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Green Roofs in Cairo: A Holistic Approach for Healthy Productive Cities

Conference Paper

Green Roofs in Cairo: A Holistic Approach for Healthy Productive Cities

Abstract

In Cairo, the amount of green space per inhabitant is roughly equivalent to 0.33 square meters per person (3.5 square feet), one of the lowest proportions in the world. Green roofs are presented in this study mainly as an urban landscape for healthy and productive cities. This paper describes the idea of green roofs as platform for urban faming that is considered as a holistic approach to solve environmental, spatial, social and economic problems in large cities in the developing countries. The first part of the study, presents the theoretical framework for roof farming. Potentials and problems of green roofs are analyzed and mapped in a multilayered method. The goal is to find out what the maximum potentials of productive green rooftops and determine the best techniques for maintaining them. As a result, the research presents a set of design principles, guidelines and tools that can assist in transforming existing roofs into productive roof farms. The second part of the study examines successful case studies in Cairo, including schools and residential units and introduces a broader function of roof gardens, as well as the barriers for successful implementation. The final result, point to the importance of considering green roofs as creative development opportunity for urban open spaces, responsive support for bio and food security, in addition to the climatic, environmental and aesthetical benefits. Finally, the paper presents the more interesting results and explains why this approach is successful and how the results can be extended to other cities.
Proceedings of 7th Annual Greening Rooftops for Sustainable Communities,2009, Atlanta, USA
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Green Roofs in Cairo: A Holistic Approach for Healthy
Productive Cities
Shady Attia 1and Alia Amer 1
1 Chairgroup Architecture, Faculty of Fine Arts in Cairo Helwan University.
ABSTRACT:
In Cairo, the amount of green space per inhabitant is roughly equivalent to 0.33 square meters per person
(3.5 square feet), one of the lowest proportions in the world. Green roofs are presented in this study mainly
as an urban landscape for healthy and productive cities. This paper describes the idea of green roofs as
platform for urban faming that is considered as a holistic approach to solve environmental, spatial, social
and economic problems in large cities in the developing countries. The first part of the study, presents the
theoretical framework for roof farming. Potentials and problems of green roofs are analyzed and mapped in
a multilayered method. The goal is to find out what the maximum potentials of productive green rooftops
and determine the best techniques for maintaining them. As a result, the research presents a set of design
principles, guidelines and tools that can assist in transforming existing roofs into productive roof farms. The
second part of the study examines successful case studies in Cairo, including schools and residential units
and introduces a broader function of roof gardens, as well as the barriers for successful implementation.
The final result, point to the importance of considering green roofs as creative development opportunity for
urban open spaces, responsive support for bio and food security, in addition to the climatic, environmental
and aesthetical benefits. Finally, the paper presents the more interesting results and explains why this
approach is successful and how the results can be extended to other cities.
Keywords:
Introduction:
In fact, Cairo suffers from serious problems that are similar to most other large cities in the developing
countries. The inability of the state to lead, rule and regulate, contributed to the ailing of the urban built
environment in Cairo. A bird eye view over the roof tops of Cairenes buildings will draw an alarming image.
This image represents the status of existing building roofs in Cairo and maps it out. The most striking
characteristic of the image is an overcrowded roof-landscape with junk and useless stuff. All kinds of
materials such as wood, paper, construction debris, and old furniture get thrown and left on the flat roofs.
All this stuff is not only damaging the aesthetic image of the city but is causing a serious environmental
hazard. Because the hot and dry climate, fires are reported frequently. Rodents and crawls find protection
on rooftops and cause a threat for families in upper floors of residential buildings. Also on many roofs we
can spot chickens or ducks or pigeons. The image reveals also another recent hazard that has been lately
reported. It is the avian influenza H5N1 or the so-called bird flu. In reality, poultry within Egyptian
households is a unique and very important source of income. Consequently, most of the seven million
citizens living in the informal settlement of Cairo are in particular poor and vulnerable families. Therefore,
families depend on raising mixtures of pigeons, ducks and chickens on the rooftops and backyards of their
households. In 2005, the roofs of more than 35,000 households were cleared by force for bird flu
expectation. Protection and preventive medicine team forces together with the police continue spraying
water mixed with detergents on rooftops and increase the number of patrols of garbage collection. The
other striking feature of the image is a remarkably large proliferation of satellite dishes and air conditioners
(AC) across the roofs of more affluent areas of Cairo. The roofs of Cairo that receive an annual total
Proceedings of 7th Annual Greening Rooftops for Sustainable Communities,2009, Atlanta, USA
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irradiation above 2409 bankable kWh/m2 per annum, with approximately 3300 hours of full sunshine,
witness the most outstanding paradox. The proliferation of satellite dishes versus the absence of solar
panels for water heating. Worth to mention, that the price of installing a solar thermosyphon for domestic
hot water equals the price of installing a satellite dish. Even the middle and high class families, who live in
buildings which have maintained rooftops, have problems with their roofs.
