Paper prepared to support CIB’s Agenda 21 for Sustainable Construction for Developing Countries
Accepted by Building Res. Inf.
ON AGENDA 21 FOR LATIN AMERICAN AND CARIBBEAN
CONSTRUBUSINESS - A PERSPECTIVE FROM BRAZIL
Vanderley M. John1,3; Vahan Agopyan2; Christer Sjöström3
(1)
John@poli.usp.br; (2) Vahan.Agopyan@poli.usp.br 3christer.sjostrom@hig.se
Department of Civil Construction Engineering, Escola Politécnica, University of São Paulo
www.pcc.usp.br, Cidade Universitária, 05508-900 São Paulo, SP Brazil
(3)
Centre for Built Environment – University of Gävle – Gävle, Sweden
1,2
ABSTRACT
The subject of this paper is about an analysis of the challenges to make this complex sector
more sustainable in the Latin American and Caribbean (LAC) region. The regional economic,
social and environmental characteristics are presented. The relative size of the
construbusiness in LAC economies is discussed. The relative importance of its environmental
loads is discussed based on available CO2 generation data as well as on some available local
studies’ results of construction wastage and construction and demolition waste generation
rates.
Some items to be included in a regional Agenda 21 for the Construbusiness are presented
based on the regional specificities as well as on the global Agenda 21 for Sustainable
Construction proposed by CIB. Reducing building material wastage, increasing the use of
recycling wastes to new building materials, energy efficiency in buildings, water
conservation, indoor air quality, quality of products and processes, durability and
maintenance, social aspects are treated amongst others as important issues to be in a regional
Agenda 21. The regional vision on Sustainable Construction is accessed by the ongoing
regional actions. Challenges for the research communities are identified.
1. INTRODUCTION
Construbusiness is a word in English (etymology: construction + business) created by Brazilian
construction associations to describe the totality of the construction business related activities. It
includes as role-players the building contractors, designers, materials producers, building systems
producers, financial agents, researchers, governmental institutions, water, telephone, electricity and
sewage suppliers, environmental organizations and consumers. It was created as an analogy with the
agribusiness concept, conceived in the middle 1950’s to represent all agricultural related business
(MERRIAM WEBSTER’S, 2000). It is a systemic concept that implies a perception of the
construction related challenges from a broader perspective, considering the interrelations between the
various role-players in the construction process and products life cycle. It also implies building and
sustaining a tight and, some times uneasy, partnership between all players in order to find new
integrated solutions to old problems or new challenges. This kind of system thinking and acting has
proved to be useful to help Brazil improve its construction industry in many aspects, including the
environmental related ones.
In the opinion of the authors, construbusiness is a way of describing and approaching the
building and construction sector that helps to successfully achieve a sustainable construction
because of its systems approach and inherent democratic way of acting. There are many
perceptions of the concept of sustainable construction but whichever view one takes, it
implies holistic thinking with regards construction and management of the built environment
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John, Agopyan & Sjöström, 2001
with a life cycle perspective. It does not only imply new environmentally-orientated
construction designs but also new, environmentally-friendly operation and maintenance
procedures. The building materials must not only be produced in sustainable way, but also
answered according to new requirements deriving from holistic environmental prerequisites.
There is no sense in producing a cladding glass in a very environmentally-friendly and
certified way if the glass sheet is going to be marketed in as a façade or a roof in a Brazilian
temperate climate.
Construction is a very big and complex industry and services network according a total
construbusiness perspective. The subject of this paper is about an analysis of the challenges to
make this complex sector more sustainable in the Latin American and Caribbean (LAC)
region. Latin America and the nearby region of Carib include 33 countries (ECLAC, 2000),
ranging from small islands to large nations like Brazil and Mexico.
This paper takes primarily a Brazilian point of view, which certainly affects its contents.
Brazil is by far the largest and certainly the most industrialized country in Latin America and
Caribbean (LAC). Perhaps due to its unique Portuguese colonization it used to be the least
integrated country in the otherwise Spanish colonized and speaking region. The paper is also a
first approach on the theme, and builds on information that is far from exhaustive.
2. CONSTRUCTION AND THE LATIN AMERICAN AND CARIBBEAN (LAC)
SOCIETIES
2.1 INTRODUCING LATIN AMERICA AND CARIB
Latin America and Carib (LAC) are the most urbanized among the developing regions of the
world. In 1995 about 74% of LAC’s 484,3 million inhabitants lived in cities (Mac Donald and
Simione, 1999). In the year 2000, 174 million of those inhabitants are estimated to be living
in one of the 59 cities larger than 750 thousand inhabitants located in the region (Mac Donald
and Simione, 1999).
Table 1 presents World Bank comparative data of Latin America and Carib (LAC) versus
developed countries. The LAC GNP is about 15% of the high-income countries. The GNP
growth has been rough following the population growth during the last five years, which
means that globalization is not improving life standards. If the average GNP is low, the
income distribution makes it worse. According to the regional average, the 10% richest earn
between 4 and 13 times more than the 40% poorest (ECLAC, 1999). As a direct result, in
1996, 36% of the households were below the poverty line in 18 of the LAC countries
(ECLAC, 1999). In most countries of the region, a wealthy economic elite has developed
consumption standards equal to those of the richer people in the developed world.
For most LAC citizens, with the possible exception of those from the socialist Cuba, their
dream is to live in a first-world society, because they believe it is the kind of society that can
assure its citizens better living standards. For these citizens, development means more
industries, cars, highways, consumer goods and, of course, better security, health and
education.
The average LAC citizen’s life is poor and is also about 9 years shorter compared to those of
the richest countries (Table 1). LAC exports mainly agricultural and mineral commodities.
Manufactured products are mere 11% of the total exported goods (Table 1).
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John, Agopyan & Sjöström, 2001
The region per capita total energy consumption is about one fifth of the higher-income
countries (Table 1) and one-eighth of the North America (WRI, 2000).
Energy is obtained in a more sustainable way. About 66% of its electrical energy comes from
hydroelectric or geothermal sources (ECLAC, 2000).
Despite having very high-polluted cities like Mexico City and São Paulo, the region does
have a relatively low per capita contribution to the major global pollution problems, like
global warming. The per capita total CO2 release is well bellow the world average (Figure 1).
It is about 6 times lower than USA and Canada and 4 times lower Germany. Considering the
CO2 fixation capacity of the forests, the LAC contribution of CO2 concentration is even
lower.
