A simple rule is to check window and door seals once a year, ideally before extreme seasons – just before winter in cold regions, or before peak summer where air conditioning is common. Over time, rubber gaskets harden, gaps appear, and frames shift slightly. Tiny openings may not look dramatic, but they quietly leak heated or cooled air.
The check doesn’t need fancy tools. On a windy day, run your hand slowly around the edges and feel for drafts. At night, you can also use a flashlight from one side while someone looks from the other to see if light sneaks through where it shouldn’t. For doors, see if you can slide a piece of paper between the frame and the door when it’s shut.
Catching these leaks early means you can fix them cheaply – with new weatherstripping, sealant, or small adjustments. If you ignore them for years, you end up paying more in energy bills and may eventually need bigger frame repairs. A quick yearly check is a small investment for a more comfortable and efficient home.