humanCITY

Architects typically think of density in terms of “Dwelling Units per Acre” on specific sites, inside the property line. Some disadvantages of this metric are that a “unit” can be a studio, or a 5 bedroom dwelling, and factors such as public ROW (Right of Way), percentage of parkland, etc. are ignored.

PSM, or People per Square Mile, is a better metric for setting a district density goals. PSM is readily available for existing urban areas. However to convert from the area of residential in a plan to PSM assumptions need to be made. 

The assumptions used:
0.33 of urban land has a residential use.
2.5 people per dwelling

The Utopian TOD is imagined as having 9 blocks with the central block a park, so generous open space can be part of very high density design.

Comercial space, to achieve a “jobs/housing” balance, is provided as well at a 25% ratio to total square footage.

Conspicuously parking is not included in the theoretical design. It could be located underground, or outside the district. The amount required would be reduced by the use of car sharing as well as the inherent pedestrian and cycling friendliness of location efficiency.

Transit Oriented Developments, districts planned in walking distance of high capacity public transit, such as BART, could benefit from being planned to a People per Square Mile (psm) goal.

Utopian TOD - 200 x 200 (site area: 40,000 SF)

Cities

Berlin – 350 x 900 (315,000 SF)

Buenos Aires – 375 x 375 (140,625 SF)

Chicago – 330 x 660 (217,800 SF)

Glasgow – 225 x 300 (67,500 SF)

Helsinki – 400 x 500 (200,000 SF)

Houston – 300 x 300 (90,000 SF)

Johannesburg – 225 x 225 (50,625 SF)

Kansas City – 250 x 400 (100,000 SF)

London – 120 x 300 (36,000 SF)

Madrid – 275 x 500 (137,500 SF)

Melbourne – 350 x 700 (245,000 SF)

New York City – 250 x 500 (125,000 SF)

Omsk – 300 x 700 (210,000 SF)

Philadelphia – 125x 425 (53,125 SF)

Phoenix - 275 x 600 (165,000 SF)

Portland - 200 x 200 (40,000 SF)

Riyadh – 400 x 450 (180,000 SF)

Seattle – 250 x 250 (62,500 SF)

Taipei City – 150 x 350 (52,500 SF)

Tokyo – 300 x 500 (150,000 SF)

Toronto – 250 x 300 (75,000 SF)

Winnipeg – 275 x 500 (137,500 SF)

San Francisco Neighborhoods

Bernal Heights – 300 x 650 (195,000 SF)

Castro – 300 x 650 (195,000 SF)

Excelsior – 200 x 650 (130,000 SF)

Financial District – 300 x 300 (90,000 SF)

Hayes Valley – 300 x 400 (120,000 SF)

Mission – 200 x 500 (100,000 SF)

North Beach – 300 x 400 (120,000 SF)

Pacific Heights – 300 x 400 (120,000 SF)

Potrero Hill – 200 x 500 (100,000 SF)

SOMA – 800 x 150 (120,000 SF)

Union Square – 400 x 250 (100,000 SF)

Western Addition – 300 x 400 (120,000 SF)