Table 1 – Comparative data between 23 countries of Latin America and the 43 countries with
the highest income (adapted from original tables of WORLD BANK, 2000)
Data Profile
1995
High income
1998
1999
Latin America and Carib
1995
1998
1999
People
Population, total (million)
Population growth (annual %)
Life expectancy at birth, total (years)
Mortality rate, infant (per 1,000 live births)
870.3
0.6
6.3
886.6
0.6
77.7
5.8
890.9
0.5
477.7
1.7
501.3
1.6
69.7
30.9
509.2
1.6
1.7
1.4
3,380
8.2
32.7
59.1
2
2.0
3,880
7.8
28.6
63.6
2.1
-0.3
3,840
8.0
29.4
62.7
Environment
Surface area (million sq km)
Forest area (million sq. km)
Forest area (%)
Annual deforestation (% of change)
Commercial energy use (kg/oil eq. per capita)
Electric power consumption (kwh)
32.1
6.4
19.9
-0.2
5,244.5
7,967.1
20.5
9.1
44.4
0.6
1,109.3
1,296.5
Economy
GDP at market prices (current 1012 US$)
GDP growth (annual %)
GNP per capita, Atlas method (current US$)
Agriculture, value added (% of GDP)
Industry, value added (% of GDP)
Services, etc., value added (% of GDP)
22.8
2.4
25,720
2.0
30.7
63.8
22.6
1.9
25,530
23.7
2.7
25,730
526.9
205.2
90.0
567.2
311.2
94.0
91.7
19.8
24.2
122.8
33.9
38.7
20.6
38.3
16.0
8.2
19.1
11.7
Technology and infrastructure
Telephone mainlines (per 1,000 people)
Personal computers (per 1,000 people)
Roads, paved (%)
Trade and finance
Trade (% of GDP, PPP)
Of manufactured exports(%)
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John, Agopyan & Sjöström, 2001
CO2 (ton per capita)
6
5
Canada and USA
4
Germany
3
2
World
1
0
1950
LAC
1960
1970
1980
1990
2000
Year
Figure 1 – CO2 per capita of Latin America and Carib, World, Germany and USA and
Canada (original data from MARLAND, BODEN & ANDRES, 2000).
The balance of payments is negative, with the current account of US $ -90 106 in 1998, a
figure more than double than in 1996 (ECLAC, 1999). As a consequence, the foreign debt
rose to US $736 109 (1998), 35 % of its total GNP times.
As a whole, LAC countries are becoming poorer. During the last decade most of the LAC
countries were deeply committed to reducing their inflation rate. Nowadays, annual inflation
rates are typically bellow 12% and the governments are still conducting a strict fiscal policy,
reducing the public deficit, with significant reduction of social investment. The interest rate is,
in general, much higher than in higher-income economies (CALCAGNO, MANUELITO &
RYD, 2001).
LAC is one of the most forested regions of the world, with about 44% of their land covered
by forest (see Table 1, WORLD BANK, 2000). This rate is double that observed in the
higher-income nations. A major problem is that about 90% of LAC forest area is in the
Amazon region. It covers 40% of Brazil’s total area, and also parts of Bolivia, Colombia,
Ecuador, Guyana, Peru, Suriname and Venezuela. It constitutes 70% of the world’s
rainforests and 20% of the world’s fresh water (The Amazonian Parliament, 2001). The
preservation of this enormous forest seems to guide most of the international efforts related to
sustainability in LAC.
LAC also have abundant water resources (Table 2), despite the fact that water is a scarce
resource in some regions, like in some inland areas of the Northeast of Brazil as well as in big
cities, like São Paulo.
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John, Agopyan & Sjöström, 2001
Table 2– Freshwater resources and withdrawals in LAC region in comparison with other
regions and the world (WRI, 2001). Dom = domestic. Ind. = industry. Agr. – agriculture
Region
World
Europe
South America
Central America /Carib
Costa Rica
El Salvador
Mexico
Bolivia
Chile
Brazil
Availability
per capita
(m3/year)
Withdrawals
per capita
(%)
Sectoral Withdrawals
(%)
Agr..
Ind.
Dom
7,045
3,981
34,791
6,290
27,936
2,820
4,136
37,941
61,007
31,849
9
18
1
10
5
4
19
0
2
1
67
39
60
X
80
46
78
87
84
61
19
45
11
X
7
20
5
3
11
18
9
14
20
X
13
34
17
10
5
21
Year
1995
1995
1995
1995
1997
1992
1998
1987
1987
1992
2.2 CONSTRUBUSINESS IN LAC
In several ways, LAC is under construction. Somewhere between 76 and 84 % of the 3,1x106
km of LAC roads are still unpaved (Table 1 and ECLAC, 2000). Traditional paving is known
to use a great amount of natural resources. In higher income countries about 94% of the roads
are already paved.
Shantytowns are part of the built environment in most of the countries. In 19 countries of the
region there is a need to construct 17 million new houses (MAC DONALD & SIMIONI,
1999). In São Paulo and Rio about 20% of the population live in shantytowns
(CLICHEVSKY, 2000).
Modern urban infrastructure, like piped water, electricity and sewage piping systems are
relatively scarce in LAC (Table 3). Sewage treatment is even more rare because the piping
systems are expanding faster than the treatment stations (ECLAC, 2000 b). In 1996, the InterAmerican Development Bank’s estimation was that only 5 to 10% of the wastewater
undergoes proper treatment (FOSTER, 1996).
Table 3– Houses with services (% of total). Data from ECLAC (2000) from years 1990 and
1980 related to 19 LAC countries
Max
92.5
84.2
99.4
Piped water
Sewage piping system
Electric lighting
Median
76.70
52.2
85.3
Min
57.5
7.2
39.6
The contribution of the construction sector to the GNP varies highly according to
macroeconomic factors. Nevertheless, according to the Inter-American Development Bank
the share of the construction industry to the LAC’s GNP has been between 6,1% to 6,9% from
1991 to 1997 (IDB, 2001). The Inter-American Federation of Construction Chambers shows
that the participation of the construction industry is responsible for 2,5 to 11.4% of the
country formal jobs. But these figures represent only the formal portion of construction
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John, Agopyan & Sjöström, 2001
industry. In LAC a very significant portion of the houses is being built by the family members
themselves, normally with the help of relatives and friends. In Bolivia, this kind of production
scheme is responsible for 45 to 55% of the total urban houses produced every year
(CLICHEVSKY, 2000). Even so this kind of construction is part of the construbusiness,
because it uses industrial building materials most of the times. As a consequence, in Brazil,
most of the Portland cement and paint is sold to these smaller consumers.
