sustainable development off on the grid frames values...sustainable development off on the grid •...
TRANSCRIPT
Sustainable Development
Off ON the GRID • Frames for thinking about sustainable development
• Values of historic patterns of building and development
• Threats to historic patterns of building and development
• Policies to conserve our existing patterns of development
Presentation Outline
RMLUI 2009 ConferenceJim Lindberg
Frame: Technology will solve it
www.PreservationNation.org/green
Sources of CO-2 Emissions
Buildings 48%
percentage of emissions
All Other Carbon Emissions in the World 90%
U.S. CO-2 Emissions
World CO-2 emissions
Transport 27% Other 25%
U.S.Bldgs 10%
Source: Architecture 2030, American Institute of Architects
Projected Building TrendsSq
uare
feet
Existing Buildings
2005 2030
100 B
200 B
300 B
400 B
Demo82
Remodel150
New230
300 B
427 B
Rehab ?82
New ?148
Source: Brookings Institution
Frame: Technology will solve it
Frame: Technology is the solution
“gadget green”
“the assumption of consumption”
Frame: Technology is the solution
.
Frame: back to nature
Frame: back to nature
How did I get here?
Frame: back to nature
Frame: back to nature
Frame: conserving what we have
“When we throw awayone two-story, 125 x 50 ft Main Street building…
We are un-doing the environmental benefits of recycling 1,345,000aluminum cans.”
Donovan Rypkema
Demolition Waste
The greenest building is…one that already exists
Existing Historic
New “green” construction
Life - Cycle Energy Use: New vs. Historic
dem
30 yr
Energy Use
15 yr
Assumptions:
• Both houses are same size
• New house uses half of annual energy used by existing
Life-cycle use remains lessEfficientHistoric
BIGNEW
“GREEN”
construction
Life-Cycle Energy Use: New vs. Historic
Annual Energy Use
Annual Energy Use
dem
Energy Use
25 yr
Assumptions:
• New house TWICE as large as existing
• Old house upgraded to be more energy efficient
upgr
Value: Traditional Building Practice
Value: Traditional Building Practice
• site location and orientation to maximize light and passive solar
• planting of trees to protect from sun/wind
• natural ventilation from operable windows, transoms and high ceilings
• eaves, shutters, porches and awnings
• courtyards, window wells, skylights, large exterior windows to maximize natural light
• use of masonry to create thermal mass to modulate heating and cooling
• human proportions and scale and efficient use of space
Pre-1920
40,000
50,000
60,000
70,000
80,000
90,000
100,000
Average annual energy consumption(Btu/sf commercial buildings, non-malls)
1920-1945
1946-1959
1960-1969
1970-1979
1980-1989
1990-1999
2000-2003
Source: General Services Admin
Value:Adaptability
LEED Silver Certified Federal Office Building, Ogden, UT
LEED Certified Senior Housihg, Salina, KS
LEED certified projects
Rehab Tax Credit
certified projects
5,000
10,000
15,000
20,000
25,000
30,000
35,000
3,000
34,000
LEED and Rehab Tax Credit projects completed in U.S.
?
CombinedTax Credit
& LEED projects
< 100
Cincinnati
Value: Pedestrian scale
Value: Pedestrian scale
Value: Public investments
Value: Public investments
Value: Mixed use development
Value: Transit-oriented development
1900
Transit Ridership: 1900 - 2007
1950
1950
1930 1960 1990 2020
Trip
s pe
r yea
r
30 B
10 B
20 B
Source: US Census
1946
1972
Threats to historic buildings and patterns of development
Boston, MA
Denver, CO
Teardown: the practice of purchasing an older house, demolishing it, and replacing it with a much larger structure
Teardowns in over 400 Communities
983 sf
1950
2,521 sf
2007
• Average household size decreased 22%
• Average area per person increased 188% to 840 sf
• Number of 1-person households up from 9% to 27%
• Average single family lot = 16,864 square feet in 2007
Changes in House Size: 1950 - 2007
Source: US Census
Many neighborhoods are “over-zoned”
Policies to conserve historic neighborhoods and communities
Percentage of structures protected by landmark ordinance in major US cities
Total number of structures in city and % protected
Chicago 500,000 1% landmarked
New York 1,000,000
Denver
2%
240,000 4%
Chicago
A Form Based Code (FBC) moves the emphasis of zoning from use to form
FBC’s are based on an analysis of existing context
Policies: Form Based Codes
Type A1
Type D1
Policies: changes to development standards
Los Angeles recently passed an ordinance changing the FAR standards for more than 300,000 properties across the city
Policies: remove barriers
• Reducing off-street parking requirements
•
• Allowing Accessory Dwelling Units (ADUs)
Policies: provide incentives
Policies: direct development to places where it fits
Chicago
1950
Population Densities of U.S Cities: 1950 - 1990
1950
1950
1950
1950
Indy Denver Columbus K.C.
Pers
ons
per s
quar
e m
ile
1990
15,000
10,000
5,000
1990
1950
1990 1990
1990
1950
Source: US Census
What will be the places we will want
to sustain in the future?
Jim LindbergNational Trust for Historic Preservation
Mountains/Plains Office, Denver
Thank You.
www.PreservationNation.org
U.S.
20.0 sf
Shopping Center Space Per Person
3.3 sf2.5 sf 2.3 sf
1.1 sf
Sweden U.K. France Italy
Squa
re fe
et p
er p
erso
n
Walmart
Total retail area in U.S. doubled, from 19 square feet per person in 1990, to 38 square feet per person in 2005.
6,000 chain outlets to close in 2009 250 vacant Walmarts 1.2 Billion SF of vacant retail space
Source: Shopping Center Today