i have owned a 1976 northlander 60ftx12ft home here in toronto canada for 6 years now. replaced all my windows and rebuilt my bathroom 4 years ago, best investement i made. cut my heating bills by one tank of oil per season. and any body that knows canada we get pretty cool in our winters.my problem is heating , most of my heat goes out through the walls(only 2x3 studs with little insulation)and the roof. does any body know a way i can save more heat without a large output of money(now retired) any sugestion will be concidered.