Consideration should also take the state of affairs, that the building is unlikely to improve their thermal parameters, and sometimes needs increasing amounts of heat energy, to keep the temperature the same as a few years ago .
Maanani pia wanapaswa kuchukua hali ya mambo, kwamba jengo ni uwezekano wa kuboresha zao vigezo mafuta, na wakati mwingine anahitaji kuongeza kiasi cha nishati ya joto, kuweka joto sawa kama miaka michache iliyopita .