<p>System of prefabricated modules installed on the existing building envelope is one alternativesolution for deep energy refurbishment of buildings in the European Union. It allows thermalupgrade installation of new parts in the HVAC system. Moreover, some elements of the envelopecan be made of renewable materials. This research compares the residential building stock andidentifies potential types of buildings for energy refurbishment in Bosnia and Herzegovina andSlovenia. It presents refurbishment possibilities of existing residential building stock in bothcountries with prefabricated timber panels. It also presents potential obstacles to the widerapplication of this refurbishment solution.</p>