In LAC, small local companies produce very important portion of building materials, like red
ceramic bricks. Consequently, it is difficult to obtain accurate data about its size and
environmental impact. Table4 presents some data about the production of steel-related
products and Portland cement in the region. Brazil is among the world five biggest producers
of ceramic tiles, with a production of 428x106 m2. About 90% of this amount is consumed
inside the country and 10% exported worldwide (ABC, 2001). The Brazilian Ceramic Society
(ABC, 2001) estimates an annual production of 60x106 ton of red ceramic components, like
bricks and roof tiles. About 11,000 small companies are in this very traditional business and
production losses (energy and material) are estimated to be around 30%.
The local production of building materials and self-construction scheme help make
construbusiness bigger than the construction industry in most LAC countries. For example, in
1997 the construction industry itself was responsible for 9,8% of the Brazilian GNP. In the
same year the construbusiness was 14,8% of the Brazilian GNP, with total revenue of US $
128 million (FIESP, 1999). For comparison, construbusiness is estimated to be responsible
for 11% of the European Union GNP (CIB, 1999).
Table 4 – Production of selected important building materials in LAC, Brazil and Mexico
(ECLAC, 2000)
Production (Mton)
LAC
Brazil
Mexico
1998
33 457.0
25 257
4 454
Pig iron
1997
52 448.4
26 153
14 218
Steel
1997
16 004.0
5 815
5 059
Non flat rolled steel products (1)
1995
94 629.4
28 256
24 429
Portland Cement (2)
(1) Includes bars and light sections, wire rod, rails and heavy sections.
(2) does not include Haiti
Product
Year
Number of
countries
8
> 12
> 11
23
2.3 ENVIRONMENTAL IMPACT OF CONSTRUCTION IN LAC
The global environmental impact of this sector, from raw materials extraction, materials
production, transportation, construction, use, maintenance and demolition is important. As a
result of being under construction and the high economic importance of the construction
industry, it is possible to estimate that the construbusiness environmental impact is relatively
higher in LAC than in developed countries.
Materials consumption by the LAC construction industry might well be higher than the 50%
of total material consumption estimated in Japan (KASAI, 1998) and even higher than the
75% estimated for the USA (MATOS & WAGNER, 1999).
Construction demolition waste is a result of construction wastage, maintenance and
demolition. Due to illegal deposition, it is very visible in most big cities of Latin America.
Construction and demolition waste generation estimates vary worldwide from a mere 163 kg
per capita to 3 658 per capita, with typical values above 400kg per capita (JOHN, 2000). This
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John, Agopyan & Sjöström, 2001
great variation can be explained as result of:
(a) different definitions for construction and its waste;
(b) technological differences; and
(c) the different levels of construction activity, among others.
Estimations for LAC countries are scarce. PINTO (2000) has made estimates for the
construction and demolition waste generation in 6 different Brazilian cities with populations
ranging from 242 000 to 625 000 inhabitants. From this author’s data it is possible to estimate
that per capita generation rate varies from 330 to 630 kg/year, with a median of 486kg/year.
This estimation includes informal construction but does not include residues from paving. The
same author estimates that during the construction of a typical Brazilian building 150 kg of
waste is generated per square metre. Overall, the amount of construction and demolition waste
in Brazil is considered to be significantly higher than the domestic solid waste.
In Chile, The National Environmental Commission (CONAMA) estimates an annual
generation of construction and demolition waste of 3.5x106 ton/year (MEIER, 1998), which
for a population of 14.8x106 inhabitants (ECLAC, 2000), corresponds to a generation per
capita of 236 kg/year. This amount is slightly higher than the domestic solid waste generated
in the country. SUAREZ; MALAVÉ (2000) estimates 0.06 m3 of construction waste for each
square metre of building in Colombia.
Deposition of construction demolition waste is frequently illegal because there are no or few
landfills that accept this waste in the region (UNEP, 2001), spoiling the landscape, and when
dumped in watercourses can cause urban flooding.
The transportation of the waste can represent a significant cost for the building contractor
(UNEP, 2001). In big cities of Brazil, transportation of one cubic metre of construction or
demolition waste costs between US $4.5 to 8 (PINTO, 2000), and is a wealthy and growing
business.
Materials consumption and construction waste rates are increasing due to high materials
wastage rates at building sites. Material wastage rate can be defined as the amount of material
consumed in addition to the planned amount (in percentage). Part of the wastage is actual
waste as litter and part is unnecessarily incorporated in the building. A recent Brazilian
national survey on building site material wastage was conducted by 17 Brazilian universities
and investigated 80 building sites from 52 building contractors (AGOPYAN et al., 1998). The
survey succeeded in showing that actual wastage rates (Table 5 shows some results), that are
higher than the figures assumed by the companies.
Table 5 - Building material wastage during construction both as waste and over thickness
(AGOPYAN et al., 1998). Values are expressed in percent of the planned material
consumption.
Minimum
Maximum
Median
Portland
Cement
6
638
56
Steel
rebar
2
23
9
Concrete
and
ceramic blocks
3
48
13
Sand
Ready-mix concrete
7
311
44
2
23
9
The impact of the production of Portland cement on CO2 generation is very well documented.
Figure 2 shows that the impact of the Portland clinker production is 4% of the total CO2
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John, Agopyan & Sjöström, 2001
released in the region. This value is much higher than that observed in developed countries
and is even above the worldwide average of about 3%.
CO2 from OPC (% of total)
8
Brazil
6
LAC
4
World
2
USA and Canada
0
1920
1940
1960
1980
2000
Year
Figure 2 - Participation of clinker decomposition of limestone during clinker Portland
production in the total CO2 released in Latin America and Carib, Brazil, World, and USA
and Canada (original data from MARLAND, BODEN & ANDRES, 2000). This figures
does not include CO2 due to combustion.
