Abstract:
Since the last few decades the world population has been increasing in a faster rate. With the
increasing population, the needs of the people have also increased. Because of that more people
have lean towards to move to the cities in search of facilities. The demand for dwellings in the
cities has increased. To accommodate this demand, more buildings have been constructed,
changing the previous arrangement of the cities. The cities have turned into a compacted space
with less vegetation and greenery. Yet again the pervious lands in the urban space have changed
to impervious surfaces making the urban climate to be changed peculiarly in terms of
temperature and air quality. The more the urban space has become industrialized, the more the
air has been contaminated. There are other environmental issues together with the changes for
the cities. Due to the increment of artificial surfaces the temperatures of the cities have been
increased than the country side allowing the heat island effect to take place making the energy
demands of the cities to be high. For these climatic problems the researchers have identified
green roofs as a sustainable solution.
This research mainly focuses on augmentation of air quality and on reduction of heat island
effect, with the replacement of existing flat slabs in the Colombo city in Sri Lanka, with green
roofs. A well compacted city area was chosen in the Colombo district. The measurements were
taken in terms of temperature and C02 in the chosen city area and in countryside. Different
special places were chosen for the measurements. The obtained measurements are observed for
the identification of the best remedy. With that the expected increment of air quality and
expected reduction of the temperatures are modeled with the replacement of existing flat slabs
in the area with green roofs. A comparison was done on the actual measurements found in the
present situation, with the results obtained from the modeled situation. From the results it's
evident that the green roofs can play a major role in enhancing air quality and reducing heat
island effect making people to live in cities comfortably and healthily.
