Inefficient use of biomass for heat production in non-centrally supplied households is a serious problem. The project “Changing biomass-inefficient boilers in households” aims to reduce this problem. The aim of the project is to increase energy efficiency in households. The objective of the project is to encourage households to replace individual boilers using biomass inefficiently into more efficient technologies (heat pumps, biofuel pellet boilers corresponding to class 5), thus reducing primary energy consumption for heat production and hot water production, in households that are not connected to the district heating system. The main result of the project is to reduce energy consumption in households (not connected to district heating networks) by replacing inefficient biofuel boilers into more efficient renewable energy technologies, reducing energy consumption in households (not connected to district heating networks), and reducing air pollution (reduced emissions of particulate matter due to less biofuel consumption).