Problem:
Cairo suffers from serious problems that are similar to most other large cities in the developing countries.
Among the most visible manifestations of the challenges posed by rapid urbanization are many
environmental problems, such as pollution, dense urbanization, urban heat island effect and inversed green
house effect during winters. In fact, the dense concentration of automobiles and polluting buildings created
a negative impact on the environment. In fact, the rapid urbanization not only created environmental
problems but also economic problems. For example, air conditioners are running, over the whole summer
period, from May to September, trying to deliver an endless demand for cooling. This leads to increasing
prices of electricity bills. This is due to the lack of energy codes, which means that roofs are without or with
very poor insulation. Additionally, the city suffers from constant desert sand depositing together with
disappearance of green spaces which lead to deprivation of open space. During the last decade the city
witnessed several times inefficient food production and distribution, inaccessibly high food prices and
above all locally grown food, loaded with toxic contaminants. Furthermore, Cairo suffers from serious
problems that prevent the development of productive activities. The fast-growing population and the failing
government approaches to housing and spatial planning policies contributed to the growth off informal
settlements within and around the center. At least seven million Egyptian, live in informal settlements in
Cairo with problems of unemployment, pollution, transportation, inadequate drainage and sewerage, and
lack of usable urban open spaces. In Cairo, the amount of green space per inhabitant is roughly equivalent
to 0.33 square meters per person (3.5 square feet), one of the lowest proportions in the world. Among the
above listed problems stands out a common denominator. It is the building roof or the so called ‘fifth
facade’. However, the problem with the green roofs project is lack of information and lack of know-how.
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Objective:
The purpose of this research is to establish a theoretical framework to implement green roofs in Cairo, as a
holistic approach for healthy productive cities. Green roof farming increases the availability of fresh and
high quality vegetables, encourage a more efficient use of water, and possibly create a source of income
for housewives. It depends basically on planting fruits and vegetables without wasting excess water or
using soil. The idea of planting rooftops can be carried out on a very small scale; it is easy-to-do and
available to anyone. What is required is to clear rooftops of any junk or garbage that might block sunlight.
As a result, the research aims to present a set of design principles, guidelines and tools that can assist in
transforming existing roofs into productive roof farms. In addition to successful case studies that introduces
a broader function of roof gardens, as well as the barriers for successful implementation.
Methodology:
Therefore, the first part of the study, presents the theoretical framework for roof farming. The study will
analyze, and map potentials and problems of green roofs are in a multilayered method. The goal is to find
out what the maximum potentials of productive green rooftops and determine the best techniques for
maintaining them. The second part of the study examines successful case studies in Cairo, including
schools and residential units and introduces a broader function of roof gardens, as well as the barriers for
successful implementation. Information from interviews, focus groups, and written reports will be analyzed
and aggregated according to success of the project.
Part 1: Green Roofs - Theoretical Framework and Analysis
Cairo, the capital of Egypt, is situated in a place where it controls the junction between Lower Egypt,
represented in the Delta, and Upper Egypt represented in the narrow Nile Valley. It is part of the mid-
latitude global desert zone and has similar climate to Phoenix, USA. Cairo is considered as one of the
world mega cities with at least 18 million inhabitants. The weather patterns in Cairo are characterized by
being extremely hot and dry (Group B, according to Köppen Classification). Average annual precipitation is
11mm; average daily temperature during July is 35.4oC; summer temperatures above 40oC are not
uncommon and often temperatures rise above 39oC. Average summer relative humidity is 62%.
