Space Heating Calculator Use this tool to calculate the values for heat lost, startup power, and total heating required. Space Dimensions Length: m Width: m Height: m Temperature Change Outside Temperature: °C Inside Temperature: °C Surface Heat Loss Properties If you would like to calculate additional Surface Heat Loss items, please add them here. Alternatively, you can skip straight to Air Changes field. Name: Area: m² Temp Delta: °C U Factor: W/m²°C Heat Loss: kW Air Changes Air Changes: per hour Result Surface Heat Loss: kW Air Change Heat Loss: kW Startup: kW Total Heating Required: kW