Hinges position the door to properly compress the weatherstrip to help form a tight, even seal against air and moisture infiltration when the door closes. Spring-loaded hinges are used to create a self-closing door. Some areas require a fire door between a garage and a living area to be self-closing.
In this video, Therma-Tru provides a simple how-to tutorial on adjusting the tension of a spring-loaded hinge. It is important that the tension is properly set to maximize the lifespan of the spring within the hinge.