When looking for a new hearth product, like a fireplace, gas logs, or log sets, you may spot an efficiency rating. In the U.S., they offer the Annual Fuel Utilization Efficiency (AFUE) and Steady State ratings. AFUE ratings measures the percent of heat produced for the amount of fuel consumed. While typically used to indicate energy efficient appliances like furnaces, you may find an AFUE rating used for some fireplaces. Steady State measures how efficiently a fireplace converts fuel to heat once warmed and operating in a constant, or steady, state. In Canada, they offer the EnerGuide rating which measures annual Fireplace Efficiency (FE). This voluntary rating considers the performance and unit’s use throughout the heating season. According to the Government of Canada, most gas fireplace models on the market offer FEs between 30-70% with higher numbers offering better efficiency.