Abstract
Low-income households in developed and less developed countries suffer from serious indoor environmental problems such as heat stress, lack
of comfort and poor indoor air quality. Passive cooling of buildings and in particular solar and heat protection techniques, heat dissipation and heat
amortisation techniques have reached a very high degree of maturity. New technological developments have proven extremely efficient in
decreasing the need for cooling and improving indoor environmental conditions. Developments on the field of solar and heat protection, such as
highly reflective coatings for the urban environment and the building envelope and new knowledge and developments on the field of ground and
convective cooling and ventilation,may help low-income citizens to considerably improve their quality of life during the overheating period. These
new developments are characterised by low cost and are easy to apply.
This paper investigates the potential of the more promising new 本文来自辣)文,论(文'网，毕业论文 www.751com.cn 加7位QQ324_9114找源文 -income households in warm areas of the planet, ground cooling using earth to air heat exchangers,
and discusses the potential of new ventilation techniques and systems for improving indoor comfort and air quality. Results show a very high
potential to improve indoor environmental conditions and contribute towards higher passive survivability levels.
# 2007 Elsevier B.V. All rights reserved.
1. Introduction
Buildings are the major economic sector in theworld and the
quality of buildings, shapes the life of citizens. Although there
is an important increase of the budget devoted to construction,
the United Nations estimates [1], that more than one billion
urban citizens, live in inappropriate houses – mostly in squatter
and slum settlements – while in most of cities in less developed
countries between one- and two-thirds of the population live in
poor quality and overcrowded housing [2,3].
Even in the developed world the percentage of people
living in low-income households is quite high. The average
percentage of low-income households in the EU is close to
15%, while in some countries like Ireland it may go up to 21%
[4].
Inappropriate housing is characterised by poor indoor
environmental conditions such as extremely low or high
temperatures, lack of ventilation, etc. In parallel, heat island
conditions in dense urban areas increase ambient temperatures
and the thermal stress to buildings, especially during the
summer period [5]. For example, in Athens the heat island
increases the cooling load of buildings by about 100% [6], and
the heat island ismainly present in city areas where low-income
people are living [7].
A research that was carried out in 1100 households in Athens
[8], has shown that low-income people live in old construction
buildings. The mean age of households of the lower income
group is 29 years while for the richest group it is 19 years. In
parallel, a very clear relation is found between the income level
and the quality of the envelope. Only 28% of people in the low-
income group live in insulated buildings, while the correspond-
ing figure for the high-income group is close to 70%. In parallel,
it is found that the higher the income the higher the percentage
of buildings with double glazing. For the poorest group the
percentage of double glazed buildings is 24% while for the