The household in Latvia is the most energy capacious sector – 40 % of the final total energy consumption has been consumed by household in 2007. According to that the energy demands in household as well as energy conservation potential are very important parts of the management and development of energy sector. Energy demand and also efficiency in housing sector generally depends on various circumstances: social sphere and state or municipal regulations, infrastructure of living area and energy supply, building envelope conditions, population’s consumption habits, thinking manner (ownership) and climate conditions. Heat energy saving arrangements is the main for the refurbishment of prefabricated housing because thermal insulation is paramount to both heat energy savings and to repairing facade damage. The advantages of heat energy saving measures, particularly with respect to prefabricated housing, are undeniably evident: • Reducing heat energy consumption by 40 to 50% is easily attained. These reductions are equal in an average reduction of the total energy consumption to 60 kWh - 80 kWh per squire meter of heated floor area per year. • A thermally insulated facade results in dry, warm exterior walls and stops weathering damage to the facade. The paper presents potential for energy saving in building sector in Latvia and the results from the realized projects of building refurbishment when building envelope element U-values have been reduced significantly by external insulation measures, and internal heating system have been rebuild. The projects illustrate the typical housing energy consumption and optimal energy saving measures for different types of buildings.