I am new to this forum and I haven't used a woodstove in about 20 years. We recently installed a Progress Hybrid and I am trying to figure out how much wood I will need to heat with. We normally use about 750 gallons of propane per year which equates to 68,497,500 btu's of heat. I mainly have red oak which is about 21,000,000 btu's per cord. Using these numbers I need about 3.25 cords of wood to heat the house. I'm sure I need some 'extra' wood just in case. Any ideas how much? FYI, our house is a 2,400 sq. ft. ranch with 8 foot ceilings. The woodstove is located centrally in the house. Thanks for your help and input!