We aimed to study the CO2 emissions of detached houses using firewood for heating, using the example of a Hungarian village (Milota). We presented Hungary’s CO2 emission structure and discussed the increasing ratio of firewood heating in households in relation to the increasing level of poverty in the population and the increasing price of natural gas. The annual firewood consumption of 22 households in an eastern Hungarian village in a rural environment was measured and the associated CO2 emissions were calculated. We found that the material of the walls was relevant; however, age structure was not important in the volume of the burnt firewood. Outdoor temperature determined significantly the amount of combusted wood and the analyses also revealed that heating habits (considering the daily routines of weekdays and weekends) can also influence CO2 emissions. It is argued that using firewood for heating is beneficial at both local and national levels since the absorption capacity of forests in Hungary can keep pace with firewood combustion emissions; although, they can absorb only 48.6% of total household CO2 emissions. At a global level, however, firewood combustion increases the CO2 content of the atmosphere.