Pollution
Cairo has to bear some of the worst air pollution in the world. The air pollution in Cairo is a matter of
serious concern. The air quality in downtown Cairo is more than 10 to 100 folds of acceptable world
standards. Air pollutants that are very high are particulate, hydrocarbons and lead. All are cancer causing
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agents. Moreover, Cairo has had to suffer the dreaded "black cloud" which for over ten years has
descended upon the city for a number of weeks, every autumn. Pollution in Cairo is expanding daily,
impacting the lives of countless millions of people for whom a breath of clean air has become an
unimaginable luxury.
Improved Air Quality
Plants work as an effective pollution filter. A green roof will not only absorb heat, but will also filter the air
moving across it. According to greenbacks from urban roof farming, it effectively removes as much as 95
percent of heavy metals such as cadmium, copper, and lead from runoff. Additionally, rooftop plants can
contribute to improving urban air quality by trapping and absorbing nitrous oxides, volatile organic
compounds, and airborne particulate matter.
Desert wind
The Khamasin winds are a series of dust and sandstorms which sweep North Africa between late February
and late May every year. In Europe this hot wind is called the sirocco. Cairo witnessed several Khamasin
sandstorms which shrouded the city in a thick yellowish haze. Hot Khamasin storms are characterized by
depositing dust and sand over Cairo during the spring season. This wind usually reaches high speeds and
brings with it big quantities of dust and sand. This wind is responsible for people's and animals` illness, for
the houses destructions and crops` damages.
Social Economic Benefit
Roof farming can provide a good opportunity for housewives and youth to increase their income, improve
the quality of their lives and contribute in improving the environment around them. In fact, social benefits
that have emerged from urban roof farming practices are; better health and nutrition, increased income,
employment, food security within the household, and community social life. In Cairo the urban roof farming
was quite efficient and helped women find work, who in some cases are marginalized from finding
employment in the formal economy.
Heat Island Effect
Heat island effects can be mitigated through the application of shading and the use of materials that reflect
the sun’s heat instead of absorbing it. In Egypt, where hot climate prevails, proper green roof design can
reduce the heat gains of buildings. Vegetation can shade buildings and pavements from solar radiation and
cool air through evapotranspiration. Designing vegetated surfaces, through selective distribution and layout
of vegetation patterns and types on the urban-scape and maximizing the area for planted or “green” roof
gardens (i.e. vegetables or other vegetative matter), helps reduce the heat island effect. Thus, planting
rooftops is one of the ways by which we can reduce the heat island effect. In fact, vegetation is invaluable
for improving the climate in hot regions.
Moderation of Heat Island Effect
The dense urban planning patterns and non-reflective surfaces for buildings and roads contributes to heat
island effects created when radiation from the sun is absorbed and transferred through convection and
conduction back to surrounding areas. As a result of heat island effects, ambient temperatures in Cairo can
be artificially elevated by more than 5-degree C when compared with surrounding suburban and
undeveloped areas. Another important phenomenon that occurs in the winter is the inversed green house
effect. Pollution trails prevent solar rays from reaching the ground, thereby masking the true temperature
increase. Atmospheric pollution blocks the rays, and therefore prevents the rise in temperatures.
High Energy Consumption
The building skin including the roof is very important because it has a direct impact on thermal comfort and
energy conservation in and around buildings. As a result of heat island effects, ambient temperatures in
Cairo can be artificially elevated by more than 5-degree C when compared with surrounding suburban and
undeveloped areas. This results in increased cooling loads in the summer, requiring larger AC and HVAC
equipment and electrical demand resulting in more greenhouse has and pollution generation, and
increased energy consumption for building operations.
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Saving on Cooling Energy
In Egypt, where hot climate prevails, proper green roof design can reduce the heat gains of buildings.
Planting rooftops provide good shading that can keep temperature comfortable in the upper floor. It can
also save energy by reducing or eliminating the need for artificial air- conditioning. Planting roofs can work
to cool buildings by insulating the uppermost floors in a building. Usually, the temperature in the upper
floors is higher than that in the lower ones. This is due to being subjected to direct sunrays all day long,
especially in summer. Thus, the direct solar- heat absorption of the roof in the top most floors needs to be
considered.
Dense Urbanization
Cairo is so vast and so dense; concrete and brick buildings and neighborhoods stretch out as far as the
eye can see, only disappearing into the hazy horizon or the edge of the desert. Within the city's boundaries,
the population density average 26,000 people per square kilometer. In some of the more crowded quarters
of the city, such as Dar al salam, densities are as high as 135,000 per square kilometer. Additionally, the
city compounds the existing problems of unemployment and scarce housing. Also, Cairo is one of the
densest and most open space deprived cities in the world, where open space per capita is measured in
square centimeters. Cairo is a city where the only large green spaces belong to private clubs.
