If the living room goes cold again by mid-evening even with the heating on, it isn’t the windows: it’s what’s still wide open above the hearth
That mysterious chill in your living room isn’t caused by poor windows—it’s your fireplace silently draining warm air away. An open chimney can account for up to 50% of your home’s heat loss, costing hundreds annually, yet most people never suspect the hearth is the real culprit.