Energy Efficient Retrofit of Existing Public Glass Buildings’ Façade: Case Study a Building in Istanbul Technical University

The upcoming energy efficiency directive would introduce mandatory measures such as renovate 3% of the total floor area of public buildings with a total floor area of more than 500 m², and as from July 2015, of more than 250 m² and also the latest directive on Energy Performance of Buildings (EPBD) insists on energy efficient renovation of existing buildings. It is clear that millions of jobs will be created while the energy bill and climate pollution would be declined if those decisions implemented aright. These issues indicate the importance of energy efficient retrofitting of existing buildings. In office buildings, not only heating, cooling and ventilation consume a lot of energy but also lighting is account for huge amount of energy consumption on the other words, while HVAC system of an office building is being retrofitted, lighting system should be under consideration as well due to possible parallel or negative results. Initial survey about a building in Istanbul Technical University's campus cleared that thermal discomfort and glare problem are disturbing occupant during the summer period; hence, some packages define to investigation and initial results illustrated that it is possible to reduce HVAC energy consumption of building about 30 percent where lighting energy consumption increases approximately 12 percent. By comparing the cost related to each retrofit package and energy saving, the final decision can be made and without this compare any decision can be blundered. For instance, our investigation illustrated that some packages that provide energy saving can be inappropriate for a specific period.