Energy savings are achieved as a rule by reducing expenditure on heating, ventilation , possibly air conditioning and lighting. This in the long run may have a negative impact on man. If the temperature is very low exposure to cold may occur or eyesight may be damaged by permanent stay underground, the quality of indoor air may deteriorate if the peripheral walls of a building are too tight and all this may have a significant negative effect on the mental and physical efficiency of man exposed to the wrong temperature and humidity of the atmosphere and inadequate lighting.

        Key words: energy savings - impact on health - indoor temperature - ventilation - air humidity - lighting