Green Open Space & Aesthetics
Urban roof greening has long been promoted as an easy and effective strategy for beautifying the built
environment and increasing investment opportunity. Green roofs can help to address the lack of green
space in many urban areas. Urban green roofs provides the city with open spaces that helps reduce urban
heat island effect and provides the human population on the site with a connection to the outdoors.
Trellises and other exterior structures can support vegetation to shade the roof. Trellis, pergolas, ramadas,
tents, canopies and other elements are also an essential design element for the building roof.
Health & Food Problems
Challenged by environmental and pollution, Egypt suffered lately from locally grown food, loaded with toxic
contaminants that threat the health. In the recent couple of years Egypt and especially Cairo suffered from
an inefficient production and food distribution and inaccessibly high food prices. Cairo citizens and some
governmental authorities acknowledge the problem of food contamination & distribution and are mapping
measures and methods that can guarantee safe food.
The soaring food and prices especially, bio-vegetables and fruits. The intensive use of pesticides and
preservatives in agriculture caused a huge demand on fresh and bio-vegetables and fruits and left the
capital with limited resources.
Urban Healthy Food Production
Access to nutritious food is an important issue to locate food and livestock production in cities. Using high-
density urban roof farming, many environmental benefits can be achieved on a city-wide scale that would
be impossible otherwise. These systems provide food, and can recycle organic waste back to energy and
nutrients. At the same time, they can reduce food-related transportation to a minimum while providing fresh
food for large communities in almost any climate.
Toolbox for Roof Design
There are many different methods to plant the roofs. In Egypt, soil-less agriculture is used to grow plants
on the roofs of the buildings. It is also known as “container gardening” and considered to be less formal
and cheaper than other methods. In container gardening, few to no modifications are made to existing roof
structures. Containers or anything from plastic swimming pools to recycled-wood planters- are placed on a
rooftop and filled with soil and plants.
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Thus, a simple, economical, and water saving technique is used. It aims at using water efficiently in a
“closed-system” using simple substrates. This system collects the water for irrigation in plastic buckets
where it can be reused later. The substrates that are used are available and easily found. As for the soil
used; there are two alternative types of soil which are:
(1) Peat moss (a form of algae)
(2) Perlite (a type of volcanic eruption that is treated at the temperature of 1000 degrees Celsius to form
granules suitable for use in agriculture).
Peat moss. Perlite, as well as rice husks and sand have the advantage that they don’t get infected with
what infects the normal soil, and thus there is no need for pesticides.
There is a more advanced method used at some places in Egypt, which is using a closed cycle including
fish farms next to the plant. This has the advantage of allowing the plant to benefit from the ammonia
excreted by the fish helping the plants to grow better and at the same time eliminating the need for
changing the water for the fish, because the plants help to keep it clean by absorbing the ammonia.
Additionally, the fish get some nutrients from the roots of the plants as well as the oxygen.
Plastic pipes used for creating a
closed system to irrigate plant without
wasting water
Using fish farms next to the
plant. Each benefit from the
other.
The closed system of pipes works as a
network
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Part 2: Green Roofs - Case Studies in Cairo
Rooftop planting- the Egyptian examples:
I the meantime in Egypt, population explosion and the tendency to build on agricultural land have acted to
limit the resources of city families and their access to health products. With a little effort and money,
rooftops can contribute in improving the family’s quality of life and provide them with healthy food and raise
their income, this is besides the environmental and aesthetical role it plays. While it is not new, the notion
of planting rooftops in Egypt has only recently been implemented. In the early 1990s at Ain Shams
University, a group of agriculture professors developed an initiative of growing organic vegetables to suit
densely populated cities of Egypt. The initiative was applied on a small scale; until it was officially adopted
in 2001, by the Food and Agriculture Organization (FAO). The following case studies represent successful
projects that were implemented by different non-governmental organizations (NGO), public institutions and
private civil initiatives.
Results:
The economical benefit and the expenses
One of the most important and great advantages of planting rooftops is its being an economical support for
families, as well as contributing to raising their income. The materials used, and the expenses should be
low as much as it could be.
