Heating Calculations R Value Wall R Value Please Select Tent Brick- Uninsulated Brick- Light Insulated Brick- Well Insulated Wood- Uninsulated Wood- Light Insulated Wood- Well Insulated Metal- Uninsulated Metal-Light Insulated Metal- Well Insulated Manual Ceiling R Value Please Select Tent Brick- Uninsulated Brick- Light Insulated Brick- Well Insulated Wood- Uninsulated Wood- Light Insulated Wood- Well Insulated Metal- Uninsulated Metal-Light Insulated Metal- Well Insulated Manual Floor R Value Please Select Rock Soil Concrete Structure Length (ft) Structure Width (ft) Wall Height (ft) Peak Height (ft) Ambient Temperature (F) Ground Temperature (F) Desired Internal Temperature (F) Number of People Wattage of Lighting (W) Wall Calculations Required BTU's Ceiling Calculations Required BTU's Floor Load Required BTU's Additional Load Calculations Required BTU's Total BTU's Required kW of Heat This formula assumes return air. If return air is not used kW required must be doubled.