The goal of this study was to conduct a comparative evaluation of two heating systems in terms of energy efficiency as well as effect on barn environmental conditions and hog performance. An infrared radiant heater and a forced-air convection heater were installed separately in two grow-finish rooms at the Prairie Swine Centre Inc (PSCI) research facility. Consumption of natural gas and electrical energy were monitored in each room, as well as air temperature, relative humidity, and ventilation rate. Additionally, gas sensors were installed to monitor hydrogen sulfide (H₂S), ammonia (NH₃), carbon monoxide (CO) and carbon dioxide (CO₂) concentrations in the rooms. The results from three completed trials showed that the room with infrared radiant heating system consumed more natural gas but less electrical energy compared to the room with forced-air convection heater. Mean air temperature was higher in the room with forced-convection heater than in the room with radiant heater, but air temperature distribution at various locations within each room was similar. Generally, the relative humidity, ventilation rate, gas concentrations (NH₃, H₂S, CO and CO₂), and pig performance were relatively similar between the rooms, indicating no significant impact of the type of heater on these parameters.