This work presents methodology and the Case study about energy savings and improvement of indoor comfort at hospitals. There are two major aspects for energy saving in the health care sector. First is the potential for the savings via the combination of engineering tools: Improving the buildings insulation and ventilation systems; recovery of heat from ventilation systems and warm waste water; improvement of electrical systems; changes in user behaviours. The other is improvement of indoor comfort in the buildings with a high level of hygiene requirements. Case analysis has been performed...