• Ildefons Cerda • Barcelona in Turmoil • Plan of Ensanche • Cerda's Five Categories: Technical, Political, Economic, Legal & Administrative • Birth of Comprehensive Planning • The Grid • The Intevia • The Intevia Network • Natural Light and Air • Logical Justification • Public Facilities • Policy Implementation • Practical Evolution • A Study by Dan Anthony

1. Ildefons Cerda
and the Plan for Extension in Barcelona

2. Ildefons Cerdà
Born: December 23, 1815 in Centelles, Catalonia, Spain
Died: August 21, 1876
• Civil Engineer from the Escuela de Ingenieros de
Caminos, Canales y Puertos.
• Joined the Corps of Engineers
• Left civil service after receiving inheritance.
• Catalan Spanish urban planner and member of
the Spanish Parliament
• Designed the “extension” of Barcelona: Eixample
• Subscribed to a higher degree of equality and
socialist ideals than his contemporaries.
• Wrote the “Teoría General de la Urbanización”
(“General Theory of Urbanization”, 1867)
• First coined the term Urbanism.

3. Barcelona in Turmoil
• The city walls came down in 1856.
• 190,000 people in 4.5 kilometers for an
average density of 42,000 people per km2
• Rapid city growth due to jobs created by the
industrial revolution.
• Unsanitary Conditions Leading to Several
Cholera Epidemics killed nearly 3% of the
population each time.
• Narrow streets as small as 1.2 meters wide
with building facades slowly encroaching into
the street.
• Sir Edwin Chadwich proved life expectancy
lower in cities (1842).
Topography by Ildefons Cerda

4. Plan of Ensanche
• Ordered city: Housing, Industry, Markets,
Social Centers
• Normative Controls: Building Height and
Depth.
• Addressed the failures of an unbridled free
market that was destroying the functional city.
• Addressed impact of the industrial revolution
and population growth especially concerning
hygiene and decreasing life expectancies.
• Antonio Rovira y Trias preserved the
segregation of classes through a hierarchy of
streets from the center
• Ildefons Cerda maintained that the equality
of social services would promote a more
productive urban culture
Plan by Antonio Rovira y Trias

5. Cerda’s Five Categories
• Technical: Engineering, planning, housing,
architecture, urban design, public health,
infrastructure, sanitation
• Political: Compromise, transactions, dialogue
and transitions
• Economic: Criteria and mechanisms funding
development and for apportioning costs and
benefits.
• Legal: Definitions of rights and duties of
property owners and the government
• Administrative: Building ordinances

6. Comprehensive Planning
• Elaborate social, demographic, housing,
economic, public health and environmental
surveys of existing conditions upon which he
based his planning proposals.
• Infrastructures designation: parks and plazas,
sidewalks and gardens, hospitals and markets,
roads and rails, water supply, sewerage, and
storm drainage.
• Detailed engineering, drainage, housing,
street circulation, and urban design studies
were submitted with the draft plan.
• Topographic survey included the
municipality of Barcelona, the inland plain,
and the six surrounding towns.

7. The Grid
His main objective in implementing the grid form
was to avoid privileged zones for social classes and to
achieve “optimal hygienic density”
Plan by Ildefons Cerda

8. Chamfered
Intersection
Block dimensions
113 m x 113 m
Only 3 Sides of
Intevia could be
built- 1863
3 Street Types -
Façade to Façade:
• Standard 20 meter minimum
• Large Avenues 30 meter
• Boulevards 50 Meters
Pedestrian Paths
5 Meters on Each Side
The Intevia
Intervia, translated as ‘block’, is a multi-functional
descriptor on what happens between streets.

9. Intevia Network
Intervia walked the line between public and private
at times creating a network of green spaces creating
momentary alternatives pathways and social
connections

10. Natural Light and Air
Intervia, translated as ‘block’, is a multi-functional
descriptor on what happens between streets.
20 meters14 meters
20 meters
20meters
16meters
Sun
Penetration
at45
degrees

11. x is the length of the side of the block;
p is the number of square meters per person;
v is the number of inhabitants per house;
b is the width of the street;
d is the height of the facade; and
f is the depth of the building site.
Logical Justification
Cerda produced numerous documents on “scientific”
urbanization, which included statistics about the
working class. The block dimension formula is
one example of a rational justification of an urban
concentration
x = +_2 pv - 2 bd
d d2
4 pv
( pvf - 2bdf - b2
d- df 2
)

