Building solutions for improving energy efficiency
1st TECHNICAL HIGH SCHOOL (EPAL) of Kessariani The 1st TECHNICAL HIGH SCHOOL (EPAL) of Kessariani, located at the North-East of the centre of Athens and next to the mountain of Imittos, at a highly dense urban area in the Greek capital, has been chosen mainly because of its energy consumption measured, but also because of the difficulties and - or possibilities for retrofitting and improving its energy efficiency. Being a typical public school building, built and managed by the Greek School Building Organisation, we assume that many of the problems found at the particular school will be common for other schools as well, and therefore, many proposed solutions will be suitable to solve similar problems. Thus the particular school, in our opinion, will successfully be a pilot case. The school is located in a typical middle to low incomes urban area of Athens, rather dense, with 6-7 storeys residential buildings. The main difference and big advantage -or disadvantage- of the particular school, is that it is located at the foot of Imittos Mountain, next to an extremely valuable and highly visited and popular park – the park of Kessariani, which provides good ventilation and fresh air to the entire neighbourhood, keeping temperatures almost 2 degrees lower during the hot summer days. The climate is typical in Athens and the greater Attica region, and it is characterised by mild winters and hot dry summers. Throughout the year, temperatures average at: summer 32º Celsius autumn 23º Celsius winter 12º Celsius and spring 20º Celsius Rainfall is mainly during the winter and annual rainfall levels are not high. The main problems identified at the school were focused on the building’s envelope. High energy consumption and indoor
discomfort, occurred originally by the disadvantaged orientation of the building, position to the site and architectural arrangement of the classrooms, which are mainly facing towards the North, having almost no openings towards the South, and therefore no solar heat gains, no cross ventilation and bad lighting conditions (at the biggest part of the building). The proposed solutions considered especially these aspects, and focused on a better arrangement and management of classrooms’ and public spaces’ openings. Other problems identified at the school had to do with the “heated areas” map of the building, found that open air spaces were heated while obviously this was not at all needed. Finally, major problems causing energy consumption had to do with heat losses through badly or non-insulated surfaces. The main measures proposed were costevaluated, as low, medium and high cost, and their effectiveness according to the relative cost. In order to be realistic, and taking under consideration the fact of the economic crisis that the country is going through, the measures proposed to be taken are rather the ones that fall under the low or medium cost categories. In the particular school, the measures proposed are the following: a. Insulation of external walls b. Creation of new openings, towards the South, were this is feasible, in order to assure better cross ventilation to as many
c. d. e. f. g. h.
classrooms as possible. Redesigning of the -South oriented- big skylight. Replacement of glass-blocks with flap opening windows Creation of green roof surfaces Installation of curtains or blinds at certain windows facing East or West Focusing on natural ventilation and preventing from the greenhouse effect Installation of ceiling fans Redesigning the “heated areas” map of the building, by reducing the thermal load as possible. Replacement of existing heating system with an autonomous system by wing and by floor, fitted with thermostats Integrated management and control Possibilities regarding the future of this school building are highly appreciated, given the fact that energy consumption and indoor comfort will be radically improved. Certainly, the best part of this work is the knowledge gained in designing ecological buildings in the future and retrofitting the existing ones.