As mentioned before, the systems used widely vary, and the expenses depend on the system used and
implemented. Expenses vary depending on the system used. The manual system consists of wooden
containers (barrels) with plastic sheets filled with peat moss or perlite used as substrates. The drainage is
driven through small plastic hoses to a bucket. This system is suitable for leafy crops such as parsley,
radish, and carrots. A square meter using this method would cost around 130 Egyptian pounds (LE)
($US20.5). The manual system is not used to generate a source of income. It is mainly for domestic
consumption of produce. The main element here is exposure to sunlight; no extra care is required.
If the project is established for the purpose of business, then wall gardens are a good choice. Wall gardens
consist of plastic tubes or bags hung on the roof's walls to hold the plants; irrigation and drainage are done
automatically. This way a larger area of the roof is used in contrast to the wooden containers used in the
manual system. This method is similar in cost to that of the manual system. A square meter will cost 150 to
170 LE (approximately $US 26). As for the method of farming fish next to the plant in a closed cycle, all
what is needed is the air and water pumps. The whole system including pumps costs LE 700-800 per 1x2
square meters.
Consideration for green roofs
When designing green roofs, attention must be given to support, waterproofing and drainage. The modular
Green roofs have more demanding structural standards. Some existing buildings cannot be retrofitted with
a green roof because of the weight load of the soil and vegetation. Depending on what kind of roof it is, the
maintenance costs could be higher.
(1) Social and Economic Benefits
It is important to realize that in Cairo, the urban roof farming can provide food in economically significant
quantities. Roof farming can provide a good opportunity for housewives and youth to increase their
income, improve the quality of their lives and contribute in improving the environment around them. It
allows for a healthy ecological balance and makes it possible to avoid costly and environmentally
destructive chemical inputs such as fertilizers, pesticides, or herbicides. Urban roof farming can be seen as
a means of improving the livelihood of people living in and around cities. Taking part in such practices is
seen mostly as informal activity, but in many cities where inadequate, unreliable, and irregular access to
food is an occurring problem, urban roof farming has been a positive response to tackling food concerns.
Households and small communities take advantage of it and contribute not only to their household food
needs but also the needs of their resident city. Community and residential roof farming, save household
food pounds. They promote nutrition and free cash for non-garden foods and other items. This allows
families to generate larger incomes selling to local grocers or to local outdoor markets, while supplying their
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household with proper nutrition of fresh and nutritional produce. In Cairo the urban roof farming was quite
efficient and helped women find work, who in some cases are marginalized from finding employment in the
formal economy. Urban roof farming will continue to help impoverished communities gain a better well-
being while fighting urban poverty.
Quality of Food
Access to nutritious food is an important issue to locate food and livestock production in cities. Using high-
density urban roof farming, many environmental benefits can be achieved on a city-wide scale that would
be impossible otherwise. These systems provide food, and can recycle organic waste back to energy and
nutrients. At the same time, they can reduce food-related transportation to a minimum while providing fresh
food for large communities in almost any climate.
(2) Environmentally
Plants help in cooling the surroundings on summer, giving residents a uniquely healthy space of their own.
On an appropriately wide scale, “roof planting” would significantly improve the environment. Not only does
it raise the oxygen level, but also it helps keep temperature low. What makes rooftop planting different and
considered to be of great advantage (from an environmental point of view) is its significant role in:
Improved Air Quality
Plants work as an effective pollution filter. A green roof will not only absorb heat, but will also filter the air
moving across it. According to greenbacks from urban roof farming, it effectively removes as much as 95
percent of heavy metals such as cadmium, copper, and lead from runoff. Additionally, rooftop plants can
contribute to improving urban air quality by trapping and absorbing nitrous oxides, volatile organic
compounds, and airborne particulate matter.
Moderation of Heat Island Effect
As Cairo grows and replaces natural settings it also relinquishes associated ecological services. Green
roofs cool the area surrounding it via shade and evapotranspiration. The dense urban planning patterns
and non-reflective surfaces for buildings and roads contributes to heat island effects created when radiation
from the sun is absorbed and transferred through convection and conduction back to surrounding areas. As
a result of heat island effects, ambient temperatures in Cairo can be artificially elevated by more than 5o C
when compared with surrounding suburban and undeveloped areas. This results in increased cooling loads
in the summer, requiring larger AC and HVAC equipment and electrical demand resulting in more
greenhouse has and pollution generation, and increased energy consumption for building operations. Heat
island effects can be mitigated through the application of shading and the use of materials that reflect the
sun’s heat instead of absorbing it. Therefore, green roofs are innovative in making the surrounding
environment more balanced. Vegetation can shade buildings and pavements from solar radiation and cool
air through evapotranspiration. Designing vegetated surfaces, through selective distribution and layout of
vegetation patterns and types on the urban-scape and maximizing the area for planted or “green” roof
gardens (i.e. vegetables or other vegetative matter), helps reduce the heat island effect. Thus, planting
rooftops is one of the ways by which we can reduce the heat island effect. In fact, vegetation is invaluable
for improving the climate in hot regions.
