How are drafts different from convection?
– Sometimes properly installed windows seem drafty for other reasons. Convection is a process that can make it seem as though your windows are drafty. Convection occurs when air gives up its heat to the cooler window glass and then sinks toward the floor. This process sucks warmer air toward the glass pane that is cooled upon reaching the window. The result is a drafty feeling. But the different densities of warmer and cooler air are actually causing this process, not some problem with the window’s performance. In a heated home, warm air circulates throughout, forcing some of the cold air around a window surface off of the glass. Convection is actually good news: it proves that new replacement windows are energy efficient, because that warm air is not escaping but merely “bouncing” off the window surface.