Buildings consume energy in all stages of its life, from the building materials production
stage to the building demolition. Table 6 from WRI (2000) shows the contribution of the use
of buildings to the total consumption of energy. It varies over LAC from about 18% in Brazil
up to 46% in the Dominican Republic, but the average is not very different from the higher
income countries. Consequently, the average LAC house uses about one-fifth of the energy of
a house located in one of the high-income nations (Table 1). The operation of buildings is
responsible for consuming more than 50% of the Brazilian electric energy (LAMBERTS &
WESTPHAL, 2000), and this share is growing. The main electricity uses in Brazilian houses
are: refrigerators (33%); water heating (26%); and lighting (23%). Air conditioning use is
growing but has still a low impact in this sector due to low saturation in the market (Geller
1991, LAMBERTS & WESTPHAL, 2000). In 1995, 40% of the Peruvian electricity was
consumed by private houses and 69% in indoor illumination (CAMPODÓNICO, 1998). The
contribution of construbusiness to global energy consumption is much higher, because these
figures in Table 1 do not include either the production phase of building and its materials or
its demolition.
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John, Agopyan & Sjöström, 2001
Region/Country
Residential
Commercial
+ Public
Agriculture
Transportati
on
Industry
Total
Table 6 – Total energy consumption distribution for economical sectors (data from WRI,
2000)
World
Europe
North America
LAC
South America
Argentina
Bolivia
Brazil
Chile
Dominican Rep
27.1
27.1
17.3
21.3
16.8
19.8
32.7
13.5
25.4
46.3
7.4
7.3
12.6
3.4
5.0
6.6
1.6
4.8
0.8
0.0
2.8
4.0
1.2
2.4
4.8
6.7
1.6
5.2
1.3
1.0
24.8
23.0
38.1
31.8
32.7
33.8
34.9
32.3
29.2
29.9
32.2
32.9
26.3
39.4
37.3
29.2
28.7
41.4
36.8
20.5
94.3
94.3
95.5
98.3
96.6
96.1
99.5
97.2
93.5
97.7
In LAC, an average 50% of the treated water is wasted due to leakage of the pipe system
(HUEB, 2000). As in the rest of the world, buildings are not the main consumers of water
(Table 2) but concentration of both buildings and population can cause local water shortage.
Because it is under construction, and because of the regions relatively low degree of
industrialization and despite the self-construction scheme, the environmental impact of
construbusiness tends to be even more important in LAC societies than it is in the highincome nations. And, it is important to note, that the infrastructure and housing construction
are expected to grow in the following years, increasing the environmental impact of the
construbusiness.
3. AGENDA 21 FOR CONSTRUCTION INDUSTRY IN LATIN AMERICA
In this first approach, the selection of items for the Agenda 21 for LAC construbusiness has
been made considering the global Agenda 21 on Sustainable Construction, prepared by the
CIB in 1999, as well as some society environmental, social and economic characteristics of
the LAC region. Environmental aspects that are now under discussion in the region are also
selected.
The CIB Agenda 21 on Sustainable Construction (CIB, 1999) describes the challenges that
the construction sector has to overcome to collaborate in a sustainable development under the
headings (1) management and organization; (2) product and building issues; (3) resource
consumption; (4) impacts of construction on sustainable urban development; (5)
environmental loads; (6) social, cultural and economic issues. In this paper, a different
approach is adopted. The suggested items to take part of an Agenda 21 for LAC’s
construbusiness are hopefully more easily perceived by the construbusiness roleplayers as an
action plan. Most of suggested items are related to more than one of the six cited CIB’s
Agenda 21 challenges.
It is necessary to mention that this chapter item is based on an original contribution of the
Department of Civil Construction Engineering of Escola Politécnica, University of São Paulo.
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John, Agopyan & Sjöström, 2001
This contribution is aimed at helping the discussion of the Brazilian local Agenda 21 for the
construbusiness (see JOHN et all, 2000).
3.1 REDUCTION OF BUILDING MATERIAL WASTAGE
Reducing material wastage has several environmental effects. It reduces the amount of
construction waste and, in the long term, the amount of demolition waste. It also reduces the
global material consumption and has an impact on construction costs, making houses more
affordable, which is very important in a region where about 50% of consumers cannot afford
a proper house.
The measured waste rates in Brazil reveal great differences in total wastage between building
sites using the same technologies (Table 5). This reveals the great influence of management,
design and culture practices on the wastage rates. Some improvement can be achieved by
education, site planning, management and design practices, but the use of new technologies
can be also important.
Waste reduction and management in building sites is also very important and has been
investigated in Chile and Brazil (CCC, 1999, PINTO, 2000, GREGOLI, 2000).
3.2 INCREASING THE USE OF RECYCLED WASTES AS BUILDING MATERIALS
When properly done, recycling wastes as building materials is a convenient way to reduce the
environmental impact of the construction industry. It has several potential environmental
advantages (Table 7): (a) helps reduce the consumption of natural resources; (b) reduces the
deposition of landfill; (c) can reduce the energy consumption on the materials production and
all its associated pollution; (d) can result in more durable materials (JOHN & ZORDAN,
2001).
The LAC’s Portland cement industry recycles industrial wastes in countries like Mexico
(CEMEX, 1999), Colombia, Chile, Argentina and Brazil. In Brazil the Portland cement
industry is the biggest recycler processing more than 5x106 ton/year of blast furnace slag and
fly ash (JOHN, 2000). Depending on the availability, clinker Portland is blended with
granulated blast furnace slag, fly ash or other pozolans, with important benefits in terms of
energy, CO2 generation among other impacts.
Most of Brazilian steel concrete rebar is produced on electric arc furnaces, using mainly steel
scrap as raw material. The Latin America Iron and Steel Institute reports that the use of the
electric arc furnaces is growing in LAC and on average, electric arc furnaces are responsible
for about 40% of the steel produced in the region (ILAFA, 2001). But the environmental
benefits of these activities are scarcely publicized to the consumers.
The Brazilian Ready-Mix Concrete Association is developing an Environmental Programme
that will include recycling water and fresh concrete, which is returned to the plant (ABESC,
2001). In Colombia, CEMEX reports that water has been recycled in three operational
concrete units, reducing the water consumption up to 30% (CEMEX, 1999).
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John, Agopyan & Sjöström, 2001
Table 7 –Environmental benefits of recycling on producing some building materials (in %
of the non recycling impact)
Environmental impact
Steel
Glass
Cement2
Energy consumption
74
6
~50
Natural resources consumption
90
54
50
Water
40
50
-
Atmospheric pollution
86
22
<502
Water pollution
76
Wastes in general
105
54
Mineral wastes
97
79
-
Sources: JOHN (2000); (2) estimation considering replacement of 50% of the clinker with fly ash, and reduction
on CO2 production.
