For that reason, several projects and researches are carried out in the EU to study the balance between energy efficiency, thermal comfort and conservation requirements in order to involve the historic building stock such as 3ENCULT, EFFESUS projects \citep{dubois2016comfort}. Another example, the results of studies have been carried out in Sweden to balance between the energy conservation and building conservation showed that 20% of energy saving can be achieved without damaging the cultural heritage value \citep{_ahin_2015}.
In Egypt, building sector consumes about 42% of energy \citep{Fahmy_2014}. The Egyptian building stock comprises about 12 million buildings, 60% of these buildings are in the residential sector \citep{hanna2013sustainable}. Thus, the exiting residential sector is the major consumer of energy in Egypt. Since Egypt is located in a hot arid climate zone, it depends on electricity as a main energy source for running the HVAC systems \citep{Friess_2017}. The residential sector consumes around 43.4% of the total electricity consumption comparing with other sectors as shown in figure (12) \citep{Radwan_2016}.