12. Public Facilities
Cerdà’s facility location pattern. He attempted to
provide services equally to all inhabitants without
consideration to personal wealth. Hospitals were
located on the perimeter for sanitary reasons
Hospital
Park
Equipment (state, industry)
Market
Social Facility
Railroad
Road axis
Public Facilities
Cerdà’s facility location pattern. He attempted to
provide services equally to all inhabitants without
consideration to personal wealth. Hospitals were
located on the perimeter for sanitary reasons

13. Policy Implementation
Over time many of Cerda’s regulatory features have
been diluted and manipulated. Recently there has
been a movement to return to his original design
intentions.
1859 1860 1891 1924 1976 1988
Ample Green and Public Space
Enclosed Public made Private
Courtyards paved
Courtyards now parking lots
Ornamental stripping
Courtyards reclaimed

14. Practical Evolution
Economic pressures persuaded public officials to
loosen the regulations on public space encroaching
into the green-space until public access was no
longer possible. The infilling of Cerda’s Intevia
increased from 67,200 square meters in the
Plan Cerda in 1959 to nearly 295,000 square meters
in 1972.
Original Plan in 1859 utilizing only two sides
Increased the widths of the structures to accommodate more people
Deems courtyards only value is light. Court yards become storage.
Public space already minimized, resident now maximized
Structure only limited by light
Increase to ~300,000 m2

17. ‘Like Goethe in his agony, Barcelona asked for
more light ... It had the sun and air within reach;
from the height of its glorious but military walls,
the Barcelonans contemplated the plain that
stretched, like a fantastic Mesopotamia from the
LlobregattotheBesos,protectedbyanundulating
mountainous ridge.’
De la Puerta del Angel a la Plaza de Lesseps by A. del
Castillo & Libreria Delmau

18. Bibliography, quotes and images were taken directly from the articles listed below.
Aibar, Eduardo, and Wiebe E. Bijker. “Constructing a City: The Cerdà Plan for the Extension of Barcelona.” Science, Technology, & Human Values 22, no. 1 (1997):
3-30. http://www.jstor.org/stable/689964.
Alexander Doerr, “Behind Four Walls: Barcelona’s Lost Utopia,” Failed Architecture, , accessed August 30, 2017, https://www.failedarchitecture.com/behind-
four-walls-barcelonas-lost-utopia/.
Anthony, Dan . “Cerda Chamfre.” DAN ANTHONY. Accessed August 29, 2017. http://danthony.co/danthony/ongoing/cerda-chamfre/.
Apodaca-Cahalane, MaryDena. “Ildefons Cerdà: The True Founder of Comprehensive Planning.” Bloustein Review. Accessed August 30, 2017. http://
blousteinreview.rutgers.edu/ildefons-cerda-the-true-founder-of-comprehensive-planning/.
Bausells, Marta. “Story of cities #13: Barcelona’s unloved planner invents science of ‘urbanisation’.” The Guardian. April 01, 2016. Accessed August 28, 2017.
https://www.theguardian.com/cities/2016/apr/01/story-cities-13-eixample-barcelona-ildefons-cerda-planner-urbanisation.
Castillo, Alberto Del. De la Puerta del Ángel a la Plaza de Lesseps: ensayo de biología urbana: 1821-1945. Barcelona: Dalmau, 1945.
Density Atlas. “Eixample (Ensanche).” Density Atlas. Accessed August 29, 2017. http://densityatlas.org/casestudies/profile.php?id=92.
Neuman, Michael. “Centenary Paper: Ildefons Cerdà and the Future of Spatial Planning: The Network Urbanism of a City Planning Pioneer.” The Town Planning
Review 82, no. 2 (2011): 117-43. http://www.jstor.org/stable/27975988.
PALLARES-BARBERA, Montserrat, Anna BADIA, and Jordi DUCH. “Cerdà and Barcelona: The Need for a New City and Service Provision.” Urbani Izziv 22, no.
2 (2011): 122-36. http://www.jstor.org/stable/24920583.
Soria y Puig, Arturo, and Albert Serratosa. Cerda the five bases of the general theory of urbanization. Madrid: Electa, 1999.
Soria Y Puig, Arturo. “Ildefonso Cerdá’s General Theory of ‘Urbanización’.” The Town Planning Review 66, no. 1 (1995): 15-39. http://www.jstor.org/
stable/40113676.
Urbano, Judith. “The Cerdà Plan for the Expansion of Barcelona: A Model for Modern City Planning,” Focus: Vol. 12 (2016): Iss. 1, Article 13. DOI: 10.15368/
focus.2016v12n1.2. http://digitalcommons.calpoly.edu/focus/vol12/iss1/13
Wynn, Martin. “Barcelona: Planning and Change 1854-1977.” The Town Planning Review 50, no. 2 (1979): 185-203. http://www.jstor.org/stable/40103366.