The major challenge in this area is the recycling of construction and demolition wastes. Up to
now few Brazilian cities have recycling schemes, all of them controlled by the municipalities.
There is no report of commercial recycling within Latin American, except for the use of this
waste for land reclamation in coastal areas or quarries (UNEP, 2001). A major part of the
C&DW generated goes to illegal dumping sites, frequently obstructing waterways and
causing urban floods. Recycling construction and demolition waste as aggregate is reported as
being commercially feasible in Colombia (SUAREZ; MALAVÉ, 2000) and Brazil (PINTO,
2000). It can be done in recycling plants as well as inside the building site (GREGOLIN, 2000
and PINTO, 2000)
In Colombia, the Ministry of Environment issued in 1994 a regulation about construction
demolition waste. The Brazilian National Council in Environment (CONAMA) is discussing
similar resolution nowadays. Waste taxation is not reported but Colombian regulation allows
local authorities to tax construction demolition waste (MINAMBIENTE, 1994).
Additionally, all regions do have their own agricultural, industrial or mining residues that can
be recycled locally. It is worth mentioning the significant production of more than 5 million
tones of steel slag in LAC, of which the great part has not yet been properly recycled.
3.3 ENERGY EFFICIENCY IN BUILDINGS
It is considered possible to reduce the energy consumption of residential buildings in
Argentina, by about 50% for heating and 30% for illumination. For commercial and public
buildings the overall estimated possible reduction is 30% (BOUILLE, 1999).
LAMBERTS & WESPAHL (2000) point out several different possibilities for action to
improve energy consumption during building use. It includes education, development of
energy code, improvement of air conditioning systems, replacement of electric showers,
improvement of roof insulation, use of solar energy to heat water and window improvements.
It is obviously strongly related to building and services design practices.
The Brazilian PROCEL (National Electric Energy Efficiency Programme) is already taking
actions for the improvement of the efficiency of some building appliances. The Mexican
CONAE (National Commission of Energy Conservation) has been working on appliances as
well as in the building itself to limit the maximum density of electrical power in illumination
of non-residential buildings (CONAE, 1995)
Also, there is significant room for improvement of energy efficiency in the production of
different building materials and equipments, especially in those produced by small companies.
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John, Agopyan & Sjöström, 2001
3.4 WATER CONSERVATION
Despite the great water availability, water shortage is a problem in several areas of LAC.
There is lack of detailed data on water consumption in buildings in Brazil (JOHN, 2000) and,
probably, in LAC as a whole.
Brazil is structuring its National Water Conservation Plan (PNCDA, 2001), which includes
specific actions for buildings. The Rational Use of Water Programme of State of São Paulo
(PURA) succeeded in reducing water shortages in the LAC biggest city. The Mexican
government has its Program on Efficient Use of Water in Public Buildings.
The reduction of water consumption in buildings results from a combination of education of
the users with design and technical changes. Water metering systems, harvesting rain water,
re-using served water, low volume WC, aerated and self-closing faucets, waterless
technologies, can be mentioned. Most of these methodologies and technologies are already
available in the Brazilian market (JOHN et all, 2000).
3.5 IMPROVING INDOOR AIR QUALITY
Nowadays, indoor air quality is considered to be a relevant subject in large Brazilian
commercial buildings (BRICKUS et all. 1998).
In 1998 the Ministry of Health issued a directive on the indoor air quality (Portaria 3523,
28/08/1998) requiring specific procedures for maintenance and hygiene of air conditioning
systems in large buildings (TROTTA & ARAÚJO, 2000). But with the increase on the use of
air conditioning in houses (LAMBERTS & WESTPHAL, 2000) its importance will certainly
grow in the near future to include almost every building.
In colder regions of LAC countries, mainly Argentina, Chile and the Andean Community,
indoor air quality problem is probably more important, due to the heating of houses through
burning biomass or fossil fuels without proper precautions.
3.6 IMPROVEMENT OF THE QUALITY OF CONSTRUCTION PROCESS AND PRODUCTS
There is no possible environmental action without a systemic and successful quality scheme,
because the defects are an expensive form of wasting environmental resources. Then, the
ongoing efforts for quality improvement within the construbusiness sector must be
intensified.
In the last 10 years, Brazil developed the PBQP-Habitat (Brazilian National Programme for
Quality and Productivity in the Habitat) aiming at solving the construbusiness’ quality related
problems. The steering Committees of PBQP-Habitat and its regional branches gather
representatives of all construbusiness, from material producers associations, financing agents,
governmental institutions, research and professional associations, building contractors
associations. For each building product, activity or business a specific project is developed to
improve its overall quality, environment, and productivity as well as voluntary certification
schemes.
The Mercosur and Chilean Forum of Quality and Productivity in Housing was founded in
1999 and aims at improving quality and sustainability in housing within the region.
3.7 DURABILITY AND MAINTENANCE
Increasing the knowledge on the service life of the built environment, and the capability of
generating and managing life data are certainly a major challenge for achieving a more
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John, Agopyan & Sjöström, 2001
sustainable construction industry (SJÖSTRÖM, 2000). This does not only concern the
physical but also the functional durability of the constructed asset, and includes the
optimization of the service life in all phases of the building process. This in turn requires from
a building, the flexibility and capacity of being upgraded.
In Brazil, the research on durability is almost completely limited to reinforced concrete
structures. As a result the last version of the Brazilian Design Concrete Structures Standard
has made important advances in this field. This kind of approach must be extended to all other
technologies and materials construction.
Maintenance is rarely a major concern during a construction design and some established
building technologies require frequent and expensive maintenance activities. Durability and
maintenance are also a relevant topic of discussion in public works. Concepts like life cycle
costs should be implemented to select more competitive technologies.
3.8 OTHER ASPECTS
Hygiene and health in building sites are certainly a major problem in the region (CLARIN
DIGITAL, 1997; CNC, 2000; SAURIN et all, 2000).
The recent ban of asbestos in Chile (LA TERCERA, 2001) and in some Brazilian cities with
the discussion of a comprehensive asbestos ban in whole country – are connected with this
subject but also raise the question of the use of environmentally safe building materials in
general. Asbestos is used mainly as reinforcement in cement sheets, pipes and water tanks.
Environmental impacts of building sites – vegetation protection, dust (CCC, 1998B) and noise
(CCC, 1998) generation are also relevant and important issues.
