Loosen the set screws while holding each spring with a winding bar. Position a sturdy ladder to the side of the springs, rather than working directly in front of them, for safety reasons. Put on eye protection and leather gloves. Push a winding bar into the bottom hole of the winding cone on the outside of 1 spring. Use a wrench to loosen the 2 set screws. Keep a firm grip on the bar as the the spring will expand powerfully as the screws are released. Repeat on the other side.
A standard double garage door is 7 ft. high by 16 ft. wide. Standard single doors are 7 ft. high by 8 or 9 ft. wide. Because the doors are so large, few home centers and only some garage door stores keep many doors in stock, so expect to order one instead of buying it off the shelf. Garage doors are available in wood, fiberglass and steel. Steel doors, like ours, are light, maintenance-free, affordable, readily available, and have an insulating value as high as R-19.