Determining whether your front door needs maintenance or replacement, especially with a focus on energy-saving features, involves assessing its condition, performance, and energy efficiency. Check for drafts or air leaks around the edges of the door, as well as gaps between the door and the frame. Weatherstripping and caulking may need replacement to improve insulation and reduce energy loss. Generally speaking, exterior front door is a crucial part of keeping your home energy efficient, so if I were you, I wouldn't postpone its replacement.