3.9 SOCIAL ASPECTS
An Agenda 21 for Sustainable Construction in LAC must include the ambition of a better life
for the entire population. This will certainly require a significant improvement and
enlargement of the built environment, including more environmentally sound houses and
infrastructure.
To meet such a goal will require the sector to work closely with other social roleplayers
interested in overcoming these problems. But the goal also introduces technical challenges,
mainly those related to the development of new technological solutions that should have at the
same time low financial cost and low environmental impact.
4. THE VISION OF SUSTAINABILITY OF CONSTRUCTION IN LAC’S
Several industrial associations and companies already have in their catalogues and/or their
own environmental agenda far reaching environmental ambitions, including e.g.
environmentally-friendly products. The Brazilian Ready Mix Concrete Association (ABESC,
2001) and the giant cement worldwide active Mexican company CEMEX (CEMEX, 1999)
are examples. CEMEX and Votorantim, the biggest Brazilian cement producer, are active
members of the international project “Toward a Sustainable Cement Industry”, sponsored by
the World Business Council for Sustainable Development (WBCSD, 2001). In Brazil there
are a growing number of building projects that claim to be environmentally-friendly, mainly
because they manage to preserve some of the native vegetation.
The Letter of San Salvador, issued as a conclusion of the FIIC’s (Inter-American Federation
of Construction Chambers) XXI Congress on Housing asks for official incentives for
13
John, Agopyan & Sjöström, 2001
companies that adopt lean construction methods. The FIIC is promoting in 2001, its Second
Latin American Contest on Sustainable Housing and Urban Development. The Construction
Chamber of Chile does have a formal Environmental Policy. In 2001 the Chamber is
promoting a national environmental contest, focused on building site noise and dust control,
waste management as well as environmental management. The Chilean chamber is also
distributing among its members the English version of CIB Agenda 21 on Sustainable
Construction.
The Environmental Chamber for Construction of the State of São Paulo is taking several
environmental actions, mainly those related to the protection of vegetation, noise pollution by
highways, sewage treatment and CDW reduction and recycling. The Brazilian PBQP-Habitat
and The Mercosur and Chilean Forum of Quality and Productivity in Housing are intended to
act in sustainability issues, but very few activities have been carried out on the subject to
improve the overall quality.
Chile, Argentina and Brazil are engaged in the Green Building Challenge. Recently the CIB
Symposium on “Construction and Environment – from theory into practice” as well as the
CIB W 62 Int. Symp. Water Supply and Drainage was held in Brazil. The CIB Agenda 21 on
Sustainable Construction has been translated to Brazilian Portuguese. The Brazilian National
Built Environment Researchers Association has several scientific committees working on
Agenda 21 related aspects and one specifically devoted to Sustainability issues on
construction. Its last National Congress was about Sustainability.
Despite all these activities, there is a lack of a more systemic approach towards sustainable
construction and co-ordination among the different construbusiness roleplayers. Since the
environmental impact of a construction facility depends on the environmental impact of each
different component, co-ordination of activities seems to be important. From this point of
view, the construbusiness approach adopted by the Brazilian PBQP-Habitat seems to be very
interesting.
It will be very important to build synergistic networks capable of offering comprehensive
environmental-friendly solutions for buildings and other construction products, increasing
their marketing appeal. This kind of action will help consumers to easily realize the options
available for protecting the environment when commissioning, buying or refurbishing
buildings. Such networks must also help the development of building assessment methods to
be used even during the design phase (SILVA, AGOPYAN & JOHN, 2000), making it
possible to demonstrate the environmental benefits of the proposed solutions.
5. BARRIERS FOR SUSTAINABLE CONSTRUCTION
The conclusion of the UN LAC diagnosis on policies and governmental institutions for
sustainability appointed two major barriers: (a) lack of effective power of the (governmental)
environmental institutions; and (b) the low degree of environmental concern among the
citizens (OCAMPO, 1999).
In a region greatly marked by poverty and economic problems, it is very difficult to establish
the environment as a national priority. For example, in LAC the measurement of urban air
quality is not a rule. Only Brazil, Mexico and Chile have good measurements networks
(KORK; SAÉNZ, 1999). Also, there is a lack of basic legislation for waste, even most
landfills do not comply with sanitary standards (ACURIO et al., 1997).
14
John, Agopyan & Sjöström, 2001
Consequently, the sustainability actions are focused on poverty, democracy, human
settlements and preservation of natural resources. Chile is probably the only country of LAC
that is developing sustainability policies for the different industrial sectors.
Financing is a very important barrier to sustainability. Any technical solution that increases
the total price of housing or infrastructure will probably face significant opposition especially
if aimed at low cost housing.
6. CHALLENGES FOR THE RESEARCH COMMUNITY
The research community in LAC is relatively small, with the national investment in research
below 0.8% of the GNP (HILL, 2000). Nevertheless, there are active research groups in the
region covering most of the suggested Agenda 21 topics. Certainly research partnerships
among different countries will reduce the cost and length of time required to solve the main
technical problems.
There is an urgent need for benchmarking of different environmental aspects, like materials
wastage, energy and water consumption, construction and demolition waste generation, and
indoor quality. Good benchmarking will help to establish priorities for the Agenda 21
ambition and work and its related research needs. It will also allow the measurement of the
results on every aspect of the Agenda 21 action.
In the region there is also a lack of comprehensive and reliable data about the different
environmental loads of building materials production, building operation etc. Therefore, it is
very difficult to establish and perform Life Cycle Assessment studies. It is, in addition,
important to work on environmental assessment tools for buildings adapted to LAC needs.
The development of new and environmentally-friendly construction materials is a challenge.
Recycling construction and demolition and other local wastes can be a valuable
environmental tool in LAC.
Research and development on environment-related management aspects is essential because a
organizational and managerial transformation is necessary to give support to the sustainability
issues (CIB, 1999). One immediate goal in this research area for LAC construbusiness is to
develop management techniques to reduce material wastage at building sites as well for
quality management.
The investigation of the relationship between architectural design and sustainability in LAC
must be clarified. Additionally, a more sustainable construction process will require design
tools that allow the consideration of sustainability issues like energy, water and materials
consumption at the design.
Improving the durability knowledge of construction is, as mentioned, a major challenge.
There is a lack of regional data to support the service life design of buildings. The
development of a LAC network on durability of building materials and buildings would be a
major achievement.
