SF | ||||||
| | | | 4.000 | NLA in acres | | 174,240 | SF | ||||
| Facilities and features to remain as fraction of GLA | | 0.000 | | 0 | SF | ||||||
| | X= | 0.000 | fraction of GLA | | 0 | SF | |||||
| Buildable Land Area Remaining | BLA= | 4.000 | acres | | 174,240 | SF | |||||
| Est. gross pkg. lot area per pkg. space in SF | s = | 350 | ENTER ZERO IF NO PARKING REQUIRED | | |||||||
| Parking lot spaces planned or required per dwelling unit | u= | 1.5 | ENTER ZERO IF NO PARKING REQUIRED | | |||||||
| Garage parking spaces planned or required per dwelling unit | Gn= | 0 | ENTER ZERO IF NO PARKING REQUIRED | | |||||||
| Gross building area per garage space | Ga= | 0 | ENTER ZERO IF NO PARKING REQUIRED | | |||||||
| No. of loading spaces | l = | 0 | | | | | |||||
| Gross area per loading space | b = | 0 |
| | 0 | SF | |||||
| Project Open Space as fraction of BLA | S= | 0.300 | | | 52,272 | SF | |||||
| Private Driveways as fraction of BLA | R= | 0.030 | | | 5,227 | SF | |||||
| Misc. Pavement as fraction of BLA | M= | 0.020 | | | 3,485 | SF | |||||
| Loading area as fraction of BLA | L= | 0.000 | 0 | R+M+L= | 8,712 | SF | |||||
| Total Site Support Areas as a fraction of BLA | Su= | 0.350 | | | 60,984 | SF | |||||
| Core development area as fraction of BLA | C= | 0.650 | C=Su must = 1 | | 113,256 | SF | |||||
| Building efficiency as percentage of GBA | Be= | 0.850 | must have a value >0 entered | | | ||||||
| | Bldg. support as fraction of GBA | Bu= | 0.150 | Be + Bu must = 1 | | | | ||||
| Dwelling Unit Mix Table: | NOTE: The Dwelling Unit Mix table requires that (Be) above contain a value greater than zero. | ||||||||||
| DU | | GDA | | CDA=GDA/Be | | MIX | | | PDA = (CDA)MIX | | |
| dwelling unit type | | gross du area | | comprehensive du area - unless override, fill in (Be) | | du mix | | | Pro-rated du area | | |
| EFF | | 350 | | 412 | | 0% | | | 0 | | |
| 1 BR | | 500 | | 588 | | 30% | | | 176 | | |
| 2 BR | | 1,000 | | 1,176 | | 70% | | | 824 | | |
| 3 BR | | 1,200 | | 1,412 | | 0% | | | 0 | | |
| 4 BR | | 1,400 | | 1,647 | | 0% | | | 0 | | |
| | Aggregate Avg. Dwelling Unit Area | (AGG) = | 1,000 | | |||||||
| | GBA sf per parking space | a= | 667 | | |||||||
| PLANNING FORECAST | Enter zero in the adjacent box unless you wish to override the AGG value calculated above | 0 | | ||||||||
| no. of floors | | | density per | dwelling units | pkg. lot spaces | parking lot area | gross bldg area | footprint | total | intensity | |
| FLR | | CORE | dBA | NDU | NPS | PLA | GBA | BCA | TDA | INT | |
| | | min. area for BCG & PLA | buildable acre | | | | no garages | no garages | dev. area | TDA / S | |
| 1.00 | | 113,256 | 18.57 | 74.3 | 111.4 | 38,990 | 74,266 | 74,266 | 121,968 | 2.33 | |
| 2.00 | | | 27.62 | 110.5 | 165.7 | 58,009 | 110,494 | 55,247 | 177,215 | 3.39 | |
| 3.00 | | | 32.99 | 131.9 | 197.9 | 69,273 | 131,949 | 43,983 | 209,934 | 4.02 | |
| 4.00 | | NOTE: | 36.53 | 146.1 | 219.2 | 76,722 | 146,137 | 36,534 | 231,571 | 4.43 | |
| 5.00 | | Be aware | 39.05 | 156.2 | 234.3 | 82,013 | 156,215 | 31,243 | 246,940 | 4.72 | |
| 6.00 | | when BCA | 40.94 | 163.7 | 245.6 | 85,965 | 163,744 | 27,291 | 258,421 | 4.94 | |
| 7.00 | | becomes too | 42.40 | 169.6 | 254.4 | 89,030 | 169,581 | 24,226 | 267,323 | 5.11 | |
| 8.00 | | small to be | 43.56 | 174.2 | 261.4 | 91,476 | 174,240 | 21,780 | 274,428 | 5.25 | |
| 9.00 | | feasible | 44.51 | 178.0 | 267.1 | 93,473 | 178,044 | 19,783 | 280,230 | 5.36 | |
| 10.00 | | | 45.30 | 181.2 | 271.8 | 95,135 | 181,210 | 18,121 | 285,057 | 5.45 | |
| 11.00 | | | 45.97 | 183.9 | 275.8 | 96,539 | 183,884 | 16,717 | 289,136 | 5.53 | |
| 12.00 | | | 46.54 | 186.2 | 279.3 | 97,741 | 186,174 | 15,515 | 292,628 | 5.60 | |
| 13.00 | | | 47.04 | 188.2 | 282.2 | 98,782 | 188,157 | 14,474 | 295,651 | 5.66 | |
| 14.00 | | | 47.47 | 189.9 | 284.8 | 99,692 | 189,890 | 13,564 | 298,295 | 5.71 | |
| | | | | | | | | | | | |
NOTE: When open space and parking requirements remain constant, development capacity declines rapidly above 5 floors.
The point is that buildings shelter a wide range of activities; but their appearance, construction and purpose have confused the issue of sprawl and sustainability. They all provide shelter and produce levels of intensity that reflect the design specification values chosen. These intensity options displace open space. Forecasts define the options available to shelter growing populations, but not all are desirable. Existing context evaluation will provide information for comparison and evaluation. Decisions will be defined with design specifications and intensity measurements that have strategic leadership potential. The architecture that emerges will respond to the policy decisions adopted.
Growing populations ensure that a sprawling pattern of random construction on plentiful land cannot continue. We are expected to take the issue seriously as stewards who have not yet recognized their planning responsibility. Cities are simply architecture on a grand scale. If architectural design does not express this new level of land use awareness, then we will not be able to lead cities toward a sustainable future – no matter how environmentally conscious and energy efficient we become. In this scenario, sprawl consumes the land while public health and safety exacerbate the problem and increase a decline in our quality of life.
Table 2 predicts physical intensity as a foundation for social and economic activity based on the design specification values entered. I won’t belabor the point since I hope I have made these relationships clear, but the underling message is that we can predict intensity before we build, which means that leaders can plan and design shelter options for the activities of growing populations within sustainable limits, but we need the commitment, research and authority to begin.
AUTHOR NOTE: The forecast models displayed are part of a software collection entitled, “Development Capacity Evaluation” that is included with the book, Land Development Calculations, ed. 2, McGraw-Hill, 2010. More information about the book and software are included in the “About Me” section of this blog.
