Transformation through renovation: An energy efficient retrofit of an apartment building in Athens

A 7 story social housing apartment building in Athens, Greece has been renovated following a holistic energy efficient retrofit process. The retrofit plan, resulting from tenant surveys, environmental parameters monitoring and extensive energy simulations, included commercially available technologies like insulation and energy efficient windows, innovative technologies like energy efficient lighting and smart coatings, passive techniques like night ventilation as well as RES, aiming to transform this inefficient building into a near zero energy one, achieving a reduction of the energy consumption and CO2 emissions by 80% and significant improvement of thermal comfort conditions. An experimental campaign has been executed in order to measure and validate the energy savings and indoor comfort conditions before and after the retrofit. The results of this monitoring procedure are reported and analyzed. Measurements include air leakage and thermal imaging for determining leakage rate and heat loss through the building fabric, smart meters to record energy consumption and indoor and outdoor environmental measurements. The opinion of the occupants is taken into account through pre- and post-retrofit surveys. (C) 2017 The Authors. Published by Elsevier