The research community has already developed environment-related knowledge, like the
passive and low energy architecture design tools and technologies, but most of this knowledge
is not transferred to the market. Consequently, the creation of better mechanisms to allow the
transference of knowledge from research institutions to the market is a key issue to be
addressed. A common Agenda 21 on sustainable construction could help also in this subject.
Finally, a sustainable construction process will require professionals with better
environmental knowledge. This, in turn, will require new, improved and environmentally15
John, Agopyan & Sjöström, 2001
oriented education, technical handbooks in all fields, like building materials, building
systems, etc.
7. CONCLUSIONS
The impact of construbusiness in the environment in Latin America and Carib is probably
more important than it is in developed countries. This is due to the fact that LAC is still under
construction and the regions have a relatively low degree of industrialization. The
implementation of an Agenda 21 for Sustainable Construction in the region is considered to
be very important.
Reducing building material wastage, increasing the use of recycling wastes as building
materials, energy efficiency in buildings, water conservation, indoor air quality, quality of
products and processes, durability and maintenance and social aspects among others, are
important issues to be included in a regional Agenda 21.
There are several environmental initiatives being carried out by institutions connected to the
construbusiness. Developing a better co-ordination among the different players of the
construbusiness will help develop and implement a consistent Agenda 21 in the region.
However, there are important barriers. The most important one is perhaps the low degree of
environmental concern among the LAC citizens.
The relatively small regional research community will have to adjust to answer the new
challenges. Co-operation between countries is important and has to be improved.
8. ACKNOWLEDGMENTS
This research has been supported by FAPESP. The authors would like to thank the InterAmerican Federation of Construction Chambers and Construction Chamber of Chile for their
assistance.
9. REFERENCES
ABC (Brazilian Ceramic Society) Cerâmica no Brasil: Panoramas
http://www.abceram.org.br/cerambrasil/panoramas/index.htm 12/Feb/2001
Setoriais.
ABESC (Brazilian Association of Ready Mix Concrete) Concreto e o meio ambiente.
http://www.abesc.org.br/meio/meio.htm February 14, 2001
ACURIO, Guido; ROSSIN, Antonio; TEIXEIRA, Paulo Fernando; ZEPEDA, Francisco Diagnóstico
De La Situación Del Manejo De Residuos Sólidos Municipales En América Latina Y El
Caribbean. Organización Panamericana de la Salud - Organización Mundial de la Salud. Serie
Ambiental No 18. 2nd Edition. Septiembre de 1998
AGOPYAN, V. (coordinator). Alternativas para a redução do desperdício de materiais nos
canteiros
de
obras.
Relatório
Final.
São
Paulo
:
EP
USP,
5v.
1998
(http://www.pcc.usp.br/pesquisa/perdas)
BOUILLE, Daniel Lineamientos para la regulación del uso eficiente de la energía en Argentina.
ECLAC/UN, Santiago de Chile, 1999, 71p. (Serie Medio Ambiente y Desarrollo Nro 16
BRICKUS, Leila S.R.; CARDOSO, Jari N.; DE AQUINO NETO, Francisco R. Distributions of
indoor and outdoor air pollutants in Rio de Janeiro, Brazil: implications to indoor air quality in bayside
offices, Environmental Science and Technology, Volume 32, Issue 22, 15 November 1998, Pages
3485-3490
16
John, Agopyan & Sjöström, 2001
CALCAGNO Alfredo; MANUELITO, Sandra; RYD, Gunilla. Proyecciones latinoamericanas 20002001 Estudios estadísticos y prospectivos 5. United Nations, ECLAC, Santiago de Chile, 2001
CAMPODÓNICO, H. Las reformas energéticas y el uso eficiente de la energía en el Perú.
ECLAC/UN, Santiago de Chile, 1998, 72p. (Serie Medio Ambiente y Desarrollo Nro. 12)
CCC (Camara Chilena de la Construcción) Control de Polvo en Obras de Construcción.
Edición Agosto 1998b. 26p (Manual de la Construcción Limpia,2 ).
CCC (Camara Chilena de la Construcción) Control de Ruido en Obras de Construcción
1998. 39p (Manual de la Construcción Limpia,1 ).
CCC (Camara Chilena de la Construcción) Gestión de Residuos Sólidos en la Construcción Edición
1999. 27p . (Manual de la Construcción Limpia; 3)
CCC (Camara Chilena de la Construcción) Construcción Sustentable – Un desafio país. Boletín
Estadístico Nº326, enero de 2001 P. 36-39
CEMEX Environmental and Health Report. 1999 16p.
CIB Agenda 21 on sustainable construction. CIB Report Publication 237. 1999
CLARIN DIGITAL Las ART no cumplen con su función. Miércoles 16 de abril de 1997, Buenos
Aires. http://www.clarin.com.ar/diario/97-04-16/art01.htm February 15, 2001
CLICHEVSKY, Nora Informalidad y segregación urbana en América Latina. Una aproximación.
Serie Meio Ambiente y Desarrollo. United Nations, ECLAC, Santiago de Chile, 2000
CNC (CÁMARA NICARAGÜENSE DE LA CONSTRUCCIÓN) Los accidentes se pueden evitar
¿Inversión o gasto? Arquitectura & Construcción Jun. 2000 p.5
CONAE (Comission Nacional para el Ahorro de Energia) Eficiencia energética para sistemas de
alumbrado en edificios no residenciales. NOM-007-ENER-1995.
ECLAC (Economic Commission for Latin American and Caribbean) Statistical Yearbook 1999.
United Nations : Santiago de Chile, 2000.
ECLAC (Economic Commission for Latin American and Caribbean) Economic Indicators. United
Nations, Santiago do Chile, 1999
ECLAC De la urbanización acelerada a la consolidación de los asentamientos humanos en
américa latina y el Caribbean: el espacio regional. Conferencia Regional de América Latina y el
Caribbean. Santiago de Chile, 25 al 27 de octubre de 2000b. 99 p
FIESP (Industry Chamber of São Paulo) Construbusiness 1999 – Housing, infrastructure and
employment. São Paulo, FIESP/Trevisan, 1999.
FIIC (Inter-American Federation of Construction Chambers) La Declaracion De San Salvador. XII
Congreso Interamericano de Vivienda. San Salvador, 5 de octubre de 1999
FOSTER, Vivien Policy Issues for the Water and Sanitation Sectors. Inter-American Development
Bank, Washington, D.C. August 1996 (No. IFM96-101) 24p.