Another strategy to reduce the heat island effect is cool roofs. Studies have shown that white or lighter
color rooftops make a remarkable difference in terms of mitigating the heat island effect because they
reflect rather than absorb heat. Of essence, the provision of providing lighter color rooftops can be
achieved through planting the roofs with different kinds of crops and vegetations. Most traditional dark
colored roof surfaces absorb about 70 percent or more of the solar energy striking them, resulting in a peak
roof temperature of 65-88C. Cool roofs, on the other hand, which are roofs coated with light-colored
surface treatments, are 10-16C cooler on hot days. The resulting reductions in the transfer of heat into the
air-conditioned spaces below can decrease cooling costs by an average of 20 percent.
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Cooling Energy Savings
In Egypt, where hot climate prevails, proper green roof design can reduce the heat gains of buildings.
Planting rooftops provide good shading that can keep temperature comfortable in the upper floor. It can
also save energy by reducing or eliminating the need for artificial air- conditioning. Planting roofs can work
to cool buildings by insulating the uppermost floors in a building. Usually, the temperature in the upper
floors is higher than that in the lower ones. This is due to being subjected to direct sunrays all day long,
especially in summer. Thus, the direct solar- heat absorption of the roof in the top most floors needs to be
considered.
(3) Aesthetical & Spatial
Urban roof greening has long been promoted as an easy and effective strategy for beautifying the built
environment and increasing investment opportunity. Green roofs can help to address the lack of green
space in many urban areas. Urban green roofs provide the city with open spaces that helps reduce urban
heat island effect and provides the human population on the site with a connection to the outdoors.
Outdoor spaces and structures
The building roof is very important because it has a direct impact on thermal comfort and energy
conservation in and around buildings. This zone includes elements such as screens, light structures,
rooftop greening, and grass. Akbari proofed that urban vegetation reduces the energy needed for indoor
climate control (Akbari, Kurn et al. 1997). Trellises and other exterior structures can support vegetation to
shade the roof. Trellis, pergolas, ramadas, tents, canopies and other elements are also an essential design
element for the building roof. In general, large paved areas should be broken up with shaded areas or with
zones of vegetation and ground cover (Reynolds 2002). Habitable roofs can also be used in conjunction
with vegetated ones (Attia 2006 ).
Conclusion
Financial and Technical Feasibility
This study showed that one of the most important and great advantages of planting rooftops is its being an
economical support for families, as well as contributing to raising their income. The materials used, and the
expenses are considerably low. The systems used widely vary, and the expenses depend on the system
used and implemented. The manual system consists of wooden containers (barrels) with plastic sheets
filled with peat moss or perlite used as substrates. The drainage is driven through small plastic hoses to a
bucket. This system is suitable for leafy crops such as parsley, radish, and carrots. A square meter using
this method would cost around 30 US dollars. The manual system is not used to generate a source of
income. It is mainly for domestic consumption of produce. The main element here is exposure to sunlight;
no extra care is required. If the project is established for the purpose of business, then wall gardens are a
good choice. Wall gardens consist of plastic tubes or bags hung on the roof's walls to hold the plants;
irrigation and drainage are done automatically. This way a larger area of the roof is used in contrast to the
wooden containers used in the manual system. This method is similar in cost to that of the manual system.
A square meter will cost 35 US dollars. In fact, based on the square meter pricing both systems are cost-
effective.
