Leveling the door: Before commencing the spring winding, to check that you have the door properly leveled on the cables, considering all the factors above that make this a tricky adjustment, apply the winding cone setscrew lightly to lock the (unwound) spring cone temporarily on the torsion shaft, and momentarily lift the door slightly off the floor. Adjust the drum set as needed to level the door, repeating this slight lift test. Loosen the cone setscrew before winding the spring(s).
Insulation increases the efficiency of your door and can lower your electric will. You need R-value garage doors. These type of doors keep out hot and cold air and also provide a sound barrier between the outside and your garage. Insulated doors use polyurethane or polystyrene foam as insulation inside the door. More information about garage door replacement cost.