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environmental profi le of the paved skin, while the installation accounts for the
greatest share of the burdens in subterranean networks. The best design consists of
concrete sidewalks, asphalt pavements, HDPE (high density polyethylene) gas
pipes, PVC (polyvinyl chloride) water pipes, and concrete sewer pipes. Pavements
and sidewalks are the most contributing elements to the overall environmental
burdens of streets.
Keywords City developments • Life cycle assessment • Life cycle management
• Life cycle thinking • Pavements • Sidewalks • Sustainability
1 Introduction
More than 50 % of world’s population is concentrated in cities, although they occupy
less than 2 % of the Earth’s surface. Because of the intense activity of cities, which
play an essential role in the global socio-economic development, they consume over
75 % of the world’s resources, between 60 % and 80 % of total energy, and are
responsible for approximately 75 % of global greenhouse gas (GHG) emissions (Ash
et al. 2008 ; Kamal-Chaoui and Robert 2009 ; Pacione 2009 ; UN Population Division
2010 ; European Union 2011 ; Lazaroiu and Roscia 2012 ). Environmental awareness
of the urban metabolism has raised due to the rapid urbanization patterns. As a result,
policy and planning highlight the importance of promoting environmental strategies
that increase the sustainability of cities (UN 2013 ).
Within cities, public spaces play a key role in supporting daily urban life.
According to UN-HABITAT ( 2013a , b , c , d ), four main issues might be considered.
First, streets may become a matrix which increases the urban connectivity between
people and activities thereby making mobility more effi cient. Second, the street
pattern hosts urban basic services, such as water supply. Third, public space is a key
element for the cultural and political dimensions of cities. Finally, street design
might enable the pedestrian and road mobility in a safe manner. Thus, streets are
composed of multiple elements from diverse natures that satisfy the different
functionalities of the public space (UN-HABITAT 2014 ).
The urban fabric is in constant change because of new city developments,
maintenance and partial renewals due to the intense urban activity. The World Wide
Fund for Nature (WWF) accounted for $350 trillion of expenditure on urban infrastructures in the coming decades. Assuming business-as-usual (BAU) conditions,
these projects would contribute to around 465 Gt of GHG emissions (WWF 2008 ).
Then, if no environmental criteria are applied in the urban planning design (i.e.,
aesthetic or economic criteria are prioritized), the global environmental burdens of
cities can dramatically increase. Furthermore, the consideration of all the life cycle
stages to account for the environmental burdens of urban elements is basic for
understanding their environmental performance, as demonstrated by Oliver-Solà et al.
( 2009a , b , c ), Mendoza et al. ( 2012a , b ), Petit-Boix et al. ( 2014 ), Sanjuan-Delmás
et al. ( 2014 ).
X. Gabarrell et al.
environmental profi le of the paved skin, while the installation accounts for the
greatest share of the burdens in subterranean networks. The best design consists of
concrete sidewalks, asphalt pavements, HDPE (high density polyethylene) gas
pipes, PVC (polyvinyl chloride) water pipes, and concrete sewer pipes. Pavements
and sidewalks are the most contributing elements to the overall environmental
burdens of streets.
Keywords City developments • Life cycle assessment • Life cycle management
• Life cycle thinking • Pavements • Sidewalks • Sustainability
1 Introduction
More than 50 % of world’s population is concentrated in cities, although they occupy
less than 2 % of the Earth’s surface. Because of the intense activity of cities, which
play an essential role in the global socio-economic development, they consume over
75 % of the world’s resources, between 60 % and 80 % of total energy, and are
responsible for approximately 75 % of global greenhouse gas (GHG) emissions (Ash
et al. 2008 ; Kamal-Chaoui and Robert 2009 ; Pacione 2009 ; UN Population Division
2010 ; European Union 2011 ; Lazaroiu and Roscia 2012 ). Environmental awareness
of the urban metabolism has raised due to the rapid urbanization patterns. As a result,
policy and planning highlight the importance of promoting environmental strategies
that increase the sustainability of cities (UN 2013 ).
Within cities, public spaces play a key role in supporting daily urban life.
According to UN-HABITAT ( 2013a , b , c , d ), four main issues might be considered.
First, streets may become a matrix which increases the urban connectivity between
people and activities thereby making mobility more effi cient. Second, the street
pattern hosts urban basic services, such as water supply. Third, public space is a key
element for the cultural and political dimensions of cities. Finally, street design
might enable the pedestrian and road mobility in a safe manner. Thus, streets are
composed of multiple elements from diverse natures that satisfy the different
functionalities of the public space (UN-HABITAT 2014 ).
The urban fabric is in constant change because of new city developments,
maintenance and partial renewals due to the intense urban activity. The World Wide
Fund for Nature (WWF) accounted for $350 trillion of expenditure on urban infrastructures in the coming decades. Assuming business-as-usual (BAU) conditions,
these projects would contribute to around 465 Gt of GHG emissions (WWF 2008 ).
Then, if no environmental criteria are applied in the urban planning design (i.e.,
aesthetic or economic criteria are prioritized), the global environmental burdens of
cities can dramatically increase. Furthermore, the consideration of all the life cycle
stages to account for the environmental burdens of urban elements is basic for
understanding their environmental performance, as demonstrated by Oliver-Solà et al.
( 2009a , b , c ), Mendoza et al. ( 2012a , b ), Petit-Boix et al. ( 2014 ), Sanjuan-Delmás
et al. ( 2014 ).
X. Gabarrell et al.