A Look into the Future
In the city of Cairo, where many environmental social and economical problems exist, and others related to
the unawareness with concepts of energy consumption and sustainability, a beam of light emerges to
contribute in solving many of these interrelated problems. Planting our roof with different kinds of
vegetables and fruits or even any kind of green plants will change lots of things. It is certain that roof
gardening have measurable qualitative and quantitative benefits. The techniques for implementation are
simple and doable and above all cost efficient. However, no roof gardens can be created without the
knowledge of the factors affecting the creation and design. The most important factors are the climate, the
constructional and economical factors. More importantly, a vision is required to be drawn together with long
term strategy, adopting the holistic approach of green roofs and providing support and sustainability. It is
this holistic approach that can solve many problems of different background and aspects, and can
Proceedings of 7th Annual Greening Rooftops for Sustainable Communities,2009, Atlanta, USA
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contribute to improving the quality of life of the Egyptian community. By exploitation of such roofs, their
development and planting; a reasonable ratio of green areas can be reached in the near future. A ratio of 4
square meters per person can be provided once the suitable green framing roofs have been developed and
exploited.
References:
This paper describes the idea of green roofs as a holistic approach to solve environmental, spatial, social and
economic problems in Cairo. This paper examines succesful case studies in Cairo and introduces a broader
function of roof gardens, as well as the barriers for successful implementation.
Abdel-Moneim, A. (2005). May your roof be green. Al-Ahram. Cairo, AL-Ahram. 745.
Akbari, H., D. Kurn, et al. (1997). "Peak power and cooling energy savings of shade trees." Energy and Building 25(2):
139-148.
Attia, S. (2006). The role of landscape design in improving the micro-climate in traditional courtyard buildings in hot arid
climates. PLEA Geneva, Switzerland. .
Corbett, J., M. N. Corbett, et al. (2000). Designing sustainable communities : learning from Village Homes. Washington,
D.C., Island Press.
FAO. (2006). "Eco-friendly roof gardens of Egypt." Retrieved November, 2008, from
http://www.fao.org/getinvolved/telefood/telefood-projects/slideshows/eco-friendly-roof-gardens-of-egypt/en/.
Johansson, A. (2002). Roof Gardens in New York City. Landscape Planning. Alnarp, Swedish University of
Agricultural Sciences. Master.
Reynolds, J. (2002). Courtyards : aesthetic, social, and thermal delight. . New York John Wiley.
Yannas, S., E. Erell, et al. (2006). Roof cooling techniques: a design handbook. London ; Sterling, VA, Earthscan.
Yeang, K. (2006). Ecodesign : a manual for ecological design. London, Wiley.
Bio of the Authors:
Shady Attia is an Egyptian architect graduated from the Faculty of Fine Arts, Helwan University, Cairo,
Egypt, in 2002. His research interest is focused on Bioclimatic Landscape Design in hot climates. He
worked for three years as a professional architect at El Ghazali and CDC-Abdelhalim Architecture firms.
Between 2004 and 2006 he completed his Master thesis at the Landscape Architecture Group,
Wageningen University in the Netherlands. After one year at Texas A&M University, he decided to pursue
his PhD research at the Architecture and Climate Unit at the Université Catholique de Louvain, in Belgium.
Alia Amer is an Egyptian architect graduated from the Faculty of Fine Arts, Helwan University, Cairo, Egypt,
in 2006. Her research interest is focused on productive and healthy cities. She participated in several
workshops about Green in Cairo. Since 2006, she is working as Teaching and Research Assistant at the
Architecture Department, Faculty of Fine Arts of Helwan University.
... Ce système est complètement ancré dans les pratiques alimentaires, étant donné sa généralisation à la majorité de la population et le fait qu'il permette un accès aux produits situation de crise alimentaire et de « réduction de la production alimentaire » (Ayeb, 2008 (en utilisant le pain comme de la nourriture pour les animaux et les poissons ou en vendant la frite et le pain sur le marché noir). » (Ecker, Al Riffai, 2016, p. 57-58 Vancouver, New York ou Berlin, pour mettre en évidence les avantages à produire en ville (Gawad, 2014 ;Attia, Mahmud, 2006 Il s'agit donc d'une littérature à la fois institutionnelle et académique, ou plus souvent résultant de l'imbrication de ces deux milieux, qui met en avant l'agriculture urbaine comme pouvant être une réponse à de nombreux enjeux au Caire. Une partie de ces études prend tout de même en compte les limites qui peuvent intervenir dans la mise en place de ces structures productives sur les toits, notamment des problèmes de reconnaissance légale, de droit de propriété ou encore d'irrigation et de résistance à la chaleur. ...