GREGOLI, A.S. Management in the production and utilization of the waste material in the
construction site. In: CIB Symposium Construction and Environment. Theory to practice. São
Paulo, PCC USP/CIB, 2000
HILL, Derek Latin America: R&D Spending Jumps in Brazil, Mexico, and Costa Rica. National
Science Foundation, Division of Science Resources Studies (NSF 00-316). Arlington, VA 2000 5p
HUEB, José Augusto El programa de control de perdidas como estrategia para el desarrollo de
instituciones de agua potable y saneamiento (HDT 34). CEPIS/WHO/UN, http://www.cepis.opsoms.org/ February 14, 2001.
IDB Statistics and Quantitative Analysis Unit calculations based on official statistics of member
countries. http://www.iadb.org/int/sta/ENGLISH/staweb. Feb/11/2001
17
John, Agopyan & Sjöström, 2001
ILAFA (Latin America Iron and Steel Institute) Latin America Steel Production 1999.
http://www.ilafa.org/ingles/indexi.htm 14/02/2001
IMTA
Programa
de
Uso
Eficiente
del
Agua
en
.http://www.imta.mx/otros/uso_eficiente/home.html February 15, 2001
Inmuebles
Federales
JOHN, V.M. Recycling of Wastes in Construction: A contribution to a methodology for research
and development. Escola Politécnica, USP, 2000. Tese de Livre Docência. (In Portuguese)
JOHN, V.M., ZORDAN, S. E. Research & development methodology for recycling residues as
building materials - a proposal. Waste Management 21 (2001) 213±219
JOHN, V.M.; AGOPYAN, V.; ABIKO, A. K.; PRADO, R. T. A.; GONÇALVES, O.M. SOUZA, U.
E. Agenda 21 for the Brazilian construction industry – a proposal. In: CIB Symposium Construction
and Environment. Theory to practice. São Paulo, PCC USP/CIB, 2000
KORK, M.E.; SAÉNZ, R. Monitoreo De La Calidad Del Aire En América Latina. Centro
Panamericano de Ingeniería Sanitaria y Ciencias del Ambiente – OMS Lima 1999
LA
TERCERA
Pionero
ambiental.
19.08.3a.EDI.EDIT3.html. 19 de Enero de 2001
http://www.tercera.cl/diario/2001/01/19/t-
LAMBERTS, R.; WESTPHAL, F. Energy Efficiency in Buildings in Brazil. In: Construction and
Environment: from theory into practice. CIB PCC USP,
MAC DONALD, Joan; SIMIONI, Daniela Consensos urbanos. Aportes del Plan de Acción
Regional América Latina y el Caribbean sobre Asentamientos Humanos. CEPAL Serio Medio
Ambiente e Desarrollo 21. Santiago de Chile, 1999, 76p.
MARLAND, Gregg; BODEN, Tom; ANDRES, Robert J. CO2 Emissions from Fossil-Fuel Burning,
Cement Manufacture and Gas Flaring 1751-1997. Carbon Dioxide Information Analysis Center.
http:cdiac.esd.ornl.gov/trends. 09/Feb/2001
MEIER, José Propuesta De Politica Nacional Para La Gestion De Los Residuos. CONAMA,
Santiago, 1998 (Power Point Presentation Supplied by FIIC)
MERRIAM WEBSTER’S Collegiate Dictionary. http://www.m-w.com/cgi-bin/dictionary. 2/10/2001
MINAMBIENTE (Ministerio Del Medio Ambiente) Resolucion no. 541 del 14 de diciembre de 1994
(http://www.minambiente.gov.co/MinAmb/Normas/RESOLUCIONES/
R005411994/R005411994.html)
OCAMPO, José Antonio Políticas e instituciones para el desarrollo sostenible en América
Latina y el Caribbean. . ECLAC/UN Serio Medio Ambiente e Desarrollo 18. Santiago de Chile,
1999,22p.
PBQP-Habitat Fórum Mercosul e Chile da Qualidade e Produtividade na Habitação
http://www.pbqp-h.gov.br/brasil-ue/forum.html. 1999 (13/2/2001)
PINTO, T.P. Recycling in construction sites: environmental responsibility and cost reduction. In: CIB
Symposium Construction and Environment. Theory to practice. São Paulo, PCC USP/CIB, 2000.
PINTO, T.P. Recycling in construction sites: environmental responsibility. In: Construction and
Environment: from theory into practice. CIB PCC USP, 2000
PNCDA Programa Nacional de Combate ao Desperdício de Água. http://www.pncda.gov.br. February
15, 2001
SAURIN, Tarcísio Abreu; LANTELME, Elvira Maria Vieira; FORMOSO, CARLOS TORRES.
Contrubuições para a revisão da NR-18 : condições e meio ambiente de trabalho na construção
civil, relatório de pesquisa. Porto Alegre, RS. 2000. 140p
SILVA, V.G.; SILVA, M.G.; JOHN, V.M; AGOPYAN, V. The role of architectural decision-making
process in environmentally responsible buildings. In: Construction and Environment: from theory into
practice. Proceedings. São Paulo, CIB/PCC.USP/November 23-24, 2000. (publicado em CD-Rom)
18
John, Agopyan & Sjöström, 2001
SJÖSTRÖM, C. Durability of building materials and components. In: Construction and
Environment: from theory into practice. CIB PCC USP, 2000
SUAREZ, C.J.; MALAVÉ, R.E. Proposal for the commercialization of recycled construction waste in
Barquisimeto City, Venezuela. In: CIB Symposium Construction and Environment. Theory to
practice. São Paulo, PCC USP/CIB, 2000.
THE
AMAZONIAN
PARLIAMENT.
Los
mitos
de
http://www.webmediaven.com/parlamaz/amazonia.html February 15, 2001
la
Amazonia.
TROTTA,A.C.; PRADO, R.T.A. Qualidade do Ar Interior. PCC USP, 2000 35p (Texto Técnico
PCC 23)
UNEP International Source Book on Environmentally Sound Technologies (ESTs) for Municipal
Solid Waste Management (MSWM). http://www.unep.or.jp/ietc/ESTdir/pub/MSW/index.html
February 15, 2001
WORLD BANK Source: World Development Indicators database. July 2000
WRI (World Resources Institute) World Resources 2000-2001 - People and Ecosystems: The
Fraying Web of Life. Washington DC, 2001
WBCSD Toward a sustainable cement Industry http://www.wbcsdcement.org/default.asp
19