We had an extended holiday travel this year. I intentionally left some snow cover on my greenhouse roof to slow down heat buildup on sunny days. A lot of snow while we were gone. The heat-thaw cycles formed an ice dam at the edge. Water trickled down the doorframe and refroze leaving 2" of ice at the doorway. After a lot of chipping, that ice is clear but the door is still frozen shut. May take a hot air blow dryer to the door frame when this snow storm abates. Other than a hammer, any other good ideas out there?