Thesis
Rooftop farming in the district of Matariya and rural allotments on Dahab Island in Cairo represent two contrasting instances of urban agriculture, which are nonetheless characterized by similar issues. In a context of land reforms in informal spaces, environmental and social concerns, supported by notable international and institutional stakeholders, have dominated the discourse in comparison to a potential enhancement of the productive and nutritional function of these spaces. Examples of urban agriculture studied by the author, which are inadequate to solve the food security in Egypt, are at the center of territorial development projects, promoted by external actors and seized by local ones. Their relationship with the government, which is more or less contentious depending on the compatibility of their activity with urban strategies defined at a national scale, substantially determines the organization of farming spaces in Cairo. Identity, property and metropolitan issues are incorporated into debates on urban agriculture’s function and on the integration of these productive activities to Cairo’s food systems.
Conference Paper
Full-text available
Arab Islamic landscape design forms a unique source of inspiration for landscape architecture in barren open spaces in the Middle East. Arab Islamic gardens adopted a system marked by perfect responsiveness to the environment. The design of urban landscapes and gardens in Arab Islamic culture was similarly guided by the dictation of aridity. The need to provide shade, to prevent dust and to conserve water meant that urban open spaces and gardens were sheltered and enclosed. Alhambra in Moorish Spain and the Al-Suhaymi House in Islamic Cairo are two useful historical references for vernacular Islamic landscape designs. This paper presents an overview of landscape design considerations for the composition of vegetation and water and initial observations of their influence in controlling and improving the microclimate in courtyard buildings as a way of passive cooling in the Middle East region. This paper is a part of a Master's thesis in the field of passive landscape strategies at Wageningen University. The objective is to identify the comfort improvements potential of successfully-planned and integrated landscape design in traditional courtyard buildings. The layout and plant material of Alhambra, Generalife courts and Al-Suhaymi court in Islamic Cairo are examined and evaluated. This study demonstrates that in arid environments, the landscape planning, the composition of vegetation and water and choice of planting material all have important consequences in creating thermally-pleasant environments.
Article
In summer of 1992, we monitored peak power and cooling energy savings from shade trees in two houses in Sacramento, CA. The collected data include air-conditioning electricity use, indoor and outdoor dry bulb temperatures and humidities, roof and ceiling surface temperatures, inside and outside wall temperatures, insolation, and wind speed and direction. Shade trees at the two monitored houses yielded seasonal cooling energy savings of 30%, corresponding to an average daily savings of 3.6 and 4.8 kWh/d. Peak demand savings for the same houses were 0.6 and 0.8 kW (about 27% savings in one house and 42% in the other). The monitored houses were modeled with the DOE-2.1E simulation program. The simulation results underestimated the cooling energy savings and peak power reductions by as much as twofold.
Article
This study is about roof gardens in New York City. The purpose of the project was to study the design of roof gardens in a place where these have a long tradition. The central issue was to find and present the gardens and to apply some design ideas on a small roof terrace in Gothenburg, Sweden. My hope was to find traditional landscape architecture proved to be working in the course of time and breathtaking contemporary design ideas to be inspired by. The study was made during a two-month stay in New York City in April and May 2001. All the studied gardens are located on Manhattan. The Gothenburg terrace was designed in Fall 2001. Different kinds of roof gardens are studied: public parks, museum gardens, schoolyards, public plazas, corporate gardens, a healing garden, shared private gardens and one-family residential gardens. Complementary information was searched in literature, in periodicals and on the Internet. The text is divided into two main parts. The first part, called Field Study, is a report from the study of roof gardens on Manhattan, New York City. The design and impression of 39 gardens are each presented in words, and illustrated by photos and a watercolor sketch of the lay out. The second part, called Case Study, is about the roof garden in Gothenburg,Sweden. It is designed with the New York experience in recent mind. This part consists of a short presentation of the present terrace and its owner and my thoughts as well as a plan and description of the proposal. I want to create a modern easily maintained terrace with a romantic touch. The garden has a frame work of whitened oak wood and the plant material has warm colors, a wish of the owner.
May your roof be green
  • A Abdel-Moneim
Abdel-Moneim, A. (2005). May your roof be green. Al-Ahram. Cairo, AL-Ahram. 745.
Courtyards : aesthetic, social, and thermal delight
  • J Reynolds
Reynolds, J. (2002). Courtyards : aesthetic, social, and thermal